Commit afa17a50 authored by Wolfram Sang's avatar Wolfram Sang Committed by David S. Miller

net/can: add driver for mscan family & mpc52xx_mscan

Taken from socketcan-svn, fixed remaining todos, cleaned up, tested with a
phyCORE-MPC5200B-IO and a custom board.
Signed-off-by: default avatarWolfram Sang <w.sang@pengutronix.de>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 88880135
......@@ -178,3 +178,12 @@ External interrupts:
external irq3: interrupts = <1 3 n>;
'n' is sense (0: level high, 1: edge rising, 2: edge falling 3: level low)
fsl,mpc5200-mscan nodes
-----------------------
In addition to the required compatible-, reg- and interrupt-properites, you can
also specify which clock shall be used for the bus:
- fsl,mscan-clk-src - a string describing the clock source. Valid values
are "ip" for IP_CLK and "sys" for SYS_XTAL.
"sys" is the default in case the property is not
present.
......@@ -108,6 +108,25 @@ config CAN_MCP251X
---help---
Driver for the Microchip MCP251x SPI CAN controllers.
config CAN_MSCAN
depends on CAN_DEV && (PPC || M68K || M68KNOMMU)
tristate "Support for Freescale MSCAN based chips"
---help---
The Motorola Scalable Controller Area Network (MSCAN) definition
is based on the MSCAN12 definition which is the specific
implementation of the Motorola Scalable CAN concept targeted for
the Motorola MC68HC12 Microcontroller Family.
config CAN_MPC52XX
tristate "Freescale MPC5xxx onboard CAN controller"
depends on CAN_MSCAN && PPC_MPC52xx
---help---
If you say yes here you get support for Freescale's MPC52xx
onboard dualCAN controller.
This driver can also be built as a module. If so, the module
will be called mpc5xxx_can.
config CAN_DEBUG_DEVICES
bool "CAN devices debugging messages"
depends on CAN
......
......@@ -10,6 +10,7 @@ can-dev-y := dev.o
obj-y += usb/
obj-$(CONFIG_CAN_SJA1000) += sja1000/
obj-$(CONFIG_CAN_MSCAN) += mscan/
obj-$(CONFIG_CAN_AT91) += at91_can.o
obj-$(CONFIG_CAN_TI_HECC) += ti_hecc.o
obj-$(CONFIG_CAN_MCP251X) += mcp251x.o
......
obj-$(CONFIG_CAN_MPC52XX) += mscan-mpc52xx.o
mscan-mpc52xx-objs := mscan.o mpc52xx_can.o
ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG
/*
* CAN bus driver for the Freescale MPC5xxx embedded CPU.
*
* Copyright (C) 2004-2005 Andrey Volkov <avolkov@varma-el.com>,
* Varma Electronics Oy
* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
* Copyright (C) 2009 Wolfram Sang, Pengutronix <w.sang@pengutronix.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the version 2 of the GNU General Public License
* as published by the Free Software Foundation
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/netdevice.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/of_platform.h>
#include <sysdev/fsl_soc.h>
#include <linux/io.h>
#include <asm/mpc52xx.h>
#include "mscan.h"
#define DRV_NAME "mpc5xxx_can"
static struct of_device_id mpc52xx_cdm_ids[] __devinitdata = {
{ .compatible = "fsl,mpc5200-cdm", },
{ .compatible = "fsl,mpc5200b-cdm", },
{}
};
/*
* Get the frequency of the external oscillator clock connected
* to the SYS_XTAL_IN pin, or return 0 if it cannot be determined.
*/
static unsigned int __devinit mpc52xx_can_xtal_freq(struct of_device *of)
{
struct mpc52xx_cdm __iomem *cdm;
struct device_node *np_cdm;
unsigned int freq;
u32 val;
freq = mpc5xxx_get_bus_frequency(of->node);
if (!freq)
return 0;
/*
* Determine SYS_XTAL_IN frequency from the clock domain settings
*/
np_cdm = of_find_matching_node(NULL, mpc52xx_cdm_ids);
if (!np_cdm) {
dev_err(&of->dev, "can't get clock node!\n");
return 0;
}
cdm = of_iomap(np_cdm, 0);
of_node_put(np_cdm);
if (in_8(&cdm->ipb_clk_sel) & 0x1)
freq *= 2;
val = in_be32(&cdm->rstcfg);
if (val & (1 << 5))
freq *= 8;
else
freq *= 4;
if (val & (1 << 6))
freq /= 12;
else
freq /= 16;
iounmap(cdm);
return freq;
}
/*
* Get frequency of the MSCAN clock source
*
* Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock (IP_CLK)
* can be selected. According to the MPC5200 user's manual, the oscillator
* clock is the better choice as it has less jitter but due to a hardware
* bug, it can not be selected for the old MPC5200 Rev. A chips.
