Merge tag 'linux-can-next-for-6.9-20240213' of...

Merge tag 'linux-can-next-for-6.9-20240213' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
linux-can-next-for-6.9-20240213

this is a pull request of 23 patches for net-next/master.

The first patch is by Nicolas Maier and targets the CAN Broadcast
Manager (bcm), it adds message flags to distinguish between own local
and remote traffic.

Oliver Hartkopp contributes a patch for the CAN ISOTP protocol that
adds dynamic flow control parameters.

Stefan Mätje's patch series add support for the esd PCIe/402 CAN
interface family.

Markus Schneider-Pargmann contributes 14 patches for the m_can to
optimize for the SPI attached tcan4x5x controller.

A patch by Vincent Mailhol replaces Wolfgang Grandegger by Vincent
Mailhol as the CAN drivers Co-Maintainer.

Jimmy Assarsson's patch add support for the Kvaser M.2 PCIe 4xCAN
adapter.

A patch by Daniil Dulov removed a redundant NULL check in the softing
driver.

Oliver Hartkopp contributes a patch to add CANXL virtual CAN network
identifier support.

A patch by myself removes Naga Sureshkumar Relli as the maintainer of
the xilinx_can driver, as their email bounces.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/can.rst

@@ -444,6 +444,24 @@ definitions are specified for CAN specific MTUs in include/linux/can.h:
   #define CANFD_MTU (sizeof(struct canfd_frame)) == 72  => CAN FD frame
 
 
+Returned Message Flags
+----------------------
+
+When using the system call recvmsg(2) on a RAW or a BCM socket, the
+msg->msg_flags field may contain the following flags:
+
+MSG_DONTROUTE:
+	set when the received frame was created on the local host.
+
+MSG_CONFIRM:
+	set when the frame was sent via the socket it is received on.
+	This flag can be interpreted as a 'transmission confirmation' when the
+	CAN driver supports the echo of frames on driver level, see
+	:ref:`socketcan-local-loopback1` and :ref:`socketcan-local-loopback2`.
+	(Note: In order to receive such messages on a RAW socket,
+	CAN_RAW_RECV_OWN_MSGS must be set.)
+
+
 .. _socketcan-raw-sockets:
 
 RAW Protocol Sockets with can_filters (SOCK_RAW)
@@ -693,22 +711,6 @@ where the CAN_INV_FILTER flag is set in order to notch single CAN IDs or
 CAN ID ranges from the incoming traffic.
 
 
-RAW Socket Returned Message Flags
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-When using recvmsg() call, the msg->msg_flags may contain following flags:
-
-MSG_DONTROUTE:
-	set when the received frame was created on the local host.
-
-MSG_CONFIRM:
-	set when the frame was sent via the socket it is received on.
-	This flag can be interpreted as a 'transmission confirmation' when the
-	CAN driver supports the echo of frames on driver level, see
-	:ref:`socketcan-local-loopback1` and :ref:`socketcan-local-loopback2`.
-	In order to receive such messages, CAN_RAW_RECV_OWN_MSGS must be set.
-
-
 Broadcast Manager Protocol Sockets (SOCK_DGRAM)
 -----------------------------------------------
 

MAINTAINERS

@@ -4632,8 +4632,8 @@ S:	Maintained
 F:	net/sched/sch_cake.c
 
 CAN NETWORK DRIVERS
-M:	Wolfgang Grandegger <wg@grandegger.com>
 M:	Marc Kleine-Budde <mkl@pengutronix.de>
+M:	Vincent Mailhol <mailhol.vincent@wanadoo.fr>
 L:	linux-can@vger.kernel.org
 S:	Maintained
 W:	https://github.com/linux-can
@@ -7887,6 +7887,13 @@ S:	Maintained
 F:	include/linux/errseq.h
 F:	lib/errseq.c
 
+ESD CAN NETWORK DRIVERS
+M:	Stefan Mätje <stefan.maetje@esd.eu>
+R:	socketcan@esd.eu
+L:	linux-can@vger.kernel.org
+S:	Maintained
+F:	drivers/net/can/esd/
+
 ESD CAN/USB DRIVERS
 M:	Frank Jungclaus <frank.jungclaus@esd.eu>
 R:	socketcan@esd.eu
@@ -24142,7 +24149,6 @@ F:	drivers/net/ethernet/xilinx/xilinx_axienet*
 
 XILINX CAN DRIVER
 M:	Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
-R:	Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
 L:	linux-can@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/net/can/xilinx,can.yaml

drivers/net/can/Kconfig

@@ -168,6 +168,7 @@ config CAN_KVASER_PCIEFD
 	    Kvaser Mini PCI Express 2xHS v2
 	    Kvaser Mini PCI Express 1xCAN v3
 	    Kvaser Mini PCI Express 2xCAN v3
+	    Kvaser M.2 PCIe 4xCAN
 
 config CAN_SLCAN
 	tristate "Serial / USB serial CAN Adaptors (slcan)"
@@ -218,6 +219,7 @@ config CAN_XILINXCAN
 source "drivers/net/can/c_can/Kconfig"
 source "drivers/net/can/cc770/Kconfig"
 source "drivers/net/can/ctucanfd/Kconfig"
+source "drivers/net/can/esd/Kconfig"
 source "drivers/net/can/ifi_canfd/Kconfig"
 source "drivers/net/can/m_can/Kconfig"
 source "drivers/net/can/mscan/Kconfig"

drivers/net/can/Makefile

@@ -8,6 +8,7 @@ obj-$(CONFIG_CAN_VXCAN)		+= vxcan.o
 obj-$(CONFIG_CAN_SLCAN)		+= slcan/
 
 obj-y				+= dev/
+obj-y				+= esd/
 obj-y				+= rcar/
 obj-y				+= spi/
 obj-y				+= usb/

drivers/net/can/esd/Kconfig

+# SPDX-License-Identifier: GPL-2.0-only
+config CAN_ESD_402_PCI
+	tristate "esd electronics gmbh CAN-PCI(e)/402 family"
+	depends on PCI && HAS_DMA
+	help
+	  Support for C402 card family from esd electronics gmbh.
+	  This card family is based on the ESDACC CAN controller and
+	  available in several form factors:  PCI, PCIe, PCIe Mini,
+	  M.2 PCIe, CPCIserial, PMC, XMC  (see https://esd.eu/en)
+
+	  This driver can also be built as a module. In this case the
+	  module will be called esd_402_pci.

drivers/net/can/esd/Makefile

+# SPDX-License-Identifier: GPL-2.0-only
+#
+#  Makefile for esd gmbh ESDACC controller driver
+#
+esd_402_pci-objs := esdacc.o esd_402_pci-core.o
+
+obj-$(CONFIG_CAN_ESD_402_PCI) += esd_402_pci.o

drivers/net/can/esd/esd_402_pci-core.c

+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2015 - 2016 Thomas Körper, esd electronic system design gmbh
+ * Copyright (C) 2017 - 2023 Stefan Mätje, esd electronics gmbh
+ */
+
+#include <linux/can/dev.h>
+#include <linux/can.h>
+#include <linux/can/netlink.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/ethtool.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/pci.h>
+
+#include "esdacc.h"
+
+#define ESD_PCI_DEVICE_ID_PCIE402 0x0402
+
+#define PCI402_FPGA_VER_MIN 0x003d
+#define PCI402_MAX_CORES 6
+#define PCI402_BAR 0
+#define PCI402_IO_OV_OFFS 0
+#define PCI402_IO_PCIEP_OFFS 0x10000
+#define PCI402_IO_LEN_TOTAL 0x20000
+#define PCI402_IO_LEN_CORE 0x2000
+#define PCI402_PCICFG_MSICAP 0x50
+
+#define PCI402_DMA_MASK DMA_BIT_MASK(32)
+#define PCI402_DMA_SIZE ALIGN(0x10000, PAGE_SIZE)
+
+#define PCI402_PCIEP_OF_INT_ENABLE 0x0050
+#define PCI402_PCIEP_OF_BM_ADDR_LO 0x1000
+#define PCI402_PCIEP_OF_BM_ADDR_HI 0x1004
+#define PCI402_PCIEP_OF_MSI_ADDR_LO 0x1008
+#define PCI402_PCIEP_OF_MSI_ADDR_HI 0x100c
+
+struct pci402_card {
+	/* Actually mapped io space, all other iomem derived from this */
+	void __iomem *addr;
+	void __iomem *addr_pciep;
+
+	void *dma_buf;
+	dma_addr_t dma_hnd;
+
+	struct acc_ov ov;
+	struct acc_core *cores;
+
+	bool msi_enabled;
+};
+
+/* The BTR register capabilities described by the can_bittiming_const structures
+ * below are valid since esdACC version 0x0032.
+ */
+
+/* Used if the esdACC FPGA is built as CAN-Classic version. */
+static const struct can_bittiming_const pci402_bittiming_const = {
+	.name = "esd_402",
+	.tseg1_min = 1,
+	.tseg1_max = 16,
+	.tseg2_min = 1,
+	.tseg2_max = 8,
+	.sjw_max = 4,
+	.brp_min = 1,
+	.brp_max = 512,
+	.brp_inc = 1,
+};
+
+/* Used if the esdACC FPGA is built as CAN-FD version. */
+static const struct can_bittiming_const pci402_bittiming_const_canfd = {
+	.name = "esd_402fd",
+	.tseg1_min = 1,
+	.tseg1_max = 256,
+	.tseg2_min = 1,
+	.tseg2_max = 128,
+	.sjw_max = 128,
+	.brp_min = 1,
+	.brp_max = 256,
+	.brp_inc = 1,
+};
+
+static const struct net_device_ops pci402_acc_netdev_ops = {
+	.ndo_open = acc_open,
+	.ndo_stop = acc_close,
+	.ndo_start_xmit = acc_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
+	.ndo_eth_ioctl = can_eth_ioctl_hwts,
+};
+
+static const struct ethtool_ops pci402_acc_ethtool_ops = {
+	.get_ts_info = can_ethtool_op_get_ts_info_hwts,
+};
+
+static irqreturn_t pci402_interrupt(int irq, void *dev_id)
+{
+	struct pci_dev *pdev = dev_id;
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	irqreturn_t irq_status;
+
+	irq_status = acc_card_interrupt(&card->ov, card->cores);
+
+	return irq_status;
+}
+
+static int pci402_set_msiconfig(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	u32 addr_lo_offs = 0;
+	u32 addr_lo = 0;
+	u32 addr_hi = 0;
+	u32 data = 0;
+	u16 csr = 0;
+	int err;
+
+	/* The FPGA hard IP PCIe core implements a 64-bit MSI Capability
+	 * Register Format
+	 */
+	err = pci_read_config_word(pdev, PCI402_PCICFG_MSICAP + PCI_MSI_FLAGS, &csr);
+	if (err)
+		goto failed;
+
+	err = pci_read_config_dword(pdev, PCI402_PCICFG_MSICAP + PCI_MSI_ADDRESS_LO,
+				    &addr_lo);
+	if (err)
+		goto failed;
+	err = pci_read_config_dword(pdev, PCI402_PCICFG_MSICAP + PCI_MSI_ADDRESS_HI,
+				    &addr_hi);
+	if (err)
+		goto failed;
+
+	err = pci_read_config_dword(pdev, PCI402_PCICFG_MSICAP + PCI_MSI_DATA_64,
+				    &data);
+	if (err)
+		goto failed;
+
+	addr_lo_offs = addr_lo & 0x0000ffff;
+	addr_lo &= 0xffff0000;
+
+	if (addr_hi)
+		addr_lo |= 1; /* To enable 64-Bit addressing in PCIe endpoint */
+
+	if (!(csr & PCI_MSI_FLAGS_ENABLE)) {
+		err = -EINVAL;
+		goto failed;
+	}
+
+	iowrite32(addr_lo, card->addr_pciep + PCI402_PCIEP_OF_MSI_ADDR_LO);
+	iowrite32(addr_hi, card->addr_pciep + PCI402_PCIEP_OF_MSI_ADDR_HI);
+	acc_ov_write32(&card->ov, ACC_OV_OF_MSI_ADDRESSOFFSET, addr_lo_offs);
+	acc_ov_write32(&card->ov, ACC_OV_OF_MSI_DATA, data);
+
+	return 0;
+
+failed:
+	pci_warn(pdev, "Error while setting MSI configuration:\n"
+		 "CSR: 0x%.4x, addr: 0x%.8x%.8x, offs: 0x%.4x, data: 0x%.8x\n",
+		 csr, addr_hi, addr_lo, addr_lo_offs, data);
+
+	return err;
+}
+
+static int pci402_init_card(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+
+	card->ov.addr = card->addr + PCI402_IO_OV_OFFS;
+	card->addr_pciep = card->addr + PCI402_IO_PCIEP_OFFS;
+
+	acc_reset_fpga(&card->ov);
+	acc_init_ov(&card->ov, &pdev->dev);
+
+	if (card->ov.version < PCI402_FPGA_VER_MIN) {
+		pci_err(pdev,
+			"esdACC version (0x%.4x) outdated, please update\n",
+			card->ov.version);
+		return -EINVAL;
+	}
+
+	if (card->ov.timestamp_frequency != ACC_TS_FREQ_80MHZ) {
+		pci_err(pdev,
+			"esdACC timestamp frequency of %uHz not supported by driver. Aborted.\n",
+			card->ov.timestamp_frequency);
+		return -EINVAL;
+	}
+
+	if (card->ov.active_cores > PCI402_MAX_CORES) {
+		pci_err(pdev,
+			"Card with %u active cores not supported by driver. Aborted.\n",
+			card->ov.active_cores);
+		return -EINVAL;
+	}
+	card->cores = devm_kcalloc(&pdev->dev, card->ov.active_cores,
+				   sizeof(struct acc_core), GFP_KERNEL);
+	if (!card->cores)
+		return -ENOMEM;
+
+	if (card->ov.features & ACC_OV_REG_FEAT_MASK_CANFD) {
+		pci_warn(pdev,
+			 "esdACC with CAN-FD feature detected. This driver doesn't support CAN-FD yet.\n");
+	}
+
+#ifdef __LITTLE_ENDIAN
+	/* So card converts all busmastered data to LE for us: */
+	acc_ov_set_bits(&card->ov, ACC_OV_OF_MODE,
+			ACC_OV_REG_MODE_MASK_ENDIAN_LITTLE);
+#endif
+
+	return 0;
+}
+
+static int pci402_init_interrupt(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int err;
+
+	err = pci_enable_msi(pdev);
+	if (!err) {
+		err = pci402_set_msiconfig(pdev);
+		if (!err) {
+			card->msi_enabled = true;
+			acc_ov_set_bits(&card->ov, ACC_OV_OF_MODE,
+					ACC_OV_REG_MODE_MASK_MSI_ENABLE);
+			pci_dbg(pdev, "MSI preparation done\n");
+		}
+	}
+
+	err = devm_request_irq(&pdev->dev, pdev->irq, pci402_interrupt,
+			       IRQF_SHARED, dev_name(&pdev->dev), pdev);
+	if (err)
+		goto failure_msidis;
+
+	iowrite32(1, card->addr_pciep + PCI402_PCIEP_OF_INT_ENABLE);
+
+	return 0;
+
+failure_msidis:
+	if (card->msi_enabled) {
+		acc_ov_clear_bits(&card->ov, ACC_OV_OF_MODE,
+				  ACC_OV_REG_MODE_MASK_MSI_ENABLE);
+		pci_disable_msi(pdev);
+		card->msi_enabled = false;
+	}
+
+	return err;
+}
+
+static void pci402_finish_interrupt(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+
+	iowrite32(0, card->addr_pciep + PCI402_PCIEP_OF_INT_ENABLE);
+	devm_free_irq(&pdev->dev, pdev->irq, pdev);
+
+	if (card->msi_enabled) {
+		acc_ov_clear_bits(&card->ov, ACC_OV_OF_MODE,
+				  ACC_OV_REG_MODE_MASK_MSI_ENABLE);
+		pci_disable_msi(pdev);
+		card->msi_enabled = false;
+	}
+}
+
+static int pci402_init_dma(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int err;
+
+	err = dma_set_coherent_mask(&pdev->dev, PCI402_DMA_MASK);
+	if (err) {
+		pci_err(pdev, "DMA set mask failed!\n");
+		return err;
+	}
+
+	/* The esdACC DMA engine needs the DMA buffer aligned to a 64k
+	 * boundary. The DMA API guarantees to align the returned buffer to the
+	 * smallest PAGE_SIZE order which is greater than or equal to the
+	 * requested size. With PCI402_DMA_SIZE == 64kB this suffices here.
+	 */
+	card->dma_buf = dma_alloc_coherent(&pdev->dev, PCI402_DMA_SIZE,
+					   &card->dma_hnd, GFP_KERNEL);
+	if (!card->dma_buf)
+		return -ENOMEM;
+
+	acc_init_bm_ptr(&card->ov, card->cores, card->dma_buf);
+
+	iowrite32(card->dma_hnd,
+		  card->addr_pciep + PCI402_PCIEP_OF_BM_ADDR_LO);
+	iowrite32(0, card->addr_pciep + PCI402_PCIEP_OF_BM_ADDR_HI);
+
+	pci_set_master(pdev);
+
+	acc_ov_set_bits(&card->ov, ACC_OV_OF_MODE,
+			ACC_OV_REG_MODE_MASK_BM_ENABLE);
+
+	return 0;
+}
+
+static void pci402_finish_dma(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int i;
+
+	acc_ov_clear_bits(&card->ov, ACC_OV_OF_MODE,
+			  ACC_OV_REG_MODE_MASK_BM_ENABLE);
+
+	pci_clear_master(pdev);
+
+	iowrite32(0, card->addr_pciep + PCI402_PCIEP_OF_BM_ADDR_LO);
+	iowrite32(0, card->addr_pciep + PCI402_PCIEP_OF_BM_ADDR_HI);
+
+	card->ov.bmfifo.messages = NULL;
+	card->ov.bmfifo.irq_cnt = NULL;
+	for (i = 0; i < card->ov.active_cores; i++) {
+		struct acc_core *core = &card->cores[i];
+
+		core->bmfifo.messages = NULL;
+		core->bmfifo.irq_cnt = NULL;
+	}
+
+	dma_free_coherent(&pdev->dev, PCI402_DMA_SIZE, card->dma_buf,
+			  card->dma_hnd);
+	card->dma_buf = NULL;
+}
+
+static void pci402_unregister_core(struct acc_core *core)
+{
+	netdev_info(core->netdev, "unregister\n");
+	unregister_candev(core->netdev);
+
+	free_candev(core->netdev);
+	core->netdev = NULL;
+}
+
+static int pci402_init_cores(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int err;
+	int i;
+
+	for (i = 0; i < card->ov.active_cores; i++) {
+		struct acc_core *core = &card->cores[i];
+		struct acc_net_priv *priv;
+		struct net_device *netdev;
+		u32 fifo_config;
+
+		core->addr = card->ov.addr + (i + 1) * PCI402_IO_LEN_CORE;
+
+		fifo_config = acc_read32(core, ACC_CORE_OF_TXFIFO_CONFIG);
+		core->tx_fifo_size = (fifo_config >> 24);
+		if (core->tx_fifo_size <= 1) {
+			pci_err(pdev, "Invalid tx_fifo_size!\n");
+			err = -EINVAL;
+			goto failure;
+		}
+
+		netdev = alloc_candev(sizeof(*priv), core->tx_fifo_size);
+		if (!netdev) {
+			err = -ENOMEM;
+			goto failure;
+		}
+		core->netdev = netdev;
+
+		netdev->flags |= IFF_ECHO;
+		netdev->dev_port = i;
+		netdev->netdev_ops = &pci402_acc_netdev_ops;
+		netdev->ethtool_ops = &pci402_acc_ethtool_ops;
+		SET_NETDEV_DEV(netdev, &pdev->dev);
+
+		priv = netdev_priv(netdev);
+		priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
+			CAN_CTRLMODE_LISTENONLY |
+			CAN_CTRLMODE_BERR_REPORTING |
+			CAN_CTRLMODE_CC_LEN8_DLC;
+
+		priv->can.clock.freq = card->ov.core_frequency;
+		if (card->ov.features & ACC_OV_REG_FEAT_MASK_CANFD)
+			priv->can.bittiming_const = &pci402_bittiming_const_canfd;
+		else
+			priv->can.bittiming_const = &pci402_bittiming_const;
+		priv->can.do_set_bittiming = acc_set_bittiming;
+		priv->can.do_set_mode = acc_set_mode;
+		priv->can.do_get_berr_counter = acc_get_berr_counter;
+
+		priv->core = core;
+		priv->ov = &card->ov;
+
+		err = register_candev(netdev);
+		if (err) {
+			free_candev(core->netdev);
+			core->netdev = NULL;
+			goto failure;
+		}
+
+		netdev_info(netdev, "registered\n");
+	}
+
+	return 0;
+
+failure:
+	for (i--; i >= 0; i--)
+		pci402_unregister_core(&card->cores[i]);
+
+	return err;
+}
+
+static void pci402_finish_cores(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < card->ov.active_cores; i++)
+		pci402_unregister_core(&card->cores[i]);
+}
+
+static int pci402_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	struct pci402_card *card = NULL;
+	int err;
+
+	err = pci_enable_device(pdev);
+	if (err)
+		return err;
+
+	card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
+	if (!card) {
+		err = -ENOMEM;
+		goto failure_disable_pci;
+	}
+
+	pci_set_drvdata(pdev, card);
+
+	err = pci_request_regions(pdev, pci_name(pdev));
+	if (err)
+		goto failure_disable_pci;
+
+	card->addr = pci_iomap(pdev, PCI402_BAR, PCI402_IO_LEN_TOTAL);
+	if (!card->addr) {
+		err = -ENOMEM;
+		goto failure_release_regions;
+	}
+
+	err = pci402_init_card(pdev);
+	if (err)
+		goto failure_unmap;
+
+	err = pci402_init_dma(pdev);
+	if (err)
+		goto failure_unmap;
+
+	err = pci402_init_interrupt(pdev);
+	if (err)
+		goto failure_finish_dma;
+
+	err = pci402_init_cores(pdev);
+	if (err)
+		goto failure_finish_interrupt;
+
+	return 0;
+
+failure_finish_interrupt:
+	pci402_finish_interrupt(pdev);
+
+failure_finish_dma:
+	pci402_finish_dma(pdev);
+
+failure_unmap:
+	pci_iounmap(pdev, card->addr);
+
+failure_release_regions:
+	pci_release_regions(pdev);
+
+failure_disable_pci:
+	pci_disable_device(pdev);
+
+	return err;
+}
+
+static void pci402_remove(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+
+	pci402_finish_interrupt(pdev);
+	pci402_finish_cores(pdev);
+	pci402_finish_dma(pdev);
+	pci_iounmap(pdev, card->addr);
+	pci_release_regions(pdev);
+	pci_disable_device(pdev);
+}
+
+static const struct pci_device_id pci402_tbl[] = {
+	{
+		.vendor = PCI_VENDOR_ID_ESDGMBH,
+		.device = ESD_PCI_DEVICE_ID_PCIE402,
+		.subvendor = PCI_VENDOR_ID_ESDGMBH,
+		.subdevice = PCI_ANY_ID,
+	},
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, pci402_tbl);
+
+static struct pci_driver pci402_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = pci402_tbl,
+	.probe = pci402_probe,
+	.remove = pci402_remove,
+};
+module_pci_driver(pci402_driver);
+
+MODULE_DESCRIPTION("Socket-CAN driver for esd CAN 402 card family with esdACC core on PCIe");
+MODULE_AUTHOR("Thomas Körper <socketcan@esd.eu>");
+MODULE_AUTHOR("Stefan Mätje <stefan.maetje@esd.eu>");
+MODULE_LICENSE("GPL");

