PCI: v3-semi: Add V3 Semiconductor PCI host driver

This PCI host bridge from V3 Semiconductor needs no further
introduction. An ancient driver for it has been sitting in
arch/arm/mach-integrator/pci_v3.* since before v2.6.12 and the
initial migration to git.

But we need to get the drivers out of arch/arm/* and get proper handling of
the old drivers, rewrite and clean up so the PCI maintainer can control the
mass of drivers without having to run all over the kernel. We also switch
swiftly to all the new infrastructure found in the PCI hosts as of late.

Some code is preserved so I have added an extensive list of authors in the
top comment section.

This driver probes with the following result:

  OF: PCI: host bridge /pciv3@62000000 ranges:
  OF: PCI:   No bus range found for /pciv3@62000000, using [bus 00-ff]
  OF: PCI:    IO 0x60000000..0x6000ffff -> 0x00000000
  OF: PCI:   MEM 0x40000000..0x4fffffff -> 0x40000000
  OF: PCI:   MEM 0x50000000..0x5fffffff -> 0x50000000
  pci-v3-semi 62000000.pciv3: initialized PCI V3 Integrator/AP integration
  pci-v3-semi 62000000.pciv3: PCI host bridge to bus 0000:00
  pci_bus 0000:00: root bus resource [bus 00-ff]
  pci_bus 0000:00: root bus resource [io  0x0000-0xffff]
  pci_bus 0000:00: root bus resource [mem 0x40000000-0x4fffffff]
  pci_bus 0000:00: root bus resource [mem 0x50000000-0x5fffffff pref]
  pci-v3-semi 62000000.pciv3: parity error interrupt
  pci-v3-semi 62000000.pciv3: master abort error interrupt
  pci-v3-semi 62000000.pciv3: PCI target LB->PCI READ abort interrupt
  pci-v3-semi 62000000.pciv3: master abort error interrupt
  (repeats a few times)
  pci 0000:00:09.0: [1011:0024] type 01 class 0x060400
  pci-v3-semi 62000000.pciv3: master abort error interrupt
  pci-v3-semi 62000000.pciv3: PCI target LB->PCI READ abort interrupt
  pci 0000:00:0b.0: [8086:1229] type 00 class 0x020000
  pci 0000:00:0b.0: reg 0x10: [mem 0x00000000-0x00000fff pref]
  pci 0000:00:0b.0: reg 0x14: [io  0x0000-0x001f]
  pci 0000:00:0b.0: reg 0x18: [mem 0x00000000-0x000fffff]
  pci 0000:00:0b.0: reg 0x30: [mem 0x00000000-0x000fffff pref]
  pci 0000:00:0b.0: supports D1 D2
  pci 0000:00:0b.0: PME# supported from D0 D1 D2 D3hot
  pci 0000:00:0c.0: [5333:8811] type 00 class 0x030000
  pci 0000:00:0c.0: reg 0x10: [mem 0x00000000-0x03ffffff]
  pci 0000:00:0c.0: reg 0x30: [mem 0x00000000-0x0000ffff pref]
  pci 0000:00:0c.0: vgaarb: VGA device added: decodes=io+mem,owns=io,locks=none
  PCI: bus0: Fast back to back transfers disabled
  PCI: bus1: Fast back to back transfers enabled
  pci 0000:00:0c.0: BAR 0: assigned [mem 0x40000000-0x43ffffff]
  pci 0000:00:0b.0: BAR 2: assigned [mem 0x44000000-0x440fffff]
  pci 0000:00:0b.0: BAR 6: assigned [mem 0x50000000-0x500fffff pref]
  pci 0000:00:0c.0: BAR 6: assigned [mem 0x50100000-0x5010ffff pref]
  pci 0000:00:0b.0: BAR 0: assigned [mem 0x50110000-0x50110fff pref]
  pci 0000:00:0b.0: BAR 1: assigned [io  0x1000-0x101f]
  pci 0000:00:09.0: PCI bridge to [bus 01]
  pci 0000:00:0b.0: Firmware left e100 interrupts enabled; disabling
  (...)
  e100: Intel(R) PRO/100 Network Driver, 3.5.24-k2-NAPI
  e100: Copyright(c) 1999-2006 Intel Corporation
  e100 0000:00:0b.0: enabling device (0146 -> 0147)
  e100 0000:00:0b.0 eth0: addr 0x50110000, irq 31, MAC addr 00:08:c7:99:d2:57

> lspci
  00:0b.0 Class 0200: 8086:1229
  00:09.0 Class 0604: 1011:0024
  00:0c.0 Class 0300: 5333:8811

> cat /proc/iomem
  40000000-4fffffff : V3 PCI NON-PRE-MEM
    40000000-43ffffff : 0000:00:0c.0
    44000000-440fffff : 0000:00:0b.0
      44000000-440fffff : e100
  50000000-5fffffff : V3 PCI PRE-MEM
    50000000-500fffff : 0000:00:0b.0
    50100000-5010ffff : 0000:00:0c.0
    50110000-50110fff : 0000:00:0b.0
      50110000-50110fff : e100
  61000000-61ffffff : /pciv3@62000000
  62000000-6200ffff : /pciv3@62000000
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[bhelgaas: fold in %pR fixes from Arnd Bergmann <arnd@arndb.de>:
http://lkml.kernel.org/r/20171011140224.3770968-1-arnd@arndb.de]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>

MAINTAINERS

@@ -10503,6 +10503,13 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/pci/rockchip-pcie.txt
 F:	drivers/pci/host/pcie-rockchip.c
 
+PCI DRIVER FOR V3 SEMICONDUCTOR V360EPC
+M:	Linus Walleij <linus.walleij@linaro.org>
+L:	linux-pci@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/pci/v3-v360epc-pci.txt
+F:	drivers/pci/host/pci-v3-semi.c
+
 PCIE DRIVER FOR ST SPEAR13XX
 M:	Pratyush Anand <pratyush.anand@gmail.com>
 L:	linux-pci@vger.kernel.org

drivers/pci/host/Kconfig

@@ -95,6 +95,12 @@ config PCI_XGENE_MSI
 	  Say Y here if you want PCIe MSI support for the APM X-Gene v1 SoC.
 	  This MSI driver supports 5 PCIe ports on the APM X-Gene v1 SoC.
 
+config PCI_V3_SEMI
+	bool "V3 Semiconductor PCI controller"
+	depends on OF
+	depends on ARM
+	default ARCH_INTEGRATOR_AP
+
 config PCI_VERSATILE
 	bool "ARM Versatile PB PCI controller"
 	depends on ARCH_VERSATILE

drivers/pci/host/Makefile

@@ -9,6 +9,7 @@ obj-$(CONFIG_PCI_HOST_COMMON) += pci-host-common.o
 obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
 obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
 obj-$(CONFIG_PCIE_XILINX_NWL) += pcie