*/
static unsigned int __devinit mpc52xx_can_clock_freq(struct of_device *of,
int clock_src)
{
unsigned int pvr;
pvr = mfspr(SPRN_PVR);
if (clock_src == MSCAN_CLKSRC_BUS || pvr == 0x80822011)
return mpc5xxx_get_bus_frequency(of->node);
return mpc52xx_can_xtal_freq(of);
}
static int __devinit mpc5xxx_can_probe(struct of_device *ofdev,
const struct of_device_id *id)
{
struct device_node *np = ofdev->node;
struct net_device *dev;
struct mscan_priv *priv;
void __iomem *base;
const char *clk_src;
int err, irq, clock_src;
base = of_iomap(ofdev->node, 0);
if (!base) {
dev_err(&ofdev->dev, "couldn't ioremap\n");
err = -ENOMEM;
goto exit_release_mem;
}
irq = irq_of_parse_and_map(np, 0);
if (!irq) {
dev_err(&ofdev->dev, "no irq found\n");
err = -ENODEV;
goto exit_unmap_mem;
}
dev = alloc_mscandev();
if (!dev) {
err = -ENOMEM;
goto exit_dispose_irq;
}
priv = netdev_priv(dev);
priv->reg_base = base;
dev->irq = irq;
/*
* Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock
* (IP_CLK) can be selected as MSCAN clock source. According to
* the MPC5200 user's manual, the oscillator clock is the better
* choice as it has less jitter. For this reason, it is selected
* by default.
*/
clk_src = of_get_property(np, "fsl,mscan-clk-src", NULL);
if (clk_src && strcmp(clk_src, "ip") == 0)
clock_src = MSCAN_CLKSRC_BUS;
else
clock_src = MSCAN_CLKSRC_XTAL;
priv->can.clock.freq = mpc52xx_can_clock_freq(ofdev, clock_src);
if (!priv->can.clock.freq) {
dev_err(&ofdev->dev, "couldn't get MSCAN clock frequency\n");
err = -ENODEV;
goto exit_free_mscan;
}
SET_NETDEV_DEV(dev, &ofdev->dev);
err = register_mscandev(dev, clock_src);
if (err) {
dev_err(&ofdev->dev, "registering %s failed (err=%d)\n",
DRV_NAME, err);
goto exit_free_mscan;
}
dev_set_drvdata(&ofdev->dev, dev);
dev_info(&ofdev->dev, "MSCAN at 0x%p, irq %d, clock %d Hz\n",
priv->reg_base, dev->irq, priv->can.clock.freq);
return 0;
exit_free_mscan:
free_candev(dev);
exit_dispose_irq:
irq_dispose_mapping(irq);
exit_unmap_mem:
iounmap(base);
exit_release_mem:
return err;
}
static int __devexit mpc5xxx_can_remove(struct of_device *ofdev)
{
struct net_device *dev = dev_get_drvdata(&ofdev->dev);
struct mscan_priv *priv = netdev_priv(dev);
dev_set_drvdata(&ofdev->dev, NULL);
unregister_mscandev(dev);
iounmap(priv->reg_base);
irq_dispose_mapping(dev->irq);
free_candev(dev);
return 0;
}
#ifdef CONFIG_PM
static struct mscan_regs saved_regs;
static int mpc5xxx_can_suspend(struct of_device *ofdev, pm_message_t state)
{
struct net_device *dev = dev_get_drvdata(&ofdev->dev);
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
_memcpy_fromio(&saved_regs, regs, sizeof(*regs));
return 0;
}
static int mpc5xxx_can_resume(struct of_device *ofdev)
{
struct net_device *dev = dev_get_drvdata(&ofdev->dev);
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
regs->canctl0 |= MSCAN_INITRQ;
while ((regs->canctl1 & MSCAN_INITAK) == 0)
udelay(10);
regs->canctl1 = saved_regs.canctl1;
regs->canbtr0 = saved_regs.canbtr0;
regs->canbtr1 = saved_regs.canbtr1;
regs->canidac = saved_regs.canidac;
/* restore masks, buffers etc. */
_memcpy_toio(&regs->canidar1_0, (void *)&saved_regs.canidar1_0,
sizeof(*regs) - offsetof(struct mscan_regs, canidar1_0));
regs->canctl0 &= ~MSCAN_INITRQ;
regs->cantbsel = saved_regs.cantbsel;
regs->canrier = saved_regs.canrier;
regs->cantier = saved_regs.cantier;
regs->canctl0 = saved_regs.canctl0;
return 0;
}
#endif
static struct of_device_id __devinitdata mpc5xxx_can_table[] = {
{.compatible = "fsl,mpc5200-mscan"},
{.compatible = "fsl,mpc5200b-mscan"},
{},
};
static struct of_platform_driver mpc5xxx_can_driver = {
.owner = THIS_MODULE,
.name = "mpc5xxx_can",
.probe = mpc5xxx_can_probe,
.remove = __devexit_p(mpc5xxx_can_remove),
#ifdef CONFIG_PM
.suspend = mpc5xxx_can_suspend,
.resume = mpc5xxx_can_resume,
#endif
.match_table = mpc5xxx_can_table,
};
static int __init mpc5xxx_can_init(void)
{
return of_register_platform_driver(&mpc5xxx_can_driver);
}
module_init(mpc5xxx_can_init);
static void __exit mpc5xxx_can_exit(void)
{
return of_unregister_platform_driver(&mpc5xxx_can_driver);
};
module_exit(mpc5xxx_can_exit);
MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
MODULE_DESCRIPTION("Freescale MPC5200 CAN driver");
MODULE_LICENSE("GPL v2");
/*
* CAN bus driver for the alone generic (as possible as) MSCAN controller.