drivers/net/can/esd/esdacc.c

+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2015 - 2016 Thomas Körper, esd electronic system design gmbh
+ * Copyright (C) 2017 - 2023 Stefan Mätje, esd electronics gmbh
+ */
+
+#include "esdacc.h"
+
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/ktime.h>
+
+/* esdACC ID register layout */
+#define ACC_ID_ID_MASK GENMASK(28, 0)
+#define ACC_ID_EFF_FLAG BIT(29)
+
+/* esdACC DLC register layout */
+#define ACC_DLC_DLC_MASK GENMASK(3, 0)
+#define ACC_DLC_RTR_FLAG BIT(4)
+#define ACC_DLC_TXD_FLAG BIT(5)
+
+/* ecc value of esdACC equals SJA1000's ECC register */
+#define ACC_ECC_SEG 0x1f
+#define ACC_ECC_DIR 0x20
+#define ACC_ECC_BIT 0x00
+#define ACC_ECC_FORM 0x40
+#define ACC_ECC_STUFF 0x80
+#define ACC_ECC_MASK 0xc0
+
+/* esdACC Status Register bits. Unused bits not documented. */
+#define ACC_REG_STATUS_MASK_STATUS_ES BIT(17)
+#define ACC_REG_STATUS_MASK_STATUS_EP BIT(18)
+#define ACC_REG_STATUS_MASK_STATUS_BS BIT(19)
+
+/* esdACC Overview Module BM_IRQ_Mask register related defines */
+/*   Two bit wide command masks to mask or unmask a single core IRQ */
+#define ACC_BM_IRQ_UNMASK BIT(0)
+#define ACC_BM_IRQ_MASK (ACC_BM_IRQ_UNMASK << 1)
+/*   Command to unmask all IRQ sources. Created by shifting
+ *   and oring the two bit wide ACC_BM_IRQ_UNMASK 16 times.
+ */
+#define ACC_BM_IRQ_UNMASK_ALL 0x55555555U
+
+static void acc_resetmode_enter(struct acc_core *core)
+{
+	acc_set_bits(core, ACC_CORE_OF_CTRL_MODE,
+		     ACC_REG_CONTROL_MASK_MODE_RESETMODE);
+
+	/* Read back reset mode bit to flush PCI write posting */
+	acc_resetmode_entered(core);
+}
+
+static void acc_resetmode_leave(struct acc_core *core)
+{
+	acc_clear_bits(core, ACC_CORE_OF_CTRL_MODE,
+		       ACC_REG_CONTROL_MASK_MODE_RESETMODE);
+
+	/* Read back reset mode bit to flush PCI write posting */
+	acc_resetmode_entered(core);
+}
+
+static void acc_txq_put(struct acc_core *core, u32 acc_id, u8 acc_dlc,
+			const void *data)
+{
+	acc_write32_noswap(core, ACC_CORE_OF_TXFIFO_DATA_1,
+			   *((const u32 *)(data + 4)));
+	acc_write32_noswap(core, ACC_CORE_OF_TXFIFO_DATA_0,
+			   *((const u32 *)data));
+	acc_write32(core, ACC_CORE_OF_TXFIFO_DLC, acc_dlc);
+	/* CAN id must be written at last. This write starts TX. */
+	acc_write32(core, ACC_CORE_OF_TXFIFO_ID, acc_id);
+}
+
+static u8 acc_tx_fifo_next(struct acc_core *core, u8 tx_fifo_idx)
+{
+	++tx_fifo_idx;
+	if (tx_fifo_idx >= core->tx_fifo_size)
+		tx_fifo_idx = 0U;
+	return tx_fifo_idx;
+}
+
+/* Convert timestamp from esdACC time stamp ticks to ns
+ *
+ * The conversion factor ts2ns from time stamp counts to ns is basically
+ *	ts2ns = NSEC_PER_SEC / timestamp_frequency
+ *
+ * We handle here only a fixed timestamp frequency of 80MHz. The
+ * resulting ts2ns factor would be 12.5.
+ *
+ * At the end we multiply by 12 and add the half of the HW timestamp
+ * to get a multiplication by 12.5. This way any overflow is
+ * avoided until ktime_t itself overflows.
+ */
+#define ACC_TS_FACTOR (NSEC_PER_SEC / ACC_TS_FREQ_80MHZ)
+#define ACC_TS_80MHZ_SHIFT 1
+
+static ktime_t acc_ts2ktime(struct acc_ov *ov, u64 ts)
+{
+	u64 ns;
+
+	ns = (ts * ACC_TS_FACTOR) + (ts >> ACC_TS_80MHZ_SHIFT);
+
+	return ns_to_ktime(ns);
+}
+
+#undef ACC_TS_FACTOR
+#undef ACC_TS_80MHZ_SHIFT
+
+void acc_init_ov(struct acc_ov *ov, struct device *dev)
+{
+	u32 temp;
+
+	temp = acc_ov_read32(ov, ACC_OV_OF_VERSION);
+	ov->version = temp;
+	ov->features = (temp >> 16);
+
+	temp = acc_ov_read32(ov, ACC_OV_OF_INFO);
+	ov->total_cores = temp;
+	ov->active_cores = (temp >> 8);
+
+	ov->core_frequency = acc_ov_read32(ov, ACC_OV_OF_CANCORE_FREQ);
+	ov->timestamp_frequency = acc_ov_read32(ov, ACC_OV_OF_TS_FREQ_LO);
+
+	/* Depending on esdACC feature NEW_PSC enable the new prescaler
+	 * or adjust core_frequency according to the implicit division by 2.
+	 */
+	if (ov->features & ACC_OV_REG_FEAT_MASK_NEW_PSC) {
+		acc_ov_set_bits(ov, ACC_OV_OF_MODE,
+				ACC_OV_REG_MODE_MASK_NEW_PSC_ENABLE);
+	} else {
+		ov->core_frequency /= 2;
+	}
+
+	dev_dbg(dev,
+		"esdACC v%u, freq: %u/%u, feat/strap: 0x%x/0x%x, cores: %u/%u\n",
+		ov->version, ov->core_frequency, ov->timestamp_frequency,
+		ov->features, acc_ov_read32(ov, ACC_OV_OF_INFO) >> 16,
+		ov->active_cores, ov->total_cores);
+}
+
+void acc_init_bm_ptr(struct acc_ov *ov, struct acc_core *cores, const void *mem)
+{
+	unsigned int u;
+
+	/* DMA buffer layout as follows where N is the number of CAN cores
+	 * implemented in the FPGA, i.e. N = ov->total_cores
+	 *
+	 *  Section Layout           Section size
+	 * ----------------------------------------------
+	 *  FIFO Card/Overview	     ACC_CORE_DMABUF_SIZE
+	 *  FIFO Core0               ACC_CORE_DMABUF_SIZE
+	 *  ...                      ...
+	 *  FIFO CoreN               ACC_CORE_DMABUF_SIZE
+	 *  irq_cnt Card/Overview    sizeof(u32)
+	 *  irq_cnt Core0            sizeof(u32)
+	 *  ...                      ...
+	 *  irq_cnt CoreN            sizeof(u32)
+	 */
+	ov->bmfifo.messages = mem;
+	ov->bmfifo.irq_cnt = mem + (ov->total_cores + 1U) * ACC_CORE_DMABUF_SIZE;
+
+	for (u = 0U; u < ov->active_cores; u++) {
+		struct acc_core *core = &cores[u];
+
+		core->bmfifo.messages = mem + (u + 1U) * ACC_CORE_DMABUF_SIZE;
+		core->bmfifo.irq_cnt = ov->bmfifo.irq_cnt + (u + 1U);
+	}
+}
+
+int acc_open(struct net_device *netdev)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	struct acc_core *core = priv->core;
+	u32 tx_fifo_status;
+	u32 ctrl_mode;
+	int err;
+
+	/* Retry to enter RESET mode if out of sync. */
+	if (priv->can.state != CAN_STATE_STOPPED) {
+		netdev_warn(netdev, "Entered %s() with bad can.state: %s\n",
+			    __func__, can_get_state_str(priv->can.state));
+		acc_resetmode_enter(core);
+		priv->can.state = CAN_STATE_STOPPED;
+	}
+
+	err = open_candev(netdev);
+	if (err)
+		return err;
+
+	ctrl_mode = ACC_REG_CONTROL_MASK_IE_RXTX |
+			ACC_REG_CONTROL_MASK_IE_TXERROR |
+			ACC_REG_CONTROL_MASK_IE_ERRWARN |
+			ACC_REG_CONTROL_MASK_IE_OVERRUN |
+			ACC_REG_CONTROL_MASK_IE_ERRPASS;
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
+		ctrl_mode |= ACC_REG_CONTROL_MASK_IE_BUSERR;
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+		ctrl_mode |= ACC_REG_CONTROL_MASK_MODE_LOM;
+
+	acc_set_bits(core, ACC_CORE_OF_CTRL_MODE, ctrl_mode);
+
+	acc_resetmode_leave(core);
+	priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+	/* Resync TX FIFO indices to HW state after (re-)start. */
+	tx_fifo_status = acc_read32(core, ACC_CORE_OF_TXFIFO_STATUS);
+	core->tx_fifo_head = tx_fifo_status & 0xff;
+	core->tx_fifo_tail = (tx_fifo_status >> 8) & 0xff;
+
+	netif_start_queue(netdev);
+	return 0;
+}
+
+int acc_close(struct net_device *netdev)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	struct acc_core *core = priv->core;
+
+	acc_clear_bits(core, ACC_CORE_OF_CTRL_MODE,
+		       ACC_REG_CONTROL_MASK_IE_RXTX |
+		       ACC_REG_CONTROL_MASK_IE_TXERROR |
+		       ACC_REG_CONTROL_MASK_IE_ERRWARN |
+		       ACC_REG_CONTROL_MASK_IE_OVERRUN |
+		       ACC_REG_CONTROL_MASK_IE_ERRPASS |
+		       ACC_REG_CONTROL_MASK_IE_BUSERR);
+
+	netif_stop_queue(netdev);
+	acc_resetmode_enter(core);
+	priv->can.state = CAN_STATE_STOPPED;
+
+	/* Mark pending TX requests to be aborted after controller restart. */
+	acc_write32(core, ACC_CORE_OF_TX_ABORT_MASK, 0xffff);
+
+	/* ACC_REG_CONTROL_MASK_MODE_LOM is only accessible in RESET mode */
+	acc_clear_bits(core, ACC_CORE_OF_CTRL_MODE,
+		       ACC_REG_CONTROL_MASK_MODE_LOM);
+
+	close_candev(netdev);
+	return 0;
+}
+
+netdev_tx_t acc_start_xmit(struct sk_buff *skb, struct net_device *netdev)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	struct acc_core *core = priv->core;
+	struct can_frame *cf = (struct can_frame *)skb->data;
+	u8 tx_fifo_head = core->tx_fifo_head;
+	int fifo_usage;
+	u32 acc_id;
+	u8 acc_dlc;
+
+	if (can_dropped_invalid_skb(netdev, skb))
+		return NETDEV_TX_OK;
+
+	/* Access core->tx_fifo_tail only once because it may be changed
+	 * from the interrupt level.
+	 */
+	fifo_usage = tx_fifo_head - core->tx_fifo_tail;
+	if (fifo_usage < 0)
+		fifo_usage += core->tx_fifo_size;
+
+	if (fifo_usage >= core->tx_fifo_size - 1) {
+		netdev_err(core->netdev,
+			   "BUG: TX ring full when queue awake!\n");
+		netif_stop_queue(netdev);
+		return NETDEV_TX_BUSY;
+	}
+
+	if (fifo_usage == core->tx_fifo_size - 2)
+		netif_stop_queue(netdev);
+
+	acc_dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);
+	if (cf->can_id & CAN_RTR_FLAG)
+		acc_dlc |= ACC_DLC_RTR_FLAG;
+
+	if (cf->can_id & CAN_EFF_FLAG) {
+		acc_id = cf->can_id & CAN_EFF_MASK;
+		acc_id |= ACC_ID_EFF_FLAG;
+	} else {
+		acc_id = cf->can_id & CAN_SFF_MASK;
+	}
+
+	can_put_echo_skb(skb, netdev, core->tx_fifo_head, 0);
+
+	core->tx_fifo_head = acc_tx_fifo_next(core, tx_fifo_head);
+
+	acc_txq_put(core, acc_id, acc_dlc, cf->data);
+
+	return NETDEV_TX_OK;
+}
+
+int acc_get_berr_counter(const struct net_device *netdev,
+			 struct can_berr_counter *bec)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	u32 core_status = acc_read32(priv->core, ACC_CORE_OF_STATUS);
+
+	bec->txerr = (core_status >> 8) & 0xff;
+	bec->rxerr = core_status & 0xff;
+
+	return 0;
+}
+
+int acc_set_mode(struct net_device *netdev, enum can_mode mode)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+
+	switch (mode) {
+	case CAN_MODE_START:
+		/* Paranoid FIFO index check. */
+		{
+			const u32 tx_fifo_status =
+				acc_read32(priv->core, ACC_CORE_OF_TXFIFO_STATUS);
+			const u8 hw_fifo_head = tx_fifo_status;
+
+			if (hw_fifo_head != priv->core->tx_fifo_head ||
+			    hw_fifo_head != priv->core->tx_fifo_tail) {
+				netdev_warn(netdev,
+					    "TX FIFO mismatch: T %2u H %2u; TFHW %#08x\n",
+					    priv->core->tx_fifo_tail,
+					    priv->core->tx_fifo_head,
+					    tx_fifo_status);
+			}
+		}
+		acc_resetmode_leave(priv->core);
+		/* To leave the bus-off state the esdACC controller begins
+		 * here a grace period where it counts 128 "idle conditions" (each
+		 * of 11 consecutive recessive bits) on the bus as required
+		 * by the CAN spec.
+		 *
+		 * During this time the TX FIFO may still contain already
+		 * aborted "zombie" frames that are only drained from the FIFO
+		 * at the end of the grace period.
+		 *
+		 * To not to interfere with this drain process we don't
+		 * call netif_wake_queue() here. When the controller reaches
+		 * the error-active state again, it informs us about that
+		 * with an acc_bmmsg_errstatechange message. Then
+		 * netif_wake_queue() is called from
+		 * handle_core_msg_errstatechange() instead.
+		 */
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+int acc_set_bittiming(struct net_device *netdev)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	const struct can_bittiming *bt = &priv->can.bittiming;
+	u32 brp;
+	u32 btr;
+
+	if (priv->ov->features & ACC_OV_REG_FEAT_MASK_CANFD) {
+		u32 fbtr = 0;
+
+		netdev_dbg(netdev, "bit timing: brp %u, prop %u, ph1 %u ph2 %u, sjw %u\n",
+			   bt->brp, bt->prop_seg,
+			   bt->phase_seg1, bt->phase_seg2, bt->sjw);
+
+		brp = FIELD_PREP(ACC_REG_BRP_FD_MASK_BRP, bt->brp - 1);
+
+		btr = FIELD_PREP(ACC_REG_BTR_FD_MASK_TSEG1, bt->phase_seg1 + bt->prop_seg - 1);
+		btr |= FIELD_PREP(ACC_REG_BTR_FD_MASK_TSEG2, bt->phase_seg2 - 1);
+		btr |= FIELD_PREP(ACC_REG_BTR_FD_MASK_SJW, bt->sjw - 1);
+
+		/* Keep order of accesses to ACC_CORE_OF_BRP and ACC_CORE_OF_BTR. */
+		acc_write32(priv->core, ACC_CORE_OF_BRP, brp);
+		acc_write32(priv->core, ACC_CORE_OF_BTR, btr);
+
+		netdev_dbg(netdev, "esdACC: BRP %u, NBTR 0x%08x, DBTR 0x%08x",
+			   brp, btr, fbtr);
+	} else {
+		netdev_dbg(netdev, "bit timing: brp %u, prop %u, ph1 %u ph2 %u, sjw %u\n",
+			   bt->brp, bt->prop_seg,
+			   bt->phase_seg1, bt->phase_seg2, bt->sjw);
+
+		brp = FIELD_PREP(ACC_REG_BRP_CL_MASK_BRP, bt->brp - 1);
+
+		btr = FIELD_PREP(ACC_REG_BTR_CL_MASK_TSEG1, bt->phase_seg1 + bt->prop_seg - 1);
+		btr |= FIELD_PREP(ACC_REG_BTR_CL_MASK_TSEG2, bt->phase_seg2 - 1);
+		btr |= FIELD_PREP(ACC_REG_BTR_CL_MASK_SJW, bt->sjw - 1);
+
+		/* Keep order of accesses to ACC_CORE_OF_BRP and ACC_CORE_OF_BTR. */
+		acc_write32(priv->core, ACC_CORE_OF_BRP, brp);
+		acc_write32(priv->core, ACC_CORE_OF_BTR, btr);
+
+		netdev_dbg(netdev, "esdACC: BRP %u, BTR 0x%08x", brp, btr);
+	}
+
+	return 0;
+}
+
+static void handle_core_msg_rxtxdone(struct acc_core *core,
+				     const struct acc_bmmsg_rxtxdone *msg)
+{
+	struct acc_net_priv *priv = netdev_priv(core->netdev);
+	struct net_device_stats *stats = &core->netdev->stats;
+	struct sk_buff *skb;
+
+	if (msg->acc_dlc.len & ACC_DLC_TXD_FLAG) {
+		u8 tx_fifo_tail = core->tx_fifo_tail;
+
+		if (core->tx_fifo_head == tx_fifo_tail) {
+			netdev_warn(core->netdev,
+				    "TX interrupt, but queue is empty!?\n");
+			return;
+		}
+
+		/* Direct access echo skb to attach HW time stamp. */
+		skb = priv->can.echo_skb[tx_fifo_tail];
+		if (skb) {
+			skb_hwtstamps(skb)->hwtstamp =
+				acc_ts2ktime(priv->ov, msg->ts);
+		}
+
+		stats->tx_packets++;
+		stats->tx_bytes += can_get_echo_skb(core->netdev, tx_fifo_tail,
+						    NULL);
+
+		core->tx_fifo_tail = acc_tx_fifo_next(core, tx_fifo_tail);
+
+		netif_wake_queue(core->netdev);
+
+	} else {
+		struct can_frame *cf;
+
+		skb = alloc_can_skb(core->netdev, &cf);
+		if (!skb) {
+			stats->rx_dropped++;
+			return;
+		}
+
+		cf->can_id = msg->id & ACC_ID_ID_MASK;
+		if (msg->id & ACC_ID_EFF_FLAG)
+			cf->can_id |= CAN_EFF_FLAG;
+
+		can_frame_set_cc_len(cf, msg->acc_dlc.len & ACC_DLC_DLC_MASK,
+				     priv->can.ctrlmode);
+
+		if (msg->acc_dlc.len & ACC_DLC_RTR_FLAG) {
+			cf->can_id |= CAN_RTR_FLAG;
+		} else {
+			memcpy(cf->data, msg->data, cf->len);
+			stats->rx_bytes += cf->len;
+		}
+		stats->rx_packets++;
+
+		skb_hwtstamps(skb)->hwtstamp = acc_ts2ktime(priv->ov, msg->ts);
+
+		netif_rx(skb);
+	}
+}
+
+static void handle_core_msg_txabort(struct acc_core *core,
+				    const struct acc_bmmsg_txabort *msg)
+{
+	struct net_device_stats *stats = &core->netdev->stats;
+	u8 tx_fifo_tail = core->tx_fifo_tail;
+	u32 abort_mask = msg->abort_mask;   /* u32 extend to avoid warnings later */
+
+	/* The abort_mask shows which frames were aborted in esdACC's FIFO. */
+	while (tx_fifo_tail != core->tx_fifo_head && (abort_mask)) {
+		const u32 tail_mask = (1U << tx_fifo_tail);
+
+		if (!(abort_mask & tail_mask))
+			break;
+		abort_mask &= ~tail_mask;
+
+		can_free_echo_skb(core->netdev, tx_fifo_tail, NULL);
+		stats->tx_dropped++;
+		stats->tx_aborted_errors++;
+
+		tx_fifo_tail = acc_tx_fifo_next(core, tx_fifo_tail);
+	}
+	core->tx_fifo_tail = tx_fifo_tail;
+	if (abort_mask)
+		netdev_warn(core->netdev, "Unhandled aborted messages\n");
+
+	if (!acc_resetmode_entered(core))
+		netif_wake_queue(core->netdev);
+}
+
+static void handle_core_msg_overrun(struct acc_core *core,
+				    const struct acc_bmmsg_overrun *msg)
+{
+	struct acc_net_priv *priv = netdev_priv(core->netdev);
+	struct net_device_stats *stats = &core->netdev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+
+	/* lost_cnt may be 0 if not supported by esdACC version */
+	if (msg->lost_cnt) {
+		stats->rx_errors += msg->lost_cnt;
+		stats->rx_over_errors += msg->lost_cnt;
+	} else {
+		stats->rx_errors++;
+		stats->rx_over_errors++;
+	}
+
+	skb = alloc_can_err_skb(core->netdev, &cf);
+	if (!skb)
+		return;
+
+	cf->can_id |= CAN_ERR_CRTL;
+	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+
+	skb_hwtstamps(skb)->hwtstamp = acc_ts2ktime(priv->ov, msg->ts);
+
+	netif_rx(skb);
+}
+
+static void handle_core_msg_buserr(struct acc_core *core,
+				   const struct acc_bmmsg_buserr *msg)
+{
+	struct acc_net_priv *priv = netdev_priv(core->netdev);
+	struct net_device_stats *stats = &core->netdev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	const u32 reg_status = msg->reg_status;
+	const u8 rxerr = reg_status;
+	const u8 txerr = (reg_status >> 8);
+	u8 can_err_prot_type = 0U;
+
+	priv->can.can_stats.bus_error++;
+
+	/* Error occurred during transmission? */
+	if (msg->ecc & ACC_ECC_DIR) {
+		stats->rx_errors++;
+	} else {
+		can_err_prot_type |= CAN_ERR_PROT_TX;
+		stats->tx_errors++;
+	}
+	/* Determine error type */
+	switch (msg->ecc & ACC_ECC_MASK) {
+	case ACC_ECC_BIT:
+		can_err_prot_type |= CAN_ERR_PROT_BIT;
+		break;
+	case ACC_ECC_FORM:
+		can_err_prot_type |= CAN_ERR_PROT_FORM;
+		break;
+	case ACC_ECC_STUFF:
+		can_err_prot_type |= CAN_ERR_PROT_STUFF;
+		break;
+	default:
+		can_err_prot_type |= CAN_ERR_PROT_UNSPEC;
+		break;
+	}
+
+	skb = alloc_can_err_skb(core->netdev, &cf);
+	if (!skb)
+		return;
+
+	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR | CAN_ERR_CNT;
+
+	/* Set protocol error type */
+	cf->data[2] = can_err_prot_type;
+	/* Set error location */
+	cf->data[3] = msg->ecc & ACC_ECC_SEG;
+
+	/* Insert CAN TX and RX error counters. */
+	cf->data[6] = txerr;
+	cf->data[7] = rxerr;
+
+	skb_hwtstamps(skb)->hwtstamp = acc_ts2ktime(priv->ov, msg->ts);
+
+	netif_rx(skb);
+}
+
+static void
+handle_core_msg_errstatechange(struct acc_core *core,
+			       const struct acc_bmmsg_errstatechange *msg)
+{
+	struct acc_net_priv *priv = netdev_priv(core->netdev);
+	struct can_frame *cf = NULL;
+	struct sk_buff *skb;
+	const u32 reg_status = msg->reg_status;
+	const u8 rxerr = reg_status;
+	const u8 txerr = (reg_status >> 8);
+	enum can_state new_state;
+
+	if (reg_status & ACC_REG_STATUS_MASK_STATUS_BS) {
+		new_state = CAN_STATE_BUS_OFF;
+	} else if (reg_status & ACC_REG_STATUS_MASK_STATUS_EP) {
+		new_state = CAN_STATE_ERROR_PASSIVE;
+	} else if (reg_status & ACC_REG_STATUS_MASK_STATUS_ES) {
+		new_state = CAN_STATE_ERROR_WARNING;
+	} else {
+		new_state = CAN_STATE_ERROR_ACTIVE;
+		if (priv->can.state == CAN_STATE_BUS_OFF) {
+			/* See comment in acc_set_mode() for CAN_MODE_START */
+			netif_wake_queue(core->netdev);
+		}
+	}
+
+	skb = alloc_can_err_skb(core->netdev, &cf);
+
+	if (new_state != priv->can.state) {
+		enum can_state tx_state, rx_state;
+
+		tx_state = (txerr >= rxerr) ?
+			new_state : CAN_STATE_ERROR_ACTIVE;
+		rx_state = (rxerr >= txerr) ?
+			new_state : CAN_STATE_ERROR_ACTIVE;
+
+		/* Always call can_change_state() to update the state
+		 * even if alloc_can_err_skb() may have failed.
+		 * can_change_state() can cope with a NULL cf pointer.
+		 */
+		can_change_state(core->netdev, cf, tx_state, rx_state);
+	}
+
+	if (skb) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+
+		skb_hwtstamps(skb)->hwtstamp = acc_ts2ktime(priv->ov, msg->ts);
+
+		netif_rx(skb);
+	}
+
+	if (new_state == CAN_STATE_BUS_OFF) {
+		acc_write32(core, ACC_CORE_OF_TX_ABORT_MASK, 0xffff);
+		can_bus_off(core->netdev);
+	}
+}
+
+static void handle_core_interrupt(struct acc_core *core)
+{
+	u32 msg_fifo_head = core->bmfifo.local_irq_cnt & 0xff;
+
+	while (core->bmfifo.msg_fifo_tail != msg_fifo_head) {
+		const union acc_bmmsg *msg =
+			&core->bmfifo.messages[core->bmfifo.msg_fifo_tail];
+
+		switch (msg->msg_id) {
+		case BM_MSG_ID_RXTXDONE:
+			handle_core_msg_rxtxdone(core, &msg->rxtxdone);
+			break;
+
+		case BM_MSG_ID_TXABORT:
+			handle_core_msg_txabort(core, &msg->txabort);
+			break;
+
+		case BM_MSG_ID_OVERRUN:
+			handle_core_msg_overrun(core, &msg->overrun);
+			break;
+
+		case BM_MSG_ID_BUSERR:
+			handle_core_msg_buserr(core, &msg->buserr);
+			break;
+
+		case BM_MSG_ID_ERRPASSIVE:
+		case BM_MSG_ID_ERRWARN:
+			handle_core_msg_errstatechange(core,
+						       &msg->errstatechange);
+			break;
+
+		default:
+			/* Ignore all other BM messages (like the CAN-FD messages) */
+			break;
+		}
+
+		core->bmfifo.msg_fifo_tail =
+				(core->bmfifo.msg_fifo_tail + 1) & 0xff;
+	}
+}
+
+/**
+ * acc_card_interrupt() - handle the interrupts of an esdACC FPGA
+ *
+ * @ov: overview module structure
+ * @cores: array of core structures
+ *
+ * This function handles all interrupts pending for the overview module and the
+ * CAN cores of the esdACC FPGA.
+ *
+ * It examines for all cores (the overview module core and the CAN cores)
+ * the bmfifo.irq_cnt and compares it with the previously saved
+ * bmfifo.local_irq_cnt. An IRQ is pending if they differ. The esdACC FPGA
+ * updates the bmfifo.irq_cnt values by DMA.
+ *
+ * The pending interrupts are masked by writing to the IRQ mask register at
+ * ACC_OV_OF_BM_IRQ_MASK. This register has for each core a two bit command
+ * field evaluated as follows:
+ *
+ * Define,   bit pattern: meaning
+ *                    00: no action
+ * ACC_BM_IRQ_UNMASK, 01: unmask interrupt
+ * ACC_BM_IRQ_MASK,   10: mask interrupt
+ *                    11: no action
+ *
+ * For each CAN core with a pending IRQ handle_core_interrupt() handles all
+ * busmaster messages from the message FIFO. The last handled message (FIFO
+ * index) is written to the CAN core to acknowledge its handling.
+ *
+ * Last step is to unmask all interrupts in the FPGA using
+ * ACC_BM_IRQ_UNMASK_ALL.
+ *
+ * Return:
+ *	IRQ_HANDLED, if card generated an interrupt that was handled
+ *	IRQ_NONE, if the interrupt is not ours
+ */
+irqreturn_t acc_card_interrupt(struct acc_ov *ov, struct acc_core *cores)
+{
+	u32 irqmask;
+	int i;
+
+	/* First we look for whom interrupts are pending, card/overview
+	 * or any of the cores. Two bits in irqmask are used for each;
+	 * Each two bit field is set to ACC_BM_IRQ_MASK if an IRQ is
+	 * pending.
+	 */
+	irqmask = 0U;
+	if (READ_ONCE(*ov->bmfifo.irq_cnt) != ov->bmfifo.local_irq_cnt) {
+		irqmask |= ACC_BM_IRQ_MASK;
+		ov->bmfifo.local_irq_cnt = READ_ONCE(*ov->bmfifo.irq_cnt);
+	}
+
+	for (i = 0; i < ov->active_cores; i++) {
+		struct acc_core *core = &cores[i];
+
+		if (READ_ONCE(*core->bmfifo.irq_cnt) != core->bmfifo.local_irq_cnt) {
+			irqmask |= (ACC_BM_IRQ_MASK << (2 * (i + 1)));
+			core->bmfifo.local_irq_cnt = READ_ONCE(*core->bmfifo.irq_cnt);
+		}
+	}
+
+	if (!irqmask)
+		return IRQ_NONE;
+
+	/* At second we tell the card we're working on them by writing irqmask,
+	 * call handle_{ov|core}_interrupt and then acknowledge the
+	 * interrupts by writing irq_cnt:
+	 */
+	acc_ov_write32(ov, ACC_OV_OF_BM_IRQ_MASK, irqmask);
+
+	if (irqmask & ACC_BM_IRQ_MASK) {
+		/* handle_ov_interrupt(); - no use yet. */
+		acc_ov_write32(ov, ACC_OV_OF_BM_IRQ_COUNTER,
+			       ov->bmfifo.local_irq_cnt);
+	}
+
+	for (i = 0; i < ov->active_cores; i++) {
+		struct acc_core *core = &cores[i];
+
+		if (irqmask & (ACC_BM_IRQ_MASK << (2 * (i + 1)))) {
+			handle_core_interrupt(core);
+			acc_write32(core, ACC_OV_OF_BM_IRQ_COUNTER,
+				    core->bmfifo.local_irq_cnt);
+		}
+	}
+
+	acc_ov_write32(ov, ACC_OV_OF_BM_IRQ_MASK, ACC_BM_IRQ_UNMASK_ALL);
+
+	return IRQ_HANDLED;
+}