*
* Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>,
* Varma Electronics Oy
* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
* Copytight (C) 2008-2009 Pengutronix <kernel@pengutronix.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the version 2 of the GNU General Public License
* as published by the Free Software Foundation
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/list.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/error.h>
#include <linux/io.h>
#include "mscan.h"
#define MSCAN_NORMAL_MODE 0
#define MSCAN_SLEEP_MODE MSCAN_SLPRQ
#define MSCAN_INIT_MODE (MSCAN_INITRQ | MSCAN_SLPRQ)
#define MSCAN_POWEROFF_MODE (MSCAN_CSWAI | MSCAN_SLPRQ)
#define MSCAN_SET_MODE_RETRIES 255
#define MSCAN_ECHO_SKB_MAX 3
#define BTR0_BRP_MASK 0x3f
#define BTR0_SJW_SHIFT 6
#define BTR0_SJW_MASK (0x3 << BTR0_SJW_SHIFT)
#define BTR1_TSEG1_MASK 0xf
#define BTR1_TSEG2_SHIFT 4
#define BTR1_TSEG2_MASK (0x7 << BTR1_TSEG2_SHIFT)
#define BTR1_SAM_SHIFT 7
#define BTR0_SET_BRP(brp) (((brp) - 1) & BTR0_BRP_MASK)
#define BTR0_SET_SJW(sjw) ((((sjw) - 1) << BTR0_SJW_SHIFT) & \
BTR0_SJW_MASK)
#define BTR1_SET_TSEG1(tseg1) (((tseg1) - 1) & BTR1_TSEG1_MASK)
#define BTR1_SET_TSEG2(tseg2) ((((tseg2) - 1) << BTR1_TSEG2_SHIFT) & \
BTR1_TSEG2_MASK)
#define BTR1_SET_SAM(sam) ((sam) ? 1 << BTR1_SAM_SHIFT : 0)
static struct can_bittiming_const mscan_bittiming_const = {
.name = "mscan",
.tseg1_min = 4,
.tseg1_max = 16,
.tseg2_min = 2,
.tseg2_max = 8,
.sjw_max = 4,
.brp_min = 1,
.brp_max = 64,
.brp_inc = 1,
};
struct mscan_state {
u8 mode;
u8 canrier;
u8 cantier;
};
#define F_RX_PROGRESS 0
#define F_TX_PROGRESS 1
#define F_TX_WAIT_ALL 2
static enum can_state state_map[] = {
CAN_STATE_ERROR_ACTIVE,
CAN_STATE_ERROR_WARNING,
CAN_STATE_ERROR_PASSIVE,
CAN_STATE_BUS_OFF
};
static int mscan_set_mode(struct net_device *dev, u8 mode)
{
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
int ret = 0;
int i;
u8 canctl1;
if (mode != MSCAN_NORMAL_MODE) {
if (priv->tx_active) {
/* Abort transfers before going to sleep */#
out_8(&regs->cantarq, priv->tx_active);
/* Suppress TX done interrupts */
out_8(&regs->cantier, 0);
}
canctl1 = in_8(&regs->canctl1);
if ((mode & MSCAN_SLPRQ) && (canctl1 & MSCAN_SLPAK) == 0) {
out_8(&regs->canctl0,
in_8(&regs->canctl0) | MSCAN_SLPRQ);
for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
if (in_8(&regs->canctl1) & MSCAN_SLPAK)
break;
udelay(100);
}
/*
* The mscan controller will fail to enter sleep mode,
* while there are irregular activities on bus, like
* somebody keeps retransmitting. This behavior is
* undocumented and seems to differ between mscan built
* in mpc5200b and mpc5200. We proceed in that case,
* since otherwise the slprq will be kept set and the
* controller will get stuck. NOTE: INITRQ or CSWAI
* will abort all active transmit actions, if still
* any, at once.
*/
if (i >= MSCAN_SET_MODE_RETRIES)
dev_dbg(dev->dev.parent,
"device failed to enter sleep mode. "
"We proceed anyhow.\n");
else
priv->can.state = CAN_STATE_SLEEPING;
}
if ((mode & MSCAN_INITRQ) && (canctl1 & MSCAN_INITAK) == 0) {
out_8(&regs->canctl0,
in_8(&regs->canctl0) | MSCAN_INITRQ);
for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
if (in_8(&regs->canctl1) & MSCAN_INITAK)
break;
}
if (i >= MSCAN_SET_MODE_RETRIES)
ret = -ENODEV;
}
if (!ret)
priv->can.state = CAN_STATE_STOPPED;
if (mode & MSCAN_CSWAI)
out_8(&regs->canctl0,
in_8(&regs->canctl0) | MSCAN_CSWAI);
} else {
canctl1 = in_8(&regs->canctl1);
if (canctl1 & (MSCAN_SLPAK | MSCAN_INITAK)) {
out_8(&regs->canctl0, in_8(&regs->canctl0) &
~(MSCAN_SLPRQ | MSCAN_INITRQ));
for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
canctl1 = in_8(&regs->canctl1);
if (!(canctl1 & (MSCAN_INITAK | MSCAN_SLPAK)))
break;
}
if (i >= MSCAN_SET_MODE_RETRIES)
ret = -ENODEV;
else
priv->can.state = CAN_STATE_ERROR_ACTIVE;
}
}
return ret;
}
static int mscan_start(struct net_device *dev)
{
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
u8 canrflg;
int err;
out_8(&regs->canrier, 0);
INIT_LIST_HEAD(&priv->tx_head);
priv->prev_buf_id = 0;
priv->cur_pri = 0;
priv->tx_active = 0;
priv->shadow_canrier = 0;
priv->flags = 0;
err = mscan_set_mode(dev, MSCAN_NORMAL_MODE);
if (err)
return err;
canrflg = in_8(&regs->canrflg);
priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;
priv->can.state = state_map[max(MSCAN_STATE_RX(canrflg),
MSCAN_STATE_TX(canrflg))];
out_8(&regs->cantier, 0);
/* Enable receive interrupts. */
out_8(&regs->canrier, MSCAN_OVRIE | MSCAN_RXFIE | MSCAN_CSCIE |
MSCAN_RSTATE1 | MSCAN_RSTATE0 | MSCAN_TSTATE1 | MSCAN_TSTATE0);
return 0;
}
static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct can_frame *frame = (struct can_frame *)skb->data;
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
int i, rtr, buf_id;
u32 can_id;
if (frame->can_dlc > 8)
return -EINVAL;
out_8(&regs->cantier, 0);
i = ~priv->tx_active & MSCAN_TXE;
buf_id = ffs(i) - 1;
switch (hweight8(i)) {
case 0:
netif_stop_queue(dev);
dev_err(dev->dev.parent, "Tx Ring full when queue awake!\n");
return NETDEV_TX_BUSY;
case 1:
/*
* if buf_id < 3, then current frame will be send out of order,
* since buffer with lower id have higher priority (hell..)