drivers/net/can/esd/esdacc.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2015 - 2016 Thomas Körper, esd electronic system design gmbh
+ * Copyright (C) 2017 - 2023 Stefan Mätje, esd electronics gmbh
+ */
+
+#include <linux/bits.h>
+#include <linux/can/dev.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/units.h>
+
+#define ACC_TS_FREQ_80MHZ (80 * HZ_PER_MHZ)
+#define ACC_I2C_ADDON_DETECT_DELAY_MS 10
+
+/* esdACC Overview Module */
+#define ACC_OV_OF_PROBE	0x0000
+#define ACC_OV_OF_VERSION 0x0004
+#define ACC_OV_OF_INFO 0x0008
+#define ACC_OV_OF_CANCORE_FREQ 0x000c
+#define ACC_OV_OF_TS_FREQ_LO 0x0010
+#define ACC_OV_OF_TS_FREQ_HI 0x0014
+#define ACC_OV_OF_IRQ_STATUS_CORES 0x0018
+#define ACC_OV_OF_TS_CURR_LO 0x001c
+#define ACC_OV_OF_TS_CURR_HI 0x0020
+#define ACC_OV_OF_IRQ_STATUS 0x0028
+#define ACC_OV_OF_MODE 0x002c
+#define ACC_OV_OF_BM_IRQ_COUNTER 0x0070
+#define ACC_OV_OF_BM_IRQ_MASK 0x0074
+#define ACC_OV_OF_MSI_DATA 0x0080
+#define ACC_OV_OF_MSI_ADDRESSOFFSET 0x0084
+
+/* Feature flags are contained in the upper 16 bit of the version
+ * register at ACC_OV_OF_VERSION but only used with these masks after
+ * extraction into an extra variable => (xx - 16).
+ */
+#define ACC_OV_REG_FEAT_MASK_CANFD BIT(27 - 16)
+#define ACC_OV_REG_FEAT_MASK_NEW_PSC BIT(28 - 16)
+
+#define ACC_OV_REG_MODE_MASK_ENDIAN_LITTLE BIT(0)
+#define ACC_OV_REG_MODE_MASK_BM_ENABLE BIT(1)
+#define ACC_OV_REG_MODE_MASK_MODE_LED BIT(2)
+#define ACC_OV_REG_MODE_MASK_TIMER_ENABLE BIT(4)
+#define ACC_OV_REG_MODE_MASK_TIMER_ONE_SHOT BIT(5)
+#define ACC_OV_REG_MODE_MASK_TIMER_ABSOLUTE BIT(6)
+#define ACC_OV_REG_MODE_MASK_TIMER GENMASK(6, 4)
+#define ACC_OV_REG_MODE_MASK_TS_SRC GENMASK(8, 7)
+#define ACC_OV_REG_MODE_MASK_I2C_ENABLE BIT(11)
+#define ACC_OV_REG_MODE_MASK_MSI_ENABLE BIT(14)
+#define ACC_OV_REG_MODE_MASK_NEW_PSC_ENABLE BIT(15)
+#define ACC_OV_REG_MODE_MASK_FPGA_RESET BIT(31)
+
+/* esdACC CAN Core Module */
+#define ACC_CORE_OF_CTRL_MODE 0x0000
+#define ACC_CORE_OF_STATUS_IRQ 0x0008
+#define ACC_CORE_OF_BRP	0x000c
+#define ACC_CORE_OF_BTR	0x0010
+#define ACC_CORE_OF_FBTR 0x0014
+#define ACC_CORE_OF_STATUS 0x0030
+#define ACC_CORE_OF_TXFIFO_CONFIG 0x0048
+#define ACC_CORE_OF_TXFIFO_STATUS 0x004c
+#define ACC_CORE_OF_TX_STATUS_IRQ 0x0050
+#define ACC_CORE_OF_TX_ABORT_MASK 0x0054
+#define ACC_CORE_OF_BM_IRQ_COUNTER 0x0070
+#define ACC_CORE_OF_TXFIFO_ID 0x00c0
+#define ACC_CORE_OF_TXFIFO_DLC 0x00c4
+#define ACC_CORE_OF_TXFIFO_DATA_0 0x00c8
+#define ACC_CORE_OF_TXFIFO_DATA_1 0x00cc
+
+#define ACC_REG_CONTROL_MASK_MODE_RESETMODE BIT(0)
+#define ACC_REG_CONTROL_MASK_MODE_LOM BIT(1)
+#define ACC_REG_CONTROL_MASK_MODE_STM BIT(2)
+#define ACC_REG_CONTROL_MASK_MODE_TRANSEN BIT(5)
+#define ACC_REG_CONTROL_MASK_MODE_TS BIT(6)
+#define ACC_REG_CONTROL_MASK_MODE_SCHEDULE BIT(7)
+
+#define ACC_REG_CONTROL_MASK_IE_RXTX BIT(8)
+#define ACC_REG_CONTROL_MASK_IE_TXERROR BIT(9)
+#define ACC_REG_CONTROL_MASK_IE_ERRWARN BIT(10)
+#define ACC_REG_CONTROL_MASK_IE_OVERRUN BIT(11)
+#define ACC_REG_CONTROL_MASK_IE_TSI BIT(12)
+#define ACC_REG_CONTROL_MASK_IE_ERRPASS BIT(13)
+#define ACC_REG_CONTROL_MASK_IE_ALI BIT(14)
+#define ACC_REG_CONTROL_MASK_IE_BUSERR BIT(15)
+
+/* BRP and BTR register layout for CAN-Classic version */
+#define ACC_REG_BRP_CL_MASK_BRP GENMASK(8, 0)
+#define ACC_REG_BTR_CL_MASK_TSEG1 GENMASK(3, 0)
+#define ACC_REG_BTR_CL_MASK_TSEG2 GENMASK(18, 16)
+#define ACC_REG_BTR_CL_MASK_SJW GENMASK(25, 24)
+
+/* BRP and BTR register layout for CAN-FD version */
+#define ACC_REG_BRP_FD_MASK_BRP GENMASK(7, 0)
+#define ACC_REG_BTR_FD_MASK_TSEG1 GENMASK(7, 0)
+#define ACC_REG_BTR_FD_MASK_TSEG2 GENMASK(22, 16)
+#define ACC_REG_BTR_FD_MASK_SJW GENMASK(30, 24)
+
+/* 256 BM_MSGs of 32 byte size */
+#define ACC_CORE_DMAMSG_SIZE 32U
+#define ACC_CORE_DMABUF_SIZE (256U * ACC_CORE_DMAMSG_SIZE)
+
+enum acc_bmmsg_id {
+	BM_MSG_ID_RXTXDONE = 0x01,
+	BM_MSG_ID_TXABORT = 0x02,
+	BM_MSG_ID_OVERRUN = 0x03,
+	BM_MSG_ID_BUSERR = 0x04,
+	BM_MSG_ID_ERRPASSIVE = 0x05,
+	BM_MSG_ID_ERRWARN = 0x06,
+	BM_MSG_ID_TIMESLICE = 0x07,
+	BM_MSG_ID_HWTIMER = 0x08,
+	BM_MSG_ID_HOTPLUG = 0x09,
+};
+
+/* The struct acc_bmmsg_* structure declarations that follow here provide
+ * access to the ring buffer of bus master messages maintained by the FPGA
+ * bus master engine. All bus master messages have the same size of
+ * ACC_CORE_DMAMSG_SIZE and a minimum alignment of ACC_CORE_DMAMSG_SIZE in
+ * memory.
+ *
+ * All structure members are natural aligned. Therefore we should not need
+ * a __packed attribute. All struct acc_bmmsg_* declarations have at least
+ * reserved* members to fill the structure to the full ACC_CORE_DMAMSG_SIZE.
+ *
+ * A failure of this property due padding will be detected at compile time
+ * by static_assert(sizeof(union acc_bmmsg) == ACC_CORE_DMAMSG_SIZE).
+ */
+
+struct acc_bmmsg_rxtxdone {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 reserved1[2];
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u32 id;
+	struct {
+		u8 len;
+		u8 txdfifo_idx;
+		u8 zeroes8;
+		u8 reserved;
+	} acc_dlc;
+	u8 data[CAN_MAX_DLEN];
+	/* Time stamps in struct acc_ov::timestamp_frequency ticks. */
+	u64 ts;
+};
+
+struct acc_bmmsg_txabort {
+	u8 msg_id;
+	u8 txfifo_level;
+	u16 abort_mask;
+	u8 txtsfifo_level;
+	u8 reserved2[1];
+	u16 abort_mask_txts;
+	u64 ts;
+	u32 reserved3[4];
+};
+
+struct acc_bmmsg_overrun {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 lost_cnt;
+	u8 reserved1;
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u64 ts;
+	u32 reserved3[4];
+};
+
+struct acc_bmmsg_buserr {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 ecc;
+	u8 reserved1;
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u64 ts;
+	u32 reg_status;
+	u32 reg_btr;
+	u32 reserved3[2];
+};
+
+struct acc_bmmsg_errstatechange {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 reserved1[2];
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u64 ts;
+	u32 reg_status;
+	u32 reserved3[3];
+};
+
+struct acc_bmmsg_timeslice {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 reserved1[2];
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u64 ts;
+	u32 reserved3[4];
+};
+
+struct acc_bmmsg_hwtimer {
+	u8 msg_id;
+	u8 reserved1[3];
+	u32 reserved2[1];
+	u64 timer;
+	u32 reserved3[4];
+};
+
+struct acc_bmmsg_hotplug {
+	u8 msg_id;
+	u8 reserved1[3];
+	u32 reserved2[7];
+};
+
+union acc_bmmsg {
+	u8 msg_id;
+	struct acc_bmmsg_rxtxdone rxtxdone;
+	struct acc_bmmsg_txabort txabort;
+	struct acc_bmmsg_overrun overrun;
+	struct acc_bmmsg_buserr buserr;
+	struct acc_bmmsg_errstatechange errstatechange;
+	struct acc_bmmsg_timeslice timeslice;
+	struct acc_bmmsg_hwtimer hwtimer;
+};
+
+/* Check size of union acc_bmmsg to be of expected size. */
+static_assert(sizeof(union acc_bmmsg) == ACC_CORE_DMAMSG_SIZE);
+
+struct acc_bmfifo {
+	const union acc_bmmsg *messages;
+	/* irq_cnt points to an u32 value where the esdACC FPGA deposits
+	 * the bm_fifo head index in coherent DMA memory. Only bits 7..0
+	 * are valid. Use READ_ONCE() to access this memory location.
+	 */
+	const u32 *irq_cnt;
+	u32 local_irq_cnt;
+	u32 msg_fifo_tail;
+};
+
+struct acc_core {
+	void __iomem *addr;
+	struct net_device *netdev;
+	struct acc_bmfifo bmfifo;
+	u8 tx_fifo_size;
+	u8 tx_fifo_head;
+	u8 tx_fifo_tail;
+};
+
+struct acc_ov {
+	void __iomem *addr;
+	struct acc_bmfifo bmfifo;
+	u32 timestamp_frequency;
+	u32 core_frequency;
+	u16 version;
+	u16 features;
+	u8 total_cores;
+	u8 active_cores;
+};
+
+struct acc_net_priv {
+	struct can_priv can; /* must be the first member! */
+	struct acc_core *core;
+	struct acc_ov *ov;
+};
+
+static inline u32 acc_read32(struct acc_core *core, unsigned short offs)
+{
+	return ioread32be(core->addr + offs);
+}
+
+static inline void acc_write32(struct acc_core *core,
+			       unsigned short offs, u32 v)
+{
+	iowrite32be(v, core->addr + offs);
+}
+
+static inline void acc_write32_noswap(struct acc_core *core,
+				      unsigned short offs, u32 v)
+{
+	iowrite32(v, core->addr + offs);
+}
+
+static inline void acc_set_bits(struct acc_core *core,
+				unsigned short offs, u32 mask)
+{
+	u32 v = acc_read32(core, offs);
+
+	v |= mask;
+	acc_write32(core, offs, v);
+}
+
+static inline void acc_clear_bits(struct acc_core *core,
+				  unsigned short offs, u32 mask)
+{
+	u32 v = acc_read32(core, offs);
+
+	v &= ~mask;
+	acc_write32(core, offs, v);
+}
+
+static inline int acc_resetmode_entered(struct acc_core *core)
+{
+	u32 ctrl = acc_read32(core, ACC_CORE_OF_CTRL_MODE);
+
+	return (ctrl & ACC_REG_CONTROL_MASK_MODE_RESETMODE) != 0;
+}
+
+static inline u32 acc_ov_read32(struct acc_ov *ov, unsigned short offs)
+{
+	return ioread32be(ov->addr + offs);
+}
+
+static inline void acc_ov_write32(struct acc_ov *ov,
+				  unsigned short offs, u32 v)
+{
+	iowrite32be(v, ov->addr + offs);
+}
+
+static inline void acc_ov_set_bits(struct acc_ov *ov,
+				   unsigned short offs, u32 b)
+{
+	u32 v = acc_ov_read32(ov, offs);
+
+	v |= b;
+	acc_ov_write32(ov, offs, v);
+}
+
+static inline void acc_ov_clear_bits(struct acc_ov *ov,
+				     unsigned short offs, u32 b)
+{
+	u32 v = acc_ov_read32(ov, offs);
+
+	v &= ~b;
+	acc_ov_write32(ov, offs, v);
+}
+
+static inline void acc_reset_fpga(struct acc_ov *ov)
+{
+	acc_ov_write32(ov, ACC_OV_OF_MODE, ACC_OV_REG_MODE_MASK_FPGA_RESET);
+
+	/* (Re-)start and wait for completion of addon detection on the I^2C bus */
+	acc_ov_set_bits(ov, ACC_OV_OF_MODE, ACC_OV_REG_MODE_MASK_I2C_ENABLE);
+	mdelay(ACC_I2C_ADDON_DETECT_DELAY_MS);
+}
+
+void acc_init_ov(struct acc_ov *ov, struct device *dev);
+void acc_init_bm_ptr(struct acc_ov *ov, struct acc_core *cores,
+		     const void *mem);
+int acc_open(struct net_device *netdev);
+int acc_close(struct net_device *netdev);
+netdev_tx_t acc_start_xmit(struct sk_buff *skb, struct net_device *netdev);
+int acc_get_berr_counter(const struct net_device *netdev,
+			 struct can_berr_counter *bec);
+int acc_set_mode(struct net_device *netdev, enum can_mode mode);
+int acc_set_bittiming(struct net_device *netdev);
+irqreturn_t acc_card_interrupt(struct acc_ov *ov, struct acc_core *cores);