*/
netif_stop_queue(dev);
case 2:
if (buf_id < priv->prev_buf_id) {
priv->cur_pri++;
if (priv->cur_pri == 0xff) {
set_bit(F_TX_WAIT_ALL, &priv->flags);
netif_stop_queue(dev);
}
}
set_bit(F_TX_PROGRESS, &priv->flags);
break;
}
priv->prev_buf_id = buf_id;
out_8(&regs->cantbsel, i);
rtr = frame->can_id & CAN_RTR_FLAG;
if (frame->can_id & CAN_EFF_FLAG) {
can_id = (frame->can_id & CAN_EFF_MASK) << 1;
if (rtr)
can_id |= 1;
out_be16(&regs->tx.idr3_2, can_id);
can_id >>= 16;
can_id = (can_id & 0x7) | ((can_id << 2) & 0xffe0) | (3 << 3);
} else {
can_id = (frame->can_id & CAN_SFF_MASK) << 5;
if (rtr)
can_id |= 1 << 4;
}
out_be16(&regs->tx.idr1_0, can_id);
if (!rtr) {
void __iomem *data = &regs->tx.dsr1_0;
u16 *payload = (u16 *) frame->data;
/* It is safe to write into dsr[dlc+1] */
for (i = 0; i < (frame->can_dlc + 1) / 2; i++) {
out_be16(data, *payload++);
data += 2 + _MSCAN_RESERVED_DSR_SIZE;
}
}
out_8(&regs->tx.dlr, frame->can_dlc);
out_8(&regs->tx.tbpr, priv->cur_pri);
/* Start transmission. */
out_8(&regs->cantflg, 1 << buf_id);
if (!test_bit(F_TX_PROGRESS, &priv->flags))
dev->trans_start = jiffies;
list_add_tail(&priv->tx_queue[buf_id].list, &priv->tx_head);
can_put_echo_skb(skb, dev, buf_id);
/* Enable interrupt. */
priv->tx_active |= 1 << buf_id;
out_8(&regs->cantier, priv->tx_active);
return NETDEV_TX_OK;
}
/* This function returns the old state to see where we came from */
static enum can_state check_set_state(struct net_device *dev, u8 canrflg)
{
struct mscan_priv *priv = netdev_priv(dev);
enum can_state state, old_state = priv->can.state;
if (canrflg & MSCAN_CSCIF && old_state <= CAN_STATE_BUS_OFF) {
state = state_map[max(MSCAN_STATE_RX(canrflg),
MSCAN_STATE_TX(canrflg))];
priv->can.state = state;
}
return old_state;
}
static void mscan_get_rx_frame(struct net_device *dev, struct can_frame *frame)
{
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
u32 can_id;
int i;
can_id = in_be16(&regs->rx.idr1_0);
if (can_id & (1 << 3)) {
frame->can_id = CAN_EFF_FLAG;
can_id = ((can_id << 16) | in_be16(&regs->rx.idr3_2));
can_id = ((can_id & 0xffe00000) |
((can_id & 0x7ffff) << 2)) >> 2;
} else {
can_id >>= 4;
frame->can_id = 0;
}
frame->can_id |= can_id >> 1;
if (can_id & 1)
frame->can_id |= CAN_RTR_FLAG;
frame->can_dlc = in_8(&regs->rx.dlr) & 0xf;
if (!(frame->can_id & CAN_RTR_FLAG)) {
void __iomem *data = &regs->rx.dsr1_0;
u16 *payload = (u16 *) frame->data;
for (i = 0; i < (frame->can_dlc + 1) / 2; i++) {
*payload++ = in_be16(data);
data += 2 + _MSCAN_RESERVED_DSR_SIZE;
}
}
out_8(&regs->canrflg, MSCAN_RXF);
}
static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame,
u8 canrflg)
{
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
struct net_device_stats *stats = &dev->stats;
enum can_state old_state;
dev_dbg(dev->dev.parent, "error interrupt (canrflg=%#x)\n", canrflg);
frame->can_id = CAN_ERR_FLAG;
if (canrflg & MSCAN_OVRIF) {
frame->can_id |= CAN_ERR_CRTL;
frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
stats->rx_over_errors++;
stats->rx_errors++;
} else
frame->data[1] = 0;
old_state = check_set_state(dev, canrflg);
/* State changed */
if (old_state != priv->can.state) {
switch (priv->can.state) {
case CAN_STATE_ERROR_WARNING:
frame->can_id |= CAN_ERR_CRTL;
priv->can.can_stats.error_warning++;
if ((priv->shadow_statflg & MSCAN_RSTAT_MSK) <
(canrflg & MSCAN_RSTAT_MSK))
frame->data[1] |= CAN_ERR_CRTL_RX_WARNING;
if ((priv->shadow_statflg & MSCAN_TSTAT_MSK) <
(canrflg & MSCAN_TSTAT_MSK))
frame->data[1] |= CAN_ERR_CRTL_TX_WARNING;
break;
case CAN_STATE_ERROR_PASSIVE:
frame->can_id |= CAN_ERR_CRTL;
priv->can.can_stats.error_passive++;
frame->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
break;
case CAN_STATE_BUS_OFF:
frame->can_id |= CAN_ERR_BUSOFF;
/*
* The MSCAN on the MPC5200 does recover from bus-off
* automatically. To avoid that we stop the chip doing
* a light-weight stop (we are in irq-context).