drivers/net/can/kvaser_pciefd.c

@@ -47,12 +47,18 @@ MODULE_DESCRIPTION("CAN driver for Kvaser CAN/PCIe devices");
 #define KVASER_PCIEFD_MINIPCIE_2CAN_V3_DEVICE_ID 0x0015
 #define KVASER_PCIEFD_MINIPCIE_1CAN_V3_DEVICE_ID 0x0016
 
+/* Xilinx based devices */
+#define KVASER_PCIEFD_M2_4CAN_DEVICE_ID 0x0017
+
 /* Altera SerDes Enable 64-bit DMA address translation */
 #define KVASER_PCIEFD_ALTERA_DMA_64BIT BIT(0)
 
 /* SmartFusion2 SerDes LSB address translation mask */
 #define KVASER_PCIEFD_SF2_DMA_LSB_MASK GENMASK(31, 12)
 
+/* Xilinx SerDes LSB address translation mask */
+#define KVASER_PCIEFD_XILINX_DMA_LSB_MASK GENMASK(31, 12)
+
 /* Kvaser KCAN CAN controller registers */
 #define KVASER_PCIEFD_KCAN_FIFO_REG 0x100
 #define KVASER_PCIEFD_KCAN_FIFO_LAST_REG 0x180
@@ -281,6 +287,8 @@ static void kvaser_pciefd_write_dma_map_altera(struct kvaser_pciefd *pcie,
 					       dma_addr_t addr, int index);
 static void kvaser_pciefd_write_dma_map_sf2(struct kvaser_pciefd *pcie,
 					    dma_addr_t addr, int index);
+static void kvaser_pciefd_write_dma_map_xilinx(struct kvaser_pciefd *pcie,
+					       dma_addr_t addr, int index);
 
 struct kvaser_pciefd_address_offset {
 	u32 serdes;
@@ -335,6 +343,18 @@ static const struct kvaser_pciefd_address_offset kvaser_pciefd_sf2_address_offse
 	.kcan_ch1 = 0x142000,
 };
 
+static const struct kvaser_pciefd_address_offset kvaser_pciefd_xilinx_address_offset = {
+	.serdes = 0x00208,
+	.pci_ien = 0x102004,
+	.pci_irq = 0x102008,
+	.sysid = 0x100000,
+	.loopback = 0x103000,
+	.kcan_srb_fifo = 0x120000,
+	.kcan_srb = 0x121000,
+	.kcan_ch0 = 0x140000,
+	.kcan_ch1 = 0x142000,
+};
+
 static const struct kvaser_pciefd_irq_mask kvaser_pciefd_altera_irq_mask = {
 	.kcan_rx0 = BIT(4),
 	.kcan_tx = { BIT(0), BIT(1), BIT(2), BIT(3) },
@@ -347,6 +367,12 @@ static const struct kvaser_pciefd_irq_mask kvaser_pciefd_sf2_irq_mask = {
 	.all = GENMASK(19, 16) | BIT(4),
 };
 
+static const struct kvaser_pciefd_irq_mask kvaser_pciefd_xilinx_irq_mask = {
+	.kcan_rx0 = BIT(4),
+	.kcan_tx = { BIT(16), BIT(17), BIT(18), BIT(19) },
+	.all = GENMASK(19, 16) | BIT(4),
+};
+
 static const struct kvaser_pciefd_dev_ops kvaser_pciefd_altera_dev_ops = {
 	.kvaser_pciefd_write_dma_map = kvaser_pciefd_write_dma_map_altera,
 };
@@ -355,6 +381,10 @@ static const struct kvaser_pciefd_dev_ops kvaser_pciefd_sf2_dev_ops = {
 	.kvaser_pciefd_write_dma_map = kvaser_pciefd_write_dma_map_sf2,
 };
 
+static const struct kvaser_pciefd_dev_ops kvaser_pciefd_xilinx_dev_ops = {
+	.kvaser_pciefd_write_dma_map = kvaser_pciefd_write_dma_map_xilinx,
+};
+
 static const struct kvaser_pciefd_driver_data kvaser_pciefd_altera_driver_data = {
 	.address_offset = &kvaser_pciefd_altera_address_offset,
 	.irq_mask = &kvaser_pciefd_altera_irq_mask,
@@ -367,6 +397,12 @@ static const struct kvaser_pciefd_driver_data kvaser_pciefd_sf2_driver_data = {
 	.ops = &kvaser_pciefd_sf2_dev_ops,
 };
 
+static const struct kvaser_pciefd_driver_data kvaser_pciefd_xilinx_driver_data = {
+	.address_offset = &kvaser_pciefd_xilinx_address_offset,
+	.irq_mask = &kvaser_pciefd_xilinx_irq_mask,
+	.ops = &kvaser_pciefd_xilinx_dev_ops,
+};
+
 struct kvaser_pciefd_can {
 	struct can_priv can;
 	struct kvaser_pciefd *kv_pcie;
@@ -456,6 +492,10 @@ static struct pci_device_id kvaser_pciefd_id_table[] = {
 		PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_1CAN_V3_DEVICE_ID),
 		.driver_data = (kernel_ulong_t)&kvaser_pciefd_sf2_driver_data,
 	},
+	{
+		PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_M2_4CAN_DEVICE_ID),
+		.driver_data = (kernel_ulong_t)&kvaser_pciefd_xilinx_driver_data,
+	},
 	{
 		0,
 	},
@@ -1035,6 +1075,21 @@ static void kvaser_pciefd_write_dma_map_sf2(struct kvaser_pciefd *pcie,
 	iowrite32(msb, serdes_base + 0x4);
 }
 
+static void kvaser_pciefd_write_dma_map_xilinx(struct kvaser_pciefd *pcie,
+					       dma_addr_t addr, int index)
+{
+	void __iomem *serdes_base;
+	u32 lsb = addr & KVASER_PCIEFD_XILINX_DMA_LSB_MASK;
+	u32 msb = 0x0;
+
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+	msb = addr >> 32;
+#endif
+	serdes_base = KVASER_PCIEFD_SERDES_ADDR(pcie) + 0x8 * index;
+	iowrite32(msb, serdes_base);
+	iowrite32(lsb, serdes_base + 0x4);
+}
+
 static int kvaser_pciefd_setup_dma(struct kvaser_pciefd *pcie)
 {
 	int i;

drivers/net/can/m_can/m_can.c

@@ -255,6 +255,7 @@ enum m_can_reg {
 #define TXESC_TBDS_64B		0x7
 
 /* Tx Event FIFO Configuration (TXEFC) */
+#define TXEFC_EFWM_MASK		GENMASK(29, 24)
 #define TXEFC_EFS_MASK		GENMASK(21, 16)
 
 /* Tx Event FIFO Status (TXEFS) */
@@ -320,6 +321,12 @@ struct id_and_dlc {
 	u32 dlc;
 };
 
+struct m_can_fifo_element {
+	u32 id;
+	u32 dlc;
+	u8 data[CANFD_MAX_DLEN];
+};
+
 static inline u32 m_can_read(struct m_can_classdev *cdev, enum m_can_reg reg)
 {
 	return cdev->ops->read_reg(cdev, reg);
@@ -372,16 +379,6 @@ m_can_txe_fifo_read(struct m_can_classdev *cdev, u32 fgi, u32 offset, u32 *val)
 	return cdev->ops->read_fifo(cdev, addr_offset, val, 1);
 }
 
-static inline bool _m_can_tx_fifo_full(u32 txfqs)
-{
-	return !!(txfqs & TXFQS_TFQF);
-}
-
-static inline bool m_can_tx_fifo_full(struct m_can_classdev *cdev)
-{
-	return _m_can_tx_fifo_full(m_can_read(cdev, M_CAN_TXFQS));
-}
-
 static void m_can_config_endisable(struct m_can_classdev *cdev, bool enable)
 {
 	u32 cccr = m_can_read(cdev, M_CAN_CCCR);
@@ -416,15 +413,48 @@ static void m_can_config_endisable(struct m_can_classdev *cdev, bool enable)
 	}
 }
 
+static void m_can_interrupt_enable(struct m_can_classdev *cdev, u32 interrupts)
+{
+	if (cdev->active_interrupts == interrupts)
+		return;
+	cdev->ops->write_reg(cdev, M_CAN_IE, interrupts);
+	cdev->active_interrupts = interrupts;
+}
+
+static void m_can_coalescing_disable(struct m_can_classdev *cdev)
+{
+	u32 new_interrupts = cdev->active_interrupts | IR_RF0N | IR_TEFN;
+
+	if (!cdev->net->irq)
+		return;
+
+	hrtimer_cancel(&cdev->hrtimer);
+	m_can_interrupt_enable(cdev, new_interrupts);
+}
+
 static inline void m_can_enable_all_interrupts(struct m_can_classdev *cdev)
 {
+	if (!cdev->net->irq) {
+		dev_dbg(cdev->dev, "Start hrtimer\n");
+		hrtimer_start(&cdev->hrtimer,
+			      ms_to_ktime(HRTIMER_POLL_INTERVAL_MS),
+			      HRTIMER_MODE_REL_PINNED);
+	}
+
 	/* Only interrupt line 0 is used in this driver */
 	m_can_write(cdev, M_CAN_ILE, ILE_EINT0);
 }
 
 static inline void m_can_disable_all_interrupts(struct m_can_classdev *cdev)
 {
+	m_can_coalescing_disable(cdev);
 	m_can_write(cdev, M_CAN_ILE, 0x0);
+	cdev->active_interrupts = 0x0;
+
+	if (!cdev->net->irq) {
+		dev_dbg(cdev->dev, "Stop hrtimer\n");
+		hrtimer_cancel(&cdev->hrtimer);
+	}
 }
 
 /* Retrieve internal timestamp counter from TSCV.TSC, and shift it to 32-bit
@@ -444,18 +474,26 @@ static u32 m_can_get_timestamp(struct m_can_classdev *cdev)
 static void m_can_clean(struct net_device *net)
 {
 	struct m_can_classdev *cdev = netdev_priv(net);
+	unsigned long irqflags;
 
-	if (cdev->tx_skb) {
-		int putidx = 0;
-
-		net->stats.tx_errors++;
-		if (cdev->version > 30)
-			putidx = FIELD_GET(TXFQS_TFQPI_MASK,
-					   m_can_read(cdev, M_CAN_TXFQS));
+	if (cdev->tx_ops) {
+		for (int i = 0; i != cdev->tx_fifo_size; ++i) {
+			if (!cdev->tx_ops[i].skb)
+				continue;
 
-		can_free_echo_skb(cdev->net, putidx, NULL);
-		cdev->tx_skb = NULL;
+			net->stats.tx_errors++;
+			cdev->tx_ops[i].skb = NULL;
+		}
 	}
+
+	for (int i = 0; i != cdev->can.echo_skb_max; ++i)
+		can_free_echo_skb(cdev->net, i, NULL);
+
+	netdev_reset_queue(cdev->net);
+
+	spin_lock_irqsave(&cdev->tx_handling_spinlock, irqflags);
+	cdev->tx_fifo_in_flight = 0;
+	spin_unlock_irqrestore(&cdev->tx_handling_spinlock, irqflags);
 }
 
 /* For peripherals, pass skb to rx-offload, which will push skb from
@@ -1007,23 +1045,60 @@ static int m_can_poll(struct napi_struct *napi, int quota)
  * echo. timestamp is used for peripherals to ensure correct ordering
  * by rx-offload, and is ignored for non-peripherals.
  */
-static void m_can_tx_update_stats(struct m_can_classdev *cdev,
-				  unsigned int msg_mark,
-				  u32 timestamp)
+static unsigned int m_can_tx_update_stats(struct m_can_classdev *cdev,
+					  unsigned int msg_mark, u32 timestamp)
 {
 	struct net_device *dev = cdev->net;
 	struct net_device_stats *stats = &dev->stats;
+	unsigned int frame_len;
 
 	if (cdev->is_peripheral)
 		stats->tx_bytes +=
 			can_rx_offload_get_echo_skb_queue_timestamp(&cdev->offload,
 								    msg_mark,
 								    timestamp,
-								    NULL);
+								    &frame_len);
 	else
-		stats->tx_bytes += can_get_echo_skb(dev, msg_mark, NULL);
+		stats->tx_bytes += can_get_echo_skb(dev, msg_mark, &frame_len);
 
 	stats->tx_packets++;
+
+	return frame_len;
+}
+
+static void m_can_finish_tx(struct m_can_classdev *cdev, int transmitted,
+			    unsigned int transmitted_frame_len)
+{
+	unsigned long irqflags;
+
+	netdev_completed_queue(cdev->net, transmitted, transmitted_frame_len);
+
+	spin_lock_irqsave(&cdev->tx_handling_spinlock, irqflags);
+	if (cdev->tx_fifo_in_flight >= cdev->tx_fifo_size && transmitted > 0)
+		netif_wake_queue(cdev->net);
+	cdev->tx_fifo_in_flight -= transmitted;
+	spin_unlock_irqrestore(&cdev->tx_handling_spinlock, irqflags);
+}
+
+static netdev_tx_t m_can_start_tx(struct m_can_classdev *cdev)
+{
+	unsigned long irqflags;
+	int tx_fifo_in_flight;
+
+	spin_lock_irqsave(&cdev->tx_handling_spinlock, irqflags);
+	tx_fifo_in_flight = cdev->tx_fifo_in_flight + 1;
+	if (tx_fifo_in_flight >= cdev->tx_fifo_size) {
+		netif_stop_queue(cdev->net);
+		if (tx_fifo_in_flight > cdev->tx_fifo_size) {
+			netdev_err_once(cdev->net, "hard_xmit called while TX FIFO full\n");
+			spin_unlock_irqrestore(&cdev->tx_handling_spinlock, irqflags);
+			return NETDEV_TX_BUSY;
+		}
+	}
+	cdev->tx_fifo_in_flight = tx_fifo_in_flight;
+	spin_unlock_irqrestore(&cdev->tx_handling_spinlock, irqflags);
+
+	return NETDEV_TX_OK;
 }
 
 static int m_can_echo_tx_event(struct net_device *dev)
@@ -1035,6 +1110,8 @@ static int m_can_echo_tx_event(struct net_device *dev)
 	int i = 0;
 	int err = 0;
 	unsigned int msg_mark;
+	int processed = 0;
+	unsigned int processed_frame_len = 0;
 
 	struct m_can_classdev *cdev = netdev_priv(dev);
 