*/
out_8(&regs->cantier, 0);
out_8(&regs->canrier, 0);
out_8(&regs->canctl0, in_8(&regs->canctl0) |
MSCAN_SLPRQ | MSCAN_INITRQ);
can_bus_off(dev);
break;
default:
break;
}
}
priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;
frame->can_dlc = CAN_ERR_DLC;
out_8(&regs->canrflg, MSCAN_ERR_IF);
}
static int mscan_rx_poll(struct napi_struct *napi, int quota)
{
struct mscan_priv *priv = container_of(napi, struct mscan_priv, napi);
struct net_device *dev = napi->dev;
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
struct net_device_stats *stats = &dev->stats;
int npackets = 0;
int ret = 1;
struct sk_buff *skb;
struct can_frame *frame;
u8 canrflg;
while (npackets < quota && ((canrflg = in_8(&regs->canrflg)) &
(MSCAN_RXF | MSCAN_ERR_IF))) {
skb = alloc_can_skb(dev, &frame);
if (!skb) {
if (printk_ratelimit())
dev_notice(dev->dev.parent, "packet dropped\n");
stats->rx_dropped++;
out_8(&regs->canrflg, canrflg);
continue;
}
if (canrflg & MSCAN_RXF)
mscan_get_rx_frame(dev, frame);
else if (canrflg & MSCAN_ERR_IF)
mscan_get_err_frame(dev, frame, canrflg);
stats->rx_packets++;
stats->rx_bytes += frame->can_dlc;
npackets++;
netif_receive_skb(skb);
}
if (!(in_8(&regs->canrflg) & (MSCAN_RXF | MSCAN_ERR_IF))) {
napi_complete(&priv->napi);
clear_bit(F_RX_PROGRESS, &priv->flags);
if (priv->can.state < CAN_STATE_BUS_OFF)
out_8(&regs->canrier, priv->shadow_canrier);
ret = 0;
}
return ret;
}
static irqreturn_t mscan_isr(int irq, void *dev_id)
{
struct net_device *dev = (struct net_device *)dev_id;
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
struct net_device_stats *stats = &dev->stats;
u8 cantier, cantflg, canrflg;
irqreturn_t ret = IRQ_NONE;
cantier = in_8(&regs->cantier) & MSCAN_TXE;
cantflg = in_8(&regs->cantflg) & cantier;
if (cantier && cantflg) {
struct list_head *tmp, *pos;
list_for_each_safe(pos, tmp, &priv->tx_head) {
struct tx_queue_entry *entry =
list_entry(pos, struct tx_queue_entry, list);
u8 mask = entry->mask;
if (!(cantflg & mask))
continue;
out_8(&regs->cantbsel, mask);
stats->tx_bytes += in_8(&regs->tx.dlr);
stats->tx_packets++;
can_get_echo_skb(dev, entry->id);
priv->tx_active &= ~mask;
list_del(pos);
}
if (list_empty(&priv->tx_head)) {
clear_bit(F_TX_WAIT_ALL, &priv->flags);
clear_bit(F_TX_PROGRESS, &priv->flags);
priv->cur_pri = 0;
} else
dev->trans_start = jiffies;
if (!test_bit(F_TX_WAIT_ALL, &priv->flags))
netif_wake_queue(dev);
out_8(&regs->cantier, priv->tx_active);
ret = IRQ_HANDLED;
}
canrflg = in_8(&regs->canrflg);
if ((canrflg & ~MSCAN_STAT_MSK) &&
!test_and_set_bit(F_RX_PROGRESS, &priv->flags)) {
if (canrflg & ~MSCAN_STAT_MSK) {
priv->shadow_canrier = in_8(&regs->canrier);
out_8(&regs->canrier, 0);
napi_schedule(&priv->napi);
ret = IRQ_HANDLED;
} else
clear_bit(F_RX_PROGRESS, &priv->flags);
}
return ret;
}
static int mscan_do_set_mode(struct net_device *dev, enum can_mode mode)
{
struct mscan_priv *priv = netdev_priv(dev);
int ret = 0;
if (!priv->open_time)
return -EINVAL;
switch (mode) {
case CAN_MODE_SLEEP:
case CAN_MODE_STOP:
netif_stop_queue(dev);
mscan_set_mode(dev,
(mode ==
CAN_MODE_STOP) ? MSCAN_INIT_MODE :
MSCAN_SLEEP_MODE);
break;
case CAN_MODE_START:
if (priv->can.state <= CAN_STATE_BUS_OFF)
mscan_set_mode(dev, MSCAN_INIT_MODE);
ret = mscan_start(dev);
if (ret)
break;
if (netif_queue_stopped(dev))
netif_wake_queue(dev);
break;
default:
ret = -EOPNOTSUPP;
break;
}
return ret;
}
static int mscan_do_set_bittiming(struct net_device *dev)
{