@@ -1063,25 +1140,62 @@ static int m_can_echo_tx_event(struct net_device *dev)
 		fgi = (++fgi >= cdev->mcfg[MRAM_TXE].num ? 0 : fgi);
 
 		/* update stats */
-		m_can_tx_update_stats(cdev, msg_mark, timestamp);
+		processed_frame_len += m_can_tx_update_stats(cdev, msg_mark,
+							     timestamp);
+
+		++processed;
 	}
 
 	if (ack_fgi != -1)
 		m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK,
 							  ack_fgi));
 
+	m_can_finish_tx(cdev, processed, processed_frame_len);
+
 	return err;
 }
 
+static void m_can_coalescing_update(struct m_can_classdev *cdev, u32 ir)
+{
+	u32 new_interrupts = cdev->active_interrupts;
+	bool enable_rx_timer = false;
+	bool enable_tx_timer = false;
+
+	if (!cdev->net->irq)
+		return;
+
+	if (cdev->rx_coalesce_usecs_irq > 0 && (ir & (IR_RF0N | IR_RF0W))) {
+		enable_rx_timer = true;
+		new_interrupts &= ~IR_RF0N;
+	}
+	if (cdev->tx_coalesce_usecs_irq > 0 && (ir & (IR_TEFN | IR_TEFW))) {
+		enable_tx_timer = true;
+		new_interrupts &= ~IR_TEFN;
+	}
+	if (!enable_rx_timer && !hrtimer_active(&cdev->hrtimer))
+		new_interrupts |= IR_RF0N;
+	if (!enable_tx_timer && !hrtimer_active(&cdev->hrtimer))
+		new_interrupts |= IR_TEFN;
+
+	m_can_interrupt_enable(cdev, new_interrupts);
+	if (enable_rx_timer | enable_tx_timer)
+		hrtimer_start(&cdev->hrtimer, cdev->irq_timer_wait,
+			      HRTIMER_MODE_REL);
+}
+
 static irqreturn_t m_can_isr(int irq, void *dev_id)
 {
 	struct net_device *dev = (struct net_device *)dev_id;
 	struct m_can_classdev *cdev = netdev_priv(dev);
 	u32 ir;
 
-	if (pm_runtime_suspended(cdev->dev))
+	if (pm_runtime_suspended(cdev->dev)) {
+		m_can_coalescing_disable(cdev);
 		return IRQ_NONE;
+	}
+
 	ir = m_can_read(cdev, M_CAN_IR);
+	m_can_coalescing_update(cdev, ir);
 	if (!ir)
 		return IRQ_NONE;
 
@@ -1096,13 +1210,17 @@ static irqreturn_t m_can_isr(int irq, void *dev_id)
 	 * - state change IRQ
 	 * - bus error IRQ and bus error reporting
 	 */
-	if ((ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) {
+	if (ir & (IR_RF0N | IR_RF0W | IR_ERR_ALL_30X)) {
 		cdev->irqstatus = ir;
 		if (!cdev->is_peripheral) {
 			m_can_disable_all_interrupts(cdev);
 			napi_schedule(&cdev->napi);
-		} else if (m_can_rx_peripheral(dev, ir) < 0) {
-			goto out_fail;
+		} else {
+			int pkts;
+
+			pkts = m_can_rx_peripheral(dev, ir);
+			if (pkts < 0)
+				goto out_fail;
 		}
 	}
 
@@ -1110,21 +1228,18 @@ static irqreturn_t m_can_isr(int irq, void *dev_id)
 		if (ir & IR_TC) {
 			/* Transmission Complete Interrupt*/
 			u32 timestamp = 0;
+			unsigned int frame_len;
 
 			if (cdev->is_peripheral)
 				timestamp = m_can_get_timestamp(cdev);
-			m_can_tx_update_stats(cdev, 0, timestamp);
-			netif_wake_queue(dev);
+			frame_len = m_can_tx_update_stats(cdev, 0, timestamp);
+			m_can_finish_tx(cdev, 1, frame_len);
 		}
 	} else  {
-		if (ir & IR_TEFN) {
+		if (ir & (IR_TEFN | IR_TEFW)) {
 			/* New TX FIFO Element arrived */
 			if (m_can_echo_tx_event(dev) != 0)
 				goto out_fail;
-
-			if (netif_queue_stopped(dev) &&
-			    !m_can_tx_fifo_full(cdev))
-				netif_wake_queue(dev);
 		}
 	}
 
@@ -1138,6 +1253,15 @@ static irqreturn_t m_can_isr(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static enum hrtimer_restart m_can_coalescing_timer(struct hrtimer *timer)
+{
+	struct m_can_classdev *cdev = container_of(timer, struct m_can_classdev, hrtimer);
+
+	irq_wake_thread(cdev->net->irq, cdev->net);
+
+	return HRTIMER_NORESTART;
+}
+
 static const struct can_bittiming_const m_can_bittiming_const_30X = {
 	.name = KBUILD_MODNAME,
 	.tseg1_min = 2,		/* Time segment 1 = prop_seg + phase_seg1 */
@@ -1276,9 +1400,8 @@ static int m_can_chip_config(struct net_device *dev)
 	}
 
 	/* Disable unused interrupts */
-	interrupts &= ~(IR_ARA | IR_ELO | IR_DRX | IR_TEFF | IR_TEFW | IR_TFE |
-			IR_TCF | IR_HPM | IR_RF1F | IR_RF1W | IR_RF1N |
-			IR_RF0F | IR_RF0W);
+	interrupts &= ~(IR_ARA | IR_ELO | IR_DRX | IR_TEFF | IR_TFE | IR_TCF |
+			IR_HPM | IR_RF1F | IR_RF1W | IR_RF1N | IR_RF0F);
 
 	m_can_config_endisable(cdev, true);
 
@@ -1315,6 +1438,8 @@ static int m_can_chip_config(struct net_device *dev)
 	} else {
 		/* Full TX Event FIFO is used */
 		m_can_write(cdev, M_CAN_TXEFC,
+			    FIELD_PREP(TXEFC_EFWM_MASK,
+				       cdev->tx_max_coalesced_frames_irq) |
 			    FIELD_PREP(TXEFC_EFS_MASK,
 				       cdev->mcfg[MRAM_TXE].num) |
 			    cdev->mcfg[MRAM_TXE].off);
@@ -1322,6 +1447,7 @@ static int m_can_chip_config(struct net_device *dev)
 
 	/* rx fifo configuration, blocking mode, fifo size 1 */
 	m_can_write(cdev, M_CAN_RXF0C,
+		    FIELD_PREP(RXFC_FWM_MASK, cdev->rx_max_coalesced_frames_irq) |
 		    FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF0].num) |
 		    cdev->mcfg[MRAM_RXF0].off);
 
@@ -1380,7 +1506,7 @@ static int m_can_chip_config(struct net_device *dev)
 		else
 			interrupts &= ~(IR_ERR_LEC_31X);
 	}
-	m_can_write(cdev, M_CAN_IE, interrupts);
+	m_can_interrupt_enable(cdev, interrupts);
 
 	/* route all interrupts to INT0 */
 	m_can_write(cdev, M_CAN_ILS, ILS_ALL_INT0);
@@ -1413,15 +1539,16 @@ static int m_can_start(struct net_device *dev)
 	if (ret)
 		return ret;
 
+	netdev_queue_set_dql_min_limit(netdev_get_tx_queue(cdev->net, 0),
+				       cdev->tx_max_coalesced_frames);
+
 	cdev->can.state = CAN_STATE_ERROR_ACTIVE;
 
 	m_can_enable_all_interrupts(cdev);
 
-	if (!dev->irq) {
-		dev_dbg(cdev->dev, "Start hrtimer\n");
-		hrtimer_start(&cdev->hrtimer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS),
-			      HRTIMER_MODE_REL_PINNED);
-	}
+	if (cdev->version > 30)
+		cdev->tx_fifo_putidx = FIELD_GET(TXFQS_TFQPI_MASK,
+						 m_can_read(cdev, M_CAN_TXFQS));
 
 	return 0;
 }
@@ -1577,11 +1704,6 @@ static void m_can_stop(struct net_device *dev)
 {
 	struct m_can_classdev *cdev = netdev_priv(dev);
 
-	if (!dev->irq) {
-		dev_dbg(cdev->dev, "Stop hrtimer\n");
-		hrtimer_cancel(&cdev->hrtimer);
-	}
-
 	/* disable all interrupts */
 	m_can_disable_all_interrupts(cdev);
 
@@ -1605,8 +1727,9 @@ static int m_can_close(struct net_device *dev)
 	m_can_clk_stop(cdev);
 	free_irq(dev->irq, dev);
 
+	m_can_clean(dev);
+
 	if (cdev->is_peripheral) {
-		cdev->tx_skb = NULL;
 		destroy_workqueue(cdev->tx_wq);
 		cdev->tx_wq = NULL;
 		can_rx_offload_disable(&cdev->offload);
@@ -1619,57 +1742,42 @@ static int m_can_close(struct net_device *dev)
 	return 0;
 }
 
-static int m_can_next_echo_skb_occupied(struct net_device *dev, int putidx)
-{
-	struct m_can_classdev *cdev = netdev_priv(dev);
-	/*get wrap around for loopback skb index */
-	unsigned int wrap = cdev->can.echo_skb_max;
-	int next_idx;
-
-	/* calculate next index */
-	next_idx = (++putidx >= wrap ? 0 : putidx);
-
-	/* check if occupied */
-	return !!cdev->can.echo_skb[next_idx];
-}
-
-static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev)
+static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev,
+				    struct sk_buff *skb)
 {
-	struct canfd_frame *cf = (struct canfd_frame *)cdev->tx_skb->data;
+	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
+	u8 len_padded = DIV_ROUND_UP(cf->len, 4);
+	struct m_can_fifo_element fifo_element;
 	struct net_device *dev = cdev->net;
-	struct sk_buff *skb = cdev->tx_skb;
-	struct id_and_dlc fifo_header;
 	u32 cccr, fdflags;
-	u32 txfqs;
 	int err;
-	int putidx;
-
-	cdev->tx_skb = NULL;
+	u32 putidx;
+	unsigned int frame_len = can_skb_get_frame_len(skb);
 
 	/* Generate ID field for TX buffer Element */
 	/* Common to all supported M_CAN versions */
 	if (cf->can_id & CAN_EFF_FLAG) {
-		fifo_header.id = cf->can_id & CAN_EFF_MASK;
-		fifo_header.id |= TX_BUF_XTD;
+		fifo_element.id = cf->can_id & CAN_EFF_MASK;
+		fifo_element.id |= TX_BUF_XTD;
 	} else {
-		fifo_header.id = ((cf->can_id & CAN_SFF_MASK) << 18);
+		fifo_element.id = ((cf->can_id & CAN_SFF_MASK) << 18);
 	}
 
 	if (cf->can_id & CAN_RTR_FLAG)
-		fifo_header.id |= TX_BUF_RTR;
+		fifo_element.id |= TX_BUF_RTR;
 
 	if (cdev->version == 30) {
 		netif_stop_queue(dev);
 
-		fifo_header.dlc = can_fd_len2dlc(cf->len) << 16;
+		fifo_element.dlc = can_fd_len2dlc(cf->len) << 16;
 
 		/* Write the frame ID, DLC, and payload to the FIFO element. */
-		err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_ID, &fifo_header, 2);
+		err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_ID, &fifo_element, 2);
 		if (err)
 			goto out_fail;
 
 		err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_DATA,
-				       cf->data, DIV_ROUND_UP(cf->len, 4));
+				       cf->data, len_padded);
 		if (err)
 			goto out_fail;
 
@@ -1690,33 +1798,15 @@ static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev)
 		}
 		m_can_write(cdev, M_CAN_TXBTIE, 0x1);
 
-		can_put_echo_skb(skb, dev, 0, 0);
+		can_put_echo_skb(skb, dev, 0, frame_len);
 
 		m_can_write(cdev, M_CAN_TXBAR, 0x1);
 		/* End of xmit function for version 3.0.x */
 	} else {
 		/* Transmit routine for version >= v3.1.x */
 
-		txfqs = m_can_read(cdev, M_CAN_TXFQS);
-
-		/* Check if FIFO full */
-		if (_m_can_tx_fifo_full(txfqs)) {
-			/* This shouldn't happen */
-			netif_stop_queue(dev);
-			netdev_warn(dev,
-				    "TX queue active although FIFO is full.");
-
-			if (cdev->is_peripheral) {
-				kfree_skb(skb);
-				dev->stats.tx_dropped++;
-				return NETDEV_TX_OK;
-			} else {
-				return NETDEV_TX_BUSY;
-			}
-		}
-
 		/* get put index for frame */
-		putidx = FIELD_GET(TXFQS_TFQPI_MASK, txfqs);
+		putidx = cdev->tx_fifo_putidx;
 
 		/* Construct DLC Field, with CAN-FD configuration.
 		 * Use the put index of the fifo as the message marker,
@@ -1731,30 +1821,32 @@ static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev)
 				fdflags |= TX_BUF_BRS;
 		}
 
-		fifo_header.dlc = FIELD_PREP(TX_BUF_MM_MASK, putidx) |
+		fifo_element.dlc = FIELD_PREP(TX_BUF_MM_MASK, putidx) |
 			FIELD_PREP(TX_BUF_DLC_MASK, can_fd_len2dlc(cf->len)) |
 			fdflags | TX_BUF_EFC;
-		err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_ID, &fifo_header, 2);
-		if (err)
-			goto out_fail;
 
-		err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DATA,
-				       cf->data, DIV_ROUND_UP(cf->len, 4));
+		memcpy_and_pad(fifo_element.data, CANFD_MAX_DLEN, &cf->data,
+			       cf->len, 0);
+
+		err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_ID,
+				       &fifo_element, 2 + len_padded);
 		if (err)
 			goto out_fail;
 
 		/* Push loopback echo.
 		 * Will be looped back on TX interrupt based on message marker
 		 */
-		can_put_echo_skb(skb, dev, putidx, 0);
-
-		/* Enable TX FIFO element to start transfer  */
-		m_can_write(cdev, M_CAN_TXBAR, (1 << putidx));
+		can_put_echo_skb(skb, dev, putidx, frame_len);
 
-		/* stop network queue if fifo full */
-		if (m_can_tx_fifo_full(cdev) ||
-		    m_can_next_echo_skb_occupied(dev, putidx))
-			netif_stop_queue(dev);
+		if (cdev->is_peripheral) {
+			/* Delay enabling TX FIFO element */
+			cdev->tx_peripheral_submit |= BIT(putidx);
+		} else {
+			/* Enable TX FIFO element to start transfer  */
+			m_can_write(cdev, M_CAN_TXBAR, BIT(putidx));
+		}
+		cdev->tx_fifo_putidx = (++cdev->tx_fifo_putidx >= cdev->can.echo_skb_max ?
+					0 : cdev->tx_fifo_putidx);
 	}
 
 	return NETDEV_TX_OK;
@@ -1765,46 +1857,91 @@ static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev)
 	return NETDEV_TX_BUSY;
 }
 
+static void m_can_tx_submit(struct m_can_classdev *cdev)
+{
+	if (cdev->version == 30)
+		return;
+	if (!cdev->is_peripheral)
+		return;
+
+	m_can_write(cdev, M_CAN_TXBAR, cdev->tx_peripheral_submit);
+	cdev->tx_peripheral_submit = 0;
+}
+
 static void m_can_tx_work_queue(struct work_struct *ws)
 {
-	struct m_can_classdev *cdev = container_of(ws, struct m_can_classdev,
-						   tx_work);
+	struct m_can_tx_op *op = container_of(ws, struct m_can_tx_op, work);
+	struct m_can_classdev *cdev = op->cdev;
+	struct sk_buff *skb = op->skb;
+
+	op->skb = NULL;
+	m_can_tx_handler(cdev, skb);
+	if (op->submit)
+		m_can_tx_submit(cdev);
+}
+
+static void m_can_tx_queue_skb(struct m_can_classdev *cdev, struct sk_buff *skb,
+			       bool submit)
+{
+	cdev->tx_ops[cdev->next_tx_op].skb = skb;
+	cdev->tx_ops[cdev->next_tx_op].submit = submit;
+	queue_work(cdev->tx_wq, &cdev->tx_ops[cdev->next_tx_op].work);
+
+	++cdev->next_tx_op;
+	if (cdev->next_tx_op >= cdev->tx_fifo_size)
+		cdev->next_tx_op = 0;
+}
+
+static netdev_tx_t m_can_start_peripheral_xmit(struct m_can_classdev *cdev,
+					       struct sk_buff *skb)
+{
+	bool submit;
+
+	++cdev->nr_txs_without_submit;
+	if (cdev->nr_txs_without_submit >= cdev->tx_max_coalesced_frames ||
+	    !netdev_xmit_more()) {
+		cdev->nr_txs_without_submit = 0;
+		submit = true;
+	} else {
+		submit = false;
+	}
+	m_can_tx_queue_skb(cdev, skb, submit);
 
-	m_can_tx_handler(cdev);
+	return NETDEV_TX_OK;
 }
 
 static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
 				    struct net_device *dev)
 {
 	struct m_can_classdev *cdev = netdev_priv(dev);
+	unsigned int frame_len;
+	netdev_tx_t ret;
 
 	if (can_dev_dropped_skb(dev, skb))
 		return NETDEV_TX_OK;
 
-	if (cdev->is_peripheral) {
-		if (cdev->tx_skb) {
-			netdev_err(dev, "hard_xmit called while tx busy\n");
-			return NETDEV_TX_BUSY;
-		}
+	frame_len = can_skb_get_frame_len(skb);
 
-		if (cdev->can.state == CAN_STATE_BUS_OFF) {
-			m_can_clean(dev);
-		} else {
-			/* Need to stop the queue to avoid numerous requests
-			 * from being sent.  Suggested improvement is to create
-			 * a queueing mechanism that will queue the skbs and
-			 * process them in order.
-			 */
-			cdev->tx_skb = skb;
-			netif_stop_queue(cdev->net);
-			queue_work(cdev->tx_wq, &cdev->tx_work);
-		}
-	} else {
-		cdev->tx_skb = skb;
-		return m_can_tx_handler(cdev);
+	if (cdev->can.state == CAN_STATE_BUS_OFF) {
+		m_can_clean(cdev->net);
+		return NETDEV_TX_OK;
 	}
 
-	return NETDEV_TX_OK;
+	ret = m_can_start_tx(cdev);
+	if (ret != NETDEV_TX_OK)
+		return ret;
+
+	netdev_sent_queue(dev, frame_len);
+
+	if (cdev->is_peripheral)
+		ret = m_can_start_peripheral_xmit(cdev, skb);
+	else
+		ret = m_can_tx_handler(cdev, skb);
+
+	if (ret != NETDEV_TX_OK)
+		netdev_completed_queue(dev, 1, frame_len);
+
+	return ret;
 }
 
 static enum hrtimer_restart hrtimer_callback(struct hrtimer *timer)
@@ -1844,15 +1981,17 @@ static int m_can_open(struct net_device *dev)
 
 	/* register interrupt handler */
 	if (cdev->is_peripheral) {
-		cdev->tx_skb = NULL;
-		cdev->tx_wq = alloc_workqueue("mcan_wq",
-					      WQ_FREEZABLE | WQ_MEM_RECLAIM, 0);
+		cdev->tx_wq = alloc_ordered_workqueue("mcan_wq",
+						      WQ_FREEZABLE | WQ_MEM_RECLAIM);
 		if (!cdev->tx_wq) {
 			err = -ENOMEM;
 			goto out_wq_fail;
 		}
 
-		INIT_WORK(&cdev->tx_work, m_can_tx_work_queue);
+		for (int i = 0; i != cdev->tx_fifo_size; ++i) {
+			cdev->tx_ops[i].cdev = cdev;
+			INIT_WORK(&cdev->tx_ops[i].work, m_can_tx_work_queue);
+		}
 
 		err = request_threaded_irq(dev->irq, NULL, m_can_isr,
 					   IRQF_ONESHOT,
@@ -1900,7 +2039,108 @@ static const struct net_device_ops m_can_netdev_ops = {
 	.ndo_change_mtu = can_change_mtu,
 };
 
+static int m_can_get_coalesce(struct net_device *dev,
+			      struct ethtool_coalesce *ec,
+			      struct kernel_ethtool_coalesce *kec,
+			      struct netlink_ext_ack *ext_ack)
+{
+	struct m_can_classdev *cdev = netdev_priv(dev);
+
+	ec->rx_max_coalesced_frames_irq = cdev->rx_max_coalesced_frames_irq;
+	ec->rx_coalesce_usecs_irq = cdev->rx_coalesce_usecs_irq;
+	ec->tx_max_coalesced_frames = cdev->tx_max_coalesced_frames;
+	ec->tx_max_coalesced_frames_irq = cdev->tx_max_coalesced_frames_irq;
+	ec->tx_coalesce_usecs_irq = cdev->tx_coalesce_usecs_irq;
+
+	return 0;
+}
+
+static int m_can_set_coalesce(struct net_device *dev,
+			      struct ethtool_coalesce *ec,
+			      struct kernel_ethtool_coalesce *kec,
+			      struct netlink_ext_ack *ext_ack)
+{
+	struct m_can_classdev *cdev = netdev_priv(dev);
+
+	if (cdev->can.state != CAN_STATE_STOPPED) {
+		netdev_err(dev, "Device is in use, please shut it down first\n");
+		return -EBUSY;
+	}
+
+	if (ec->rx_max_coalesced_frames_irq > cdev->mcfg[MRAM_RXF0].num) {
+		netdev_err(dev, "rx-frames-irq %u greater than the RX FIFO %u\n",
+			   ec->rx_max_coalesced_frames_irq,
+			   cdev->mcfg[MRAM_RXF0].num);
+		return -EINVAL;
+	}
+	if ((ec->rx_max_coalesced_frames_irq == 0) != (ec->rx_coalesce_usecs_irq == 0)) {
+		netdev_err(dev, "rx-frames-irq and rx-usecs-irq can only be set together\n");
+		return -EINVAL;
+	}
+	if (ec->tx_max_coalesced_frames_irq > cdev->mcfg[MRAM_TXE].num) {
+		netdev_err(dev, "tx-frames-irq %u greater than the TX event FIFO %u\n",
+			   ec->tx_max_coalesced_frames_irq,
+			   cdev->mcfg[MRAM_TXE].num);
+		return -EINVAL;
+	}
+	if (ec->tx_max_coalesced_frames_irq > cdev->mcfg[MRAM_TXB].num) {
+		netdev_err(dev, "tx-frames-irq %u greater than the TX FIFO %u\n",
+			   ec->tx_max_coalesced_frames_irq,
+			   cdev->mcfg[MRAM_TXB].num);
+		return -EINVAL;
+	}
+	if ((ec->tx_max_coalesced_frames_irq == 0) != (ec->tx_coalesce_usecs_irq == 0)) {
+		netdev_err(dev, "tx-frames-irq and tx-usecs-irq can only be set together\n");
+		return -EINVAL;
+	}
+	if (ec->tx_max_coalesced_frames > cdev->mcfg[MRAM_TXE].num) {
+		netdev_err(dev, "tx-frames %u greater than the TX event FIFO %u\n",
+			   ec->tx_max_coalesced_frames,
+			   cdev->mcfg[MRAM_TXE].num);
+		return -EINVAL;
+	}
+	if (ec->tx_max_coalesced_frames > cdev->mcfg[MRAM_TXB].num) {
+		netdev_err(dev, "tx-frames %u greater than the TX FIFO %u\n",
+			   ec->tx_max_coalesced_frames,
+			   cdev->mcfg[MRAM_TXB].num);
+		return -EINVAL;
+	}
+	if (ec->rx_coalesce_usecs_irq != 0 && ec->tx_coalesce_usecs_irq != 0 &&
+	    ec->rx_coalesce_usecs_irq != ec->tx_coalesce_usecs_irq) {
+		netdev_err(dev, "rx-usecs-irq %u needs to be equal to tx-usecs-irq %u if both are enabled\n",
+			   ec->rx_coalesce_usecs_irq,
+			   ec->tx_coalesce_usecs_irq);
+		return -EINVAL;
+	}
+
+	cdev->rx_max_coalesced_frames_irq = ec->rx_max_coalesced_frames_irq;
+	cdev->rx_coalesce_usecs_irq = ec->rx_coalesce_usecs_irq;
+	cdev->tx_max_coalesced_frames = ec->tx_max_coalesced_frames;
+	cdev->tx_max_coalesced_frames_irq = ec->tx_max_coalesced_frames_irq;
+	cdev->tx_coalesce_usecs_irq = ec->tx_coalesce_usecs_irq;
+
+	if (cdev->rx_coalesce_usecs_irq)
+		cdev->irq_timer_wait =
+			ns_to_ktime(cdev->rx_coalesce_usecs_irq * NSEC_PER_USEC);
+	else
+		cdev->irq_timer_wait =
+			ns_to_ktime(cdev->tx_coalesce_usecs_irq * NSEC_PER_USEC);
+
+	return 0;
+}
+
 static const struct ethtool_ops m_can_ethtool_ops = {
+	.supported_coalesce_params = ETHTOOL_COALESCE_RX_USECS_IRQ |
+		ETHTOOL_COALESCE_RX_MAX_FRAMES_IRQ |
+		ETHTOOL_COALESCE_TX_USECS_IRQ |
+		ETHTOOL_COALESCE_TX_MAX_FRAMES |
+		ETHTOOL_COALESCE_TX_MAX_FRAMES_IRQ,
+	.get_ts_info = ethtool_op_get_ts_info,
+	.get_coalesce = m_can_get_coalesce,
+	.set_coalesce = m_can_set_coalesce,
+};
+
+static const struct ethtool_ops m_can_ethtool_ops_polling = {
 	.get_ts_info = ethtool_op_get_ts_info,
 };
 
@@ -1908,7 +2148,10 @@ static int register_m_can_dev(struct net_device *dev)
 {
 	dev->flags |= IFF_ECHO;	/* we support local echo */
 	dev->netdev_ops = &m_can_netdev_ops;
-	dev->ethtool_ops = &m_can_ethtool_ops;
+	if (dev->irq)
+		dev->ethtool_ops = &m_can_ethtool_ops;
+	else
+		dev->ethtool_ops = &m_can_ethtool_ops_polling;
 
 	return register_candev(dev);
 }
@@ -2056,6 +2299,19 @@ int m_can_class_register(struct m_can_classdev *cdev)
 {
 	int ret;
 
+	cdev->tx_fifo_size = max(1, min(cdev->mcfg[MRAM_TXB].num,
+					cdev->mcfg[MRAM_TXE].num));
+	if (cdev->is_peripheral) {
+		cdev->tx_ops =
+			devm_kzalloc(cdev->dev,
+				     cdev->tx_fifo_size * sizeof(*cdev->tx_ops),
+				     GFP_KERNEL);
+		if (!cdev->tx_ops) {
+			dev_err(cdev->dev, "Failed to allocate tx_ops for workqueue\n");
+			return -ENOMEM;
+		}
+	}
+
 	if (cdev->pm_clock_support) {
 		ret = m_can_clk_start(cdev);
 		if (ret)
@@ -2069,8 +2325,15 @@ int m_can_class_register(struct m_can_classdev *cdev)
 			goto clk_disable;
 	}
 
-	if (!cdev->net->irq)
+	if (!cdev->net->irq) {
+		dev_dbg(cdev->dev, "Polling enabled, initialize hrtimer");
+		hrtimer_init(&cdev->hrtimer, CLOCK_MONOTONIC,
+			     HRTIMER_MODE_REL_PINNED);
 		cdev->hrtimer.function = &hrtimer_callback;
+	} else {
+		hrtimer_init(&cdev->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		cdev->hrtimer.function = m_can_coalescing_timer;
+	}
 
 	ret = m_can_dev_setup(cdev);
 	if (ret)

drivers/net/can/m_can/m_can.h

@@ -70,6 +70,13 @@ struct m_can_ops {
 	int (*init)(struct m_can_classdev *cdev);
 };
 
+struct m_can_tx_op {
+	struct m_can_classdev *cdev;
+	struct work_struct work;
+	struct sk_buff *skb;
+	bool submit;
+};
+
 struct m_can_classdev {
 	struct can_priv can;
 	struct can_rx_offload offload;
@@ -80,10 +87,10 @@ struct m_can_classdev {
 	struct clk *cclk;
 
 	struct workqueue_struct *tx_wq;
-	struct work_struct tx_work;
-	struct sk_buff *tx_skb;
 	struct phy *transceiver;
 
+	ktime_t irq_timer_wait;
+
 	struct m_can_ops *ops;
 
 	int version;
@@ -92,6 +99,29 @@ struct m_can_classdev {
 	int pm_clock_support;
 	int is_peripheral;
 
+	// Cached M_CAN_IE register content
+	u32 active_interrupts;
+	u32 rx_max_coalesced_frames_irq;
+	u32 rx_coalesce_usecs_irq;
+	u32 tx_max_coalesced_frames;
+	u32 tx_max_coalesced_frames_irq;
+	u32 tx_coalesce_usecs_irq;
+
+	// Store this internally to avoid fetch delays on peripheral chips
+	u32 tx_fifo_putidx;
+
+	/* Protects shared state between start_xmit and m_can_isr */
+	spinlock_t tx_handling_spinlock;
+	int tx_fifo_in_flight;
+
+	struct m_can_tx_op *tx_ops;
+	int tx_fifo_size;
+	int next_tx_op;
+
+	int nr_txs_without_submit;
+	/* bitfield of fifo elements that will be submitted together */
+	u32 tx_peripheral_submit;
+
 	struct mram_cfg mcfg[MRAM_CFG_NUM];
 
 	struct hrtimer hrtimer;

drivers/net/can/m_can/m_can_platform.c

@@ -109,10 +109,6 @@ static int m_can_plat_probe(struct platform_device *pdev)
 			ret = irq;
 			goto probe_fail;
 		}
-	} else {
-		dev_dbg(mcan_class->dev, "Polling enabled, initialize hrtimer");
-		hrtimer_init(&mcan_class->hrtimer, CLOCK_MONOTONIC,
-			     HRTIMER_MODE_REL_PINNED);
 	}
 
 	/* message ram could be shared */

drivers/net/can/softing/softing_fw.c

@@ -436,7 +436,7 @@ int softing_startstop(struct net_device *dev, int up)
 		return ret;
 
 	bus_bitmask_start = 0;
-	if (dev && up)
+	if (up)
 		/* prepare to start this bus as well */
 		bus_bitmask_start |= (1 << priv->index);
 	/* bring netdevs down */

include/uapi/linux/can.h

@@ -193,9 +193,14 @@ struct canfd_frame {
 #define CANXL_XLF 0x80 /* mandatory CAN XL frame flag (must always be set!) */
 #define CANXL_SEC 0x01 /* Simple Extended Content (security/segmentation) */
 
+/* the 8-bit VCID is optionally placed in the canxl_frame.prio element */
+#define CANXL_VCID_OFFSET 16 /* bit offset of VCID in prio element */
+#define CANXL_VCID_VAL_MASK 0xFFUL /* VCID is an 8-bit value */
+#define CANXL_VCID_MASK (CANXL_VCID_VAL_MASK << CANXL_VCID_OFFSET)
+
 /**
  * struct canxl_frame - CAN with e'X'tended frame 'L'ength frame structure
- * @prio:  11 bit arbitration priority with zero'ed CAN_*_FLAG flags
+ * @prio:  11 bit arbitration priority with zero'ed CAN_*_FLAG flags / VCID
  * @flags: additional flags for CAN XL
  * @sdt:   SDU (service data unit) type
  * @len:   frame payload length in byte (CANXL_MIN_DLEN .. CANXL_MAX_DLEN)
@@ -205,7 +210,7 @@ struct canfd_frame {
  * @prio shares the same position as @can_id from struct can[fd]_frame.
  */
 struct canxl_frame {
-	canid_t prio;  /* 11 bit priority for arbitration (canid_t) */
+	canid_t prio;  /* 11 bit priority for arbitration / 8 bit VCID */
 	__u8    flags; /* additional flags for CAN XL */
 	__u8    sdt;   /* SDU (service data unit) type */
 	__u16   len;   /* frame payload length in byte */

include/uapi/linux/can/isotp.h

@@ -137,6 +137,7 @@ struct can_isotp_ll_options {
 #define CAN_ISOTP_WAIT_TX_DONE	0x0400	/* wait for tx completion */
 #define CAN_ISOTP_SF_BROADCAST	0x0800	/* 1-to-N functional addressing */
 #define CAN_ISOTP_CF_BROADCAST	0x1000	/* 1-to-N transmission w/o FC */
+#define CAN_ISOTP_DYN_FC_PARMS	0x2000	/* dynamic FC parameters BS/STmin */
 