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
struct can_bittiming *bt = &priv->can.bittiming;
u8 btr0, btr1;
btr0 = BTR0_SET_BRP(bt->brp) | BTR0_SET_SJW(bt->sjw);
btr1 = (BTR1_SET_TSEG1(bt->prop_seg + bt->phase_seg1) |
BTR1_SET_TSEG2(bt->phase_seg2) |
BTR1_SET_SAM(priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES));
dev_info(dev->dev.parent, "setting BTR0=0x%02x BTR1=0x%02x\n",
btr0, btr1);
out_8(&regs->canbtr0, btr0);
out_8(&regs->canbtr1, btr1);
return 0;
}
static int mscan_open(struct net_device *dev)
{
int ret;
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
/* common open */
ret = open_candev(dev);
if (ret)
return ret;
napi_enable(&priv->napi);
ret = request_irq(dev->irq, mscan_isr, 0, dev->name, dev);
if (ret < 0) {
napi_disable(&priv->napi);
printk(KERN_ERR "%s - failed to attach interrupt\n",
dev->name);
return ret;
}
priv->open_time = jiffies;
out_8(&regs->canctl1, in_8(&regs->canctl1) & ~MSCAN_LISTEN);
ret = mscan_start(dev);
if (ret)
return ret;
netif_start_queue(dev);
return 0;
}
static int mscan_close(struct net_device *dev)
{
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
netif_stop_queue(dev);
napi_disable(&priv->napi);
out_8(&regs->cantier, 0);
out_8(&regs->canrier, 0);
mscan_set_mode(dev, MSCAN_INIT_MODE);
close_candev(dev);
free_irq(dev->irq, dev);
priv->open_time = 0;
return 0;
}
static const struct net_device_ops mscan_netdev_ops = {
.ndo_open = mscan_open,
.ndo_stop = mscan_close,
.ndo_start_xmit = mscan_start_xmit,
};
int register_mscandev(struct net_device *dev, int clock_src)
{
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
u8 ctl1;
ctl1 = in_8(&regs->canctl1);
if (clock_src)
ctl1 |= MSCAN_CLKSRC;
else
ctl1 &= ~MSCAN_CLKSRC;
ctl1 |= MSCAN_CANE;
out_8(&regs->canctl1, ctl1);
udelay(100);
/* acceptance mask/acceptance code (accept everything) */
out_be16(&regs->canidar1_0, 0);
out_be16(&regs->canidar3_2, 0);
out_be16(&regs->canidar5_4, 0);
out_be16(&regs->canidar7_6, 0);
out_be16(&regs->canidmr1_0, 0xffff);
out_be16(&regs->canidmr3_2, 0xffff);
out_be16(&regs->canidmr5_4, 0xffff);
out_be16(&regs->canidmr7_6, 0xffff);
/* Two 32 bit Acceptance Filters */
out_8(&regs->canidac, MSCAN_AF_32BIT);
mscan_set_mode(dev, MSCAN_INIT_MODE);
return register_candev(dev);
}
EXPORT_SYMBOL_GPL(register_mscandev);
void unregister_mscandev(struct net_device *dev)
{
struct mscan_priv *priv = netdev_priv(dev);
struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
mscan_set_mode(dev, MSCAN_INIT_MODE);
out_8(&regs->canctl1, in_8(&regs->canctl1) & ~MSCAN_CANE);
unregister_candev(dev);
}
EXPORT_SYMBOL_GPL(unregister_mscandev);
struct net_device *alloc_mscandev(void)
{
struct net_device *dev;
struct mscan_priv *priv;
int i;
dev = alloc_candev(sizeof(struct mscan_priv), MSCAN_ECHO_SKB_MAX);
if (!dev)
return NULL;
priv = netdev_priv(dev);
dev->netdev_ops = &mscan_netdev_ops;
dev->flags |= IFF_ECHO; /* we support local echo */
netif_napi_add(dev, &priv->napi, mscan_rx_poll, 8);
priv->can.bittiming_const = &mscan_bittiming_const;
priv->can.do_set_bittiming = mscan_do_set_bittiming;
priv->can.do_set_mode = mscan_do_set_mode;
for (i = 0; i < TX_QUEUE_SIZE; i++) {
priv->tx_queue[i].id = i;
priv->tx_queue[i].mask = 1 << i;
}
return dev;
}
EXPORT_SYMBOL_GPL(alloc_mscandev);
MODULE_AUTHOR("Andrey Volkov <avolkov@varma-el.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("CAN port driver for a MSCAN based chips");
/*
* Definitions of consts/structs to drive the Freescale MSCAN.