 /* protocol machine default values */
 

include/uapi/linux/can/raw.h

@@ -65,6 +65,22 @@ enum {
 	CAN_RAW_FD_FRAMES,	/* allow CAN FD frames (default:off) */
 	CAN_RAW_JOIN_FILTERS,	/* all filters must match to trigger */
 	CAN_RAW_XL_FRAMES,	/* allow CAN XL frames (default:off) */
+	CAN_RAW_XL_VCID_OPTS,	/* CAN XL VCID configuration options */
 };
 
+/* configuration for CAN XL virtual CAN identifier (VCID) handling */
+struct can_raw_vcid_options {
+
+	__u8 flags;		/* flags for vcid (filter) behaviour */
+	__u8 tx_vcid;		/* VCID value set into canxl_frame.prio */
+	__u8 rx_vcid;		/* VCID value for VCID filter */
+	__u8 rx_vcid_mask;	/* VCID mask for VCID filter */
+
+};
+
+/* can_raw_vcid_options.flags for CAN XL virtual CAN identifier handling */
+#define CAN_RAW_XL_VCID_TX_SET		0x01
+#define CAN_RAW_XL_VCID_TX_PASS		0x02
+#define CAN_RAW_XL_VCID_RX_FILTER	0x04
+
 #endif /* !_UAPI_CAN_RAW_H */

net/can/af_can.c

@@ -865,6 +865,8 @@ static __init int can_init(void)
 	/* check for correct padding to be able to use the structs similarly */
 	BUILD_BUG_ON(offsetof(struct can_frame, len) !=
 		     offsetof(struct canfd_frame, len) ||
+		     offsetof(struct can_frame, len) !=
+		     offsetof(struct canxl_frame, flags) ||
 		     offsetof(struct can_frame, data) !=
 		     offsetof(struct canfd_frame, data));
 

net/can/bcm.c

@@ -72,9 +72,11 @@
 #define BCM_TIMER_SEC_MAX (400 * 24 * 60 * 60)
 
 /* use of last_frames[index].flags */
+#define RX_LOCAL   0x10 /* frame was created on the local host */
+#define RX_OWN     0x20 /* frame was sent via the socket it was received on */
 #define RX_RECV    0x40 /* received data for this element */
 #define RX_THR     0x80 /* element not been sent due to throttle feature */
-#define BCM_CAN_FLAGS_MASK 0x3F /* to clean private flags after usage */
+#define BCM_CAN_FLAGS_MASK 0x0F /* to clean private flags after usage */
 
 /* get best masking value for can_rx_register() for a given single can_id */
 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
@@ -138,6 +140,16 @@ static LIST_HEAD(bcm_notifier_list);
 static DEFINE_SPINLOCK(bcm_notifier_lock);
 static struct bcm_sock *bcm_busy_notifier;
 
+/* Return pointer to store the extra msg flags for bcm_recvmsg().
+ * We use the space of one unsigned int beyond the 'struct sockaddr_can'
+ * in skb->cb.
+ */
+static inline unsigned int *bcm_flags(struct sk_buff *skb)
+{
+	/* return pointer after struct sockaddr_can */
+	return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
+}
+
 static inline struct bcm_sock *bcm_sk(const struct sock *sk)
 {
 	return (struct bcm_sock *)sk;
@@ -325,6 +337,7 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
 	struct sock *sk = op->sk;
 	unsigned int datalen = head->nframes * op->cfsiz;
 	int err;
+	unsigned int *pflags;
 
 	skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
 	if (!skb)
@@ -332,6 +345,14 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
 
 	skb_put_data(skb, head, sizeof(*head));
 
+	/* ensure space for sockaddr_can and msg flags */
+	sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
+			       sizeof(unsigned int));
+
+	/* initialize msg flags */
+	pflags = bcm_flags(skb);
+	*pflags = 0;
+
 	if (head->nframes) {
 		/* CAN frames starting here */
 		firstframe = (struct canfd_frame *)skb_tail_pointer(skb);
@@ -344,8 +365,14 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
 		 * relevant for updates that are generated by the
 		 * BCM, where nframes is 1
 		 */
-		if (head->nframes == 1)
+		if (head->nframes == 1) {
+			if (firstframe->flags & RX_LOCAL)
+				*pflags |= MSG_DONTROUTE;
+			if (firstframe->flags & RX_OWN)
+				*pflags |= MSG_CONFIRM;
+
 			firstframe->flags &= BCM_CAN_FLAGS_MASK;
+		}
 	}
 
 	if (has_timestamp) {
@@ -360,7 +387,6 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
 	 *  containing the interface index.
 	 */
 
-	sock_skb_cb_check_size(sizeof(struct sockaddr_can));
 	addr = (struct sockaddr_can *)skb->cb;
 	memset(addr, 0, sizeof(*addr));
 	addr->can_family  = AF_CAN;
@@ -444,7 +470,7 @@ static void bcm_rx_changed(struct bcm_op *op, struct canfd_frame *data)
 		op->frames_filtered = op->frames_abs = 0;
 
 	/* this element is not throttled anymore */
-	data->flags &= (BCM_CAN_FLAGS_MASK|RX_RECV);
+	data->flags &= ~RX_THR;
 
 	memset(&head, 0, sizeof(head));
 	head.opcode  = RX_CHANGED;
@@ -465,13 +491,17 @@ static void bcm_rx_changed(struct bcm_op *op, struct canfd_frame *data)
  */
 static void bcm_rx_update_and_send(struct bcm_op *op,
 				   struct canfd_frame *lastdata,
-				   const struct canfd_frame *rxdata)
+				   const struct canfd_frame *rxdata,
+				   unsigned char traffic_flags)
 {
 	memcpy(lastdata, rxdata, op->cfsiz);
 
 	/* mark as used and throttled by default */
 	lastdata->flags |= (RX_RECV|RX_THR);
 
+	/* add own/local/remote traffic flags */
+	lastdata->flags |= traffic_flags;
+
 	/* throttling mode inactive ? */
 	if (!op->kt_ival2) {
 		/* send RX_CHANGED to the user immediately */
@@ -508,7 +538,8 @@ static void bcm_rx_update_and_send(struct bcm_op *op,
  *                       received data stored in op->last_frames[]
  */
 static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index,
-				const struct canfd_frame *rxdata)
+				const struct canfd_frame *rxdata,
+				unsigned char traffic_flags)
 {
 	struct canfd_frame *cf = op->frames + op->cfsiz * index;
 	struct canfd_frame *lcf = op->last_frames + op->cfsiz * index;
@@ -521,7 +552,7 @@ static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index,
 
 	if (!(lcf->flags & RX_RECV)) {
 		/* received data for the first time => send update to user */
-		bcm_rx_update_and_send(op, lcf, rxdata);
+		bcm_rx_update_and_send(op, lcf, rxdata, traffic_flags);
 		return;
 	}
 
@@ -529,7 +560,7 @@ static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index,
 	for (i = 0; i < rxdata->len; i += 8) {
 		if ((get_u64(cf, i) & get_u64(rxdata, i)) !=
 		    (get_u64(cf, i) & get_u64(lcf, i))) {
-			bcm_rx_update_and_send(op, lcf, rxdata);
+			bcm_rx_update_and_send(op, lcf, rxdata, traffic_flags);
 			return;
 		}
 	}
@@ -537,7 +568,7 @@ static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index,
 	if (op->flags & RX_CHECK_DLC) {
 		/* do a real check in CAN frame length */
 		if (rxdata->len != lcf->len) {
-			bcm_rx_update_and_send(op, lcf, rxdata);
+			bcm_rx_update_and_send(op, lcf, rxdata, traffic_flags);
 			return;
 		}
 	}
@@ -644,6 +675,7 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data)
 	struct bcm_op *op = (struct bcm_op *)data;
 	const struct canfd_frame *rxframe = (struct canfd_frame *)skb->data;
 	unsigned int i;
+	unsigned char traffic_flags;
 
 	if (op->can_id != rxframe->can_id)
 		return;
@@ -673,15 +705,24 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data)
 		return;
 	}
 
+	/* compute flags to distinguish between own/local/remote CAN traffic */
+	traffic_flags = 0;
+	if (skb->sk) {
+		traffic_flags |= RX_LOCAL;
+		if (skb->sk == op->sk)
+			traffic_flags |= RX_OWN;
+	}
+
 	if (op->flags & RX_FILTER_ID) {
 		/* the easiest case */
-		bcm_rx_update_and_send(op, op->last_frames, rxframe);
+		bcm_rx_update_and_send(op, op->last_frames, rxframe,
+				       traffic_flags);
 		goto rx_starttimer;
 	}
 
 	if (op->nframes == 1) {
 		/* simple compare with index 0 */
-		bcm_rx_cmp_to_index(op, 0, rxframe);
+		bcm_rx_cmp_to_index(op, 0, rxframe, traffic_flags);
 		goto rx_starttimer;
 	}
 
@@ -698,7 +739,8 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data)
 			if ((get_u64(op->frames, 0) & get_u64(rxframe, 0)) ==
 			    (get_u64(op->frames, 0) &
 			     get_u64(op->frames + op->cfsiz * i, 0))) {
-				bcm_rx_cmp_to_index(op, i, rxframe);
+				bcm_rx_cmp_to_index(op, i, rxframe,
+						    traffic_flags);
 				break;
 			}
 		}
@@ -1675,6 +1717,9 @@ static int bcm_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 		memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
 	}
 
+	/* assign the flags that have been recorded in bcm_send_to_user() */
+	msg->msg_flags |= *(bcm_flags(skb));
+
 	skb_free_datagram(sk, skb);
 
 	return size;

net/can/isotp.c

@@ -381,8 +381,9 @@ static int isotp_rcv_fc(struct isotp_sock *so, struct canfd_frame *cf, int ae)
 		return 1;
 	}
 
-	/* get communication parameters only from the first FC frame */
-	if (so->tx.state == ISOTP_WAIT_FIRST_FC) {
+	/* get static/dynamic communication params from first/every FC frame */
+	if (so->tx.state == ISOTP_WAIT_FIRST_FC ||
+	    so->opt.flags & CAN_ISOTP_DYN_FC_PARMS) {
 		so->txfc.bs = cf->data[ae + 1];
 		so->txfc.stmin = cf->data[ae + 2];
 

net/can/raw.c

@@ -91,6 +91,10 @@ struct raw_sock {
 	int recv_own_msgs;
 	int fd_frames;
 	int xl_frames;
+	struct can_raw_vcid_options raw_vcid_opts;
+	canid_t tx_vcid_shifted;
+	canid_t rx_vcid_shifted;
+	canid_t rx_vcid_mask_shifted;
 	int join_filters;
 	int count;                 /* number of active filters */
 	struct can_filter dfilter; /* default/single filter */
@@ -134,10 +138,29 @@ static void raw_rcv(struct sk_buff *oskb, void *data)
 		return;
 
 	/* make sure to not pass oversized frames to the socket */
-	if ((!ro->fd_frames && can_is_canfd_skb(oskb)) ||
-	    (!ro->xl_frames && can_is_canxl_skb(oskb)))
+	if (!ro->fd_frames && can_is_canfd_skb(oskb))
 		return;
 
+	if (can_is_canxl_skb(oskb)) {
+		struct canxl_frame *cxl = (struct canxl_frame *)oskb->data;
+
+		/* make sure to not pass oversized frames to the socket */
+		if (!ro->xl_frames)
+			return;
+
+		/* filter CAN XL VCID content */
+		if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_RX_FILTER) {
+			/* apply VCID filter if user enabled the filter */
+			if ((cxl->prio & ro->rx_vcid_mask_shifted) !=
+			    (ro->rx_vcid_shifted & ro->rx_vcid_mask_shifted))
+				return;
+		} else {
+			/* no filter => do not forward VCID tagged frames */
+			if (cxl->prio & CANXL_VCID_MASK)
+				return;
+		}
+	}
+
 	/* eliminate multiple filter matches for the same skb */
 	if (this_cpu_ptr(ro->uniq)->skb == oskb &&
 	    this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
@@ -698,6 +721,19 @@ static int raw_setsockopt(struct socket *sock, int level, int optname,
 			ro->fd_frames = ro->xl_frames;
 		break;
 
+	case CAN_RAW_XL_VCID_OPTS:
+		if (optlen != sizeof(ro->raw_vcid_opts))
+			return -EINVAL;
+
+		if (copy_from_sockptr(&ro->raw_vcid_opts, optval, optlen))
+			return -EFAULT;
+
+		/* prepare 32 bit values for handling in hot path */
+		ro->tx_vcid_shifted = ro->raw_vcid_opts.tx_vcid << CANXL_VCID_OFFSET;
+		ro->rx_vcid_shifted = ro->raw_vcid_opts.rx_vcid << CANXL_VCID_OFFSET;
+		ro->rx_vcid_mask_shifted = ro->raw_vcid_opts.rx_vcid_mask << CANXL_VCID_OFFSET;
+		break;
+
 	case CAN_RAW_JOIN_FILTERS:
 		if (optlen != sizeof(ro->join_filters))
 			return -EINVAL;
@@ -786,6 +822,21 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
 		val = &ro->xl_frames;
 		break;
 
+	case CAN_RAW_XL_VCID_OPTS:
+		/* user space buffer to small for VCID opts? */
+		if (len < sizeof(ro->raw_vcid_opts)) {
+			/* return -ERANGE and needed space in optlen */
+			err = -ERANGE;
+			if (put_user(sizeof(ro->raw_vcid_opts), optlen))
+				err = -EFAULT;
+		} else {
+			if (len > sizeof(ro->raw_vcid_opts))
+				len = sizeof(ro->raw_vcid_opts);
+			if (copy_to_user(optval, &ro->raw_vcid_opts, len))
+				err = -EFAULT;
+		}
+		break;
+
 	case CAN_RAW_JOIN_FILTERS:
 		if (len > sizeof(int))
 			len = sizeof(int);
@@ -803,23 +854,41 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
 	return 0;
 }
 
-static bool raw_bad_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu)
+static void raw_put_canxl_vcid(struct raw_sock *ro, struct sk_buff *skb)
+{
+	struct canxl_frame *cxl = (struct canxl_frame *)skb->data;
+
+	/* sanitize non CAN XL bits */
+	cxl->prio &= (CANXL_PRIO_MASK | CANXL_VCID_MASK);
+
+	/* clear VCID in CAN XL frame if pass through is disabled */
+	if (!(ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_PASS))
+		cxl->prio &= CANXL_PRIO_MASK;
+
+	/* set VCID in CAN XL frame if enabled */
+	if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_SET) {
+		cxl->prio &= CANXL_PRIO_MASK;
+		cxl->prio |= ro->tx_vcid_shifted;
+	}
+}
+
+static unsigned int raw_check_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu)
 {
 	/* Classical CAN -> no checks for flags and device capabilities */
 	if (can_is_can_skb(skb))
-		return false;
+		return CAN_MTU;
 
 	/* CAN FD -> needs to be enabled and a CAN FD or CAN XL device */
 	if (ro->fd_frames && can_is_canfd_skb(skb) &&
 	    (mtu == CANFD_MTU || can_is_canxl_dev_mtu(mtu)))
-		return false;
+		return CANFD_MTU;
 
 	/* CAN XL -> needs to be enabled and a CAN XL device */
 	if (ro->xl_frames && can_is_canxl_skb(skb) &&
 	    can_is_canxl_dev_mtu(mtu))
-		return false;
+		return CANXL_MTU;
 
-	return true;
+	return 0;
 }
 
 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
@@ -829,6 +898,7 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	struct sockcm_cookie sockc;
 	struct sk_buff *skb;
 	struct net_device *dev;
+	unsigned int txmtu;
 	int ifindex;
 	int err = -EINVAL;
 
@@ -869,9 +939,16 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 		goto free_skb;
 
 	err = -EINVAL;
-	if (raw_bad_txframe(ro, skb, dev->mtu))
+
+	/* check for valid CAN (CC/FD/XL) frame content */
+	txmtu = raw_check_txframe(ro, skb, dev->mtu);
+	if (!txmtu)
 		goto free_skb;
 
+	/* only CANXL: clear/forward/set VCID value */
+	if (txmtu == CANXL_MTU)
+		raw_put_canxl_vcid(ro, skb);
+
 	sockcm_init(&sockc, sk);
 	if (msg->msg_controllen) {
 		err = sock_cmsg_send(sk, msg, &sockc);