*
* Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>,
* Varma Electronics Oy
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the version 2 of the GNU General Public License
* as published by the Free Software Foundation
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef __MSCAN_H__
#define __MSCAN_H__
#include <linux/types.h>
/* MSCAN control register 0 (CANCTL0) bits */
#define MSCAN_RXFRM 0x80
#define MSCAN_RXACT 0x40
#define MSCAN_CSWAI 0x20
#define MSCAN_SYNCH 0x10
#define MSCAN_TIME 0x08
#define MSCAN_WUPE 0x04
#define MSCAN_SLPRQ 0x02
#define MSCAN_INITRQ 0x01
/* MSCAN control register 1 (CANCTL1) bits */
#define MSCAN_CANE 0x80
#define MSCAN_CLKSRC 0x40
#define MSCAN_LOOPB 0x20
#define MSCAN_LISTEN 0x10
#define MSCAN_WUPM 0x04
#define MSCAN_SLPAK 0x02
#define MSCAN_INITAK 0x01
/* Use the MPC5200 MSCAN variant? */
#ifdef CONFIG_PPC
#define MSCAN_FOR_MPC5200
#endif
#ifdef MSCAN_FOR_MPC5200
#define MSCAN_CLKSRC_BUS 0
#define MSCAN_CLKSRC_XTAL MSCAN_CLKSRC
#else
#define MSCAN_CLKSRC_BUS MSCAN_CLKSRC
#define MSCAN_CLKSRC_XTAL 0
#endif
/* MSCAN receiver flag register (CANRFLG) bits */
#define MSCAN_WUPIF 0x80
#define MSCAN_CSCIF 0x40
#define MSCAN_RSTAT1 0x20
#define MSCAN_RSTAT0 0x10
#define MSCAN_TSTAT1 0x08
#define MSCAN_TSTAT0 0x04
#define MSCAN_OVRIF 0x02
#define MSCAN_RXF 0x01
#define MSCAN_ERR_IF (MSCAN_OVRIF | MSCAN_CSCIF)
#define MSCAN_RSTAT_MSK (MSCAN_RSTAT1 | MSCAN_RSTAT0)
#define MSCAN_TSTAT_MSK (MSCAN_TSTAT1 | MSCAN_TSTAT0)
#define MSCAN_STAT_MSK (MSCAN_RSTAT_MSK | MSCAN_TSTAT_MSK)
#define MSCAN_STATE_BUS_OFF (MSCAN_RSTAT1 | MSCAN_RSTAT0 | \
MSCAN_TSTAT1 | MSCAN_TSTAT0)
#define MSCAN_STATE_TX(canrflg) (((canrflg)&MSCAN_TSTAT_MSK)>>2)
#define MSCAN_STATE_RX(canrflg) (((canrflg)&MSCAN_RSTAT_MSK)>>4)
#define MSCAN_STATE_ACTIVE 0
#define MSCAN_STATE_WARNING 1
#define MSCAN_STATE_PASSIVE 2
#define MSCAN_STATE_BUSOFF 3
/* MSCAN receiver interrupt enable register (CANRIER) bits */
#define MSCAN_WUPIE 0x80
#define MSCAN_CSCIE 0x40
#define MSCAN_RSTATE1 0x20
#define MSCAN_RSTATE0 0x10
#define MSCAN_TSTATE1 0x08
#define MSCAN_TSTATE0 0x04
#define MSCAN_OVRIE 0x02
#define MSCAN_RXFIE 0x01
/* MSCAN transmitter flag register (CANTFLG) bits */
#define MSCAN_TXE2 0x04
#define MSCAN_TXE1 0x02
#define MSCAN_TXE0 0x01
#define MSCAN_TXE (MSCAN_TXE2 | MSCAN_TXE1 | MSCAN_TXE0)
/* MSCAN transmitter interrupt enable register (CANTIER) bits */
#define MSCAN_TXIE2 0x04
#define MSCAN_TXIE1 0x02
#define MSCAN_TXIE0 0x01
#define MSCAN_TXIE (MSCAN_TXIE2 | MSCAN_TXIE1 | MSCAN_TXIE0)
/* MSCAN transmitter message abort request (CANTARQ) bits */
#define MSCAN_ABTRQ2 0x04
#define MSCAN_ABTRQ1 0x02
#define MSCAN_ABTRQ0 0x01
/* MSCAN transmitter message abort ack (CANTAAK) bits */
#define MSCAN_ABTAK2 0x04
#define MSCAN_ABTAK1 0x02
#define MSCAN_ABTAK0 0x01
/* MSCAN transmit buffer selection (CANTBSEL) bits */
#define MSCAN_TX2 0x04
#define MSCAN_TX1 0x02
#define MSCAN_TX0 0x01
/* MSCAN ID acceptance control register (CANIDAC) bits */
#define MSCAN_IDAM1 0x20
#define MSCAN_IDAM0 0x10
#define MSCAN_IDHIT2 0x04
#define MSCAN_IDHIT1 0x02
#define MSCAN_IDHIT0 0x01
#define MSCAN_AF_32BIT 0x00
#define MSCAN_AF_16BIT MSCAN_IDAM0
#define MSCAN_AF_8BIT MSCAN_IDAM1
#define MSCAN_AF_CLOSED (MSCAN_IDAM0|MSCAN_IDAM1)
#define MSCAN_AF_MASK (~(MSCAN_IDAM0|MSCAN_IDAM1))
/* MSCAN Miscellaneous Register (CANMISC) bits */
#define MSCAN_BOHOLD 0x01
#ifdef MSCAN_FOR_MPC5200
#define _MSCAN_RESERVED_(n, num) u8 _res##n[num]
#define _MSCAN_RESERVED_DSR_SIZE 2
#else
#define _MSCAN_RESERVED_(n, num)
#define _MSCAN_RESERVED_DSR_SIZE 0
#endif
/* Structure of the hardware registers */
struct mscan_regs {
/* (see doc S12MSCANV3/D) MPC5200 MSCAN */
u8 canctl0; /* + 0x00 0x00 */
u8 canctl1; /* + 0x01 0x01 */
_MSCAN_RESERVED_(1, 2); /* + 0x02 */
u8 canbtr0; /* + 0x04 0x02 */
u8 canbtr1; /* + 0x05 0x03 */
_MSCAN_RESERVED_(2, 2); /* + 0x06 */
u8 canrflg; /* + 0x08 0x04 */
u8 canrier; /* + 0x09 0x05 */
_MSCAN_RESERVED_(3, 2); /* + 0x0a */
u8 cantflg; /* + 0x0c 0x06 */
u8 cantier; /* + 0x0d 0x07 */
_MSCAN_RESERVED_(4, 2); /* + 0x0e */
u8 cantarq; /* + 0x10 0x08 */
u8 cantaak; /* + 0x11 0x09 */
_MSCAN_RESERVED_(5, 2); /* + 0x12 */
u8 cantbsel; /* + 0x14 0x0a */
u8 canidac; /* + 0x15 0x0b */
u8 reserved; /* + 0x16 0x0c */
_MSCAN_RESERVED_(6, 5); /* + 0x17 */
#ifndef MSCAN_FOR_MPC5200
u8 canmisc; /* 0x0d */
#endif
u8 canrxerr; /* + 0x1c 0x0e */
u8 cantxerr; /* + 0x1d 0x0f */
_MSCAN_RESERVED_(7, 2); /* + 0x1e */
u16 canidar1_0; /* + 0x20 0x10 */
_MSCAN_RESERVED_(8, 2); /* + 0x22 */
u16 canidar3_2; /* + 0x24 0x12 */
_MSCAN_RESERVED_(9, 2); /* + 0x26 */
u16 canidmr1_0; /* + 0x28 0x14 */
_MSCAN_RESERVED_(10, 2); /* + 0x2a */
u16 canidmr3_2; /* + 0x2c 0x16 */
_MSCAN_RESERVED_(11, 2); /* + 0x2e */
u16 canidar5_4; /* + 0x30 0x18 */
_MSCAN_RESERVED_(12, 2); /* + 0x32 */
u16 canidar7_6; /* + 0x34 0x1a */
_MSCAN_RESERVED_(13, 2); /* + 0x36 */
u16 canidmr5_4; /* + 0x38 0x1c */
_MSCAN_RESERVED_(14, 2); /* + 0x3a */
u16 canidmr7_6; /* + 0x3c 0x1e */
_MSCAN_RESERVED_(15, 2); /* + 0x3e */
struct {
u16 idr1_0; /* + 0x40 0x20 */
_MSCAN_RESERVED_(16, 2); /* + 0x42 */
u16 idr3_2; /* + 0x44 0x22 */
_MSCAN_RESERVED_(17, 2); /* + 0x46 */
u16 dsr1_0; /* + 0x48 0x24 */
_MSCAN_RESERVED_(18, 2); /* + 0x4a */
u16 dsr3_2; /* + 0x4c 0x26 */
_MSCAN_RESERVED_(19, 2); /* + 0x4e */
u16 dsr5_4; /* + 0x50 0x28 */
_MSCAN_RESERVED_(20, 2); /* + 0x52 */
u16 dsr7_6; /* + 0x54 0x2a */
_MSCAN_RESERVED_(21, 2); /* + 0x56 */
u8 dlr; /* + 0x58 0x2c */
u8:8; /* + 0x59 0x2d */
_MSCAN_RESERVED_(22, 2); /* + 0x5a */
u16 time; /* + 0x5c 0x2e */
} rx;
_MSCAN_RESERVED_(23, 2); /* + 0x5e */
struct {
u16 idr1_0; /* + 0x60 0x30 */
_MSCAN_RESERVED_(24, 2); /* + 0x62 */
u16 idr3_2; /* + 0x64 0x32 */
_MSCAN_RESERVED_(25, 2); /* + 0x66 */
u16 dsr1_0; /* + 0x68 0x34 */
_MSCAN_RESERVED_(26, 2); /* + 0x6a */
u16 dsr3_2; /* + 0x6c 0x36 */
_MSCAN_RESERVED_(27, 2); /* + 0x6e */
u16 dsr5_4; /* + 0x70 0x38 */
_MSCAN_RESERVED_(28, 2); /* + 0x72 */
u16 dsr7_6; /* + 0x74 0x3a */
_MSCAN_RESERVED_(29, 2); /* + 0x76 */
u8 dlr; /* + 0x78 0x3c */
u8 tbpr; /* + 0x79 0x3d */
_MSCAN_RESERVED_(30, 2); /* + 0x7a */
u16 time; /* + 0x7c 0x3e */
} tx;
_MSCAN_RESERVED_(31, 2); /* + 0x7e */
} __attribute__ ((packed));
#undef _MSCAN_RESERVED_
#define MSCAN_REGION sizeof(struct mscan)
#define TX_QUEUE_SIZE 3
struct tx_queue_entry {
struct list_head list;
u8 mask;
u8 id;
};
struct mscan_priv {
struct can_priv can; /* must be the first member */
long open_time;
unsigned long flags;
void __iomem *reg_base; /* ioremap'ed address to registers */
u8 shadow_statflg;
u8 shadow_canrier;
u8 cur_pri;
u8 prev_buf_id;
u8 tx_active;
struct list_head tx_head;
struct tx_queue_entry tx_queue[TX_QUEUE_SIZE];
struct napi_struct napi;
};
struct net_device *alloc_mscandev(void);
/*
* clock_src:
* 1 = The MSCAN clock source is the onchip Bus Clock.
* 0 = The MSCAN clock source is the chip Oscillator Clock.
*/
extern int register_mscandev(struct net_device *dev, int clock_src);
extern void unregister_mscandev(struct net_device *dev);
#endif /* __MSCAN_H__ */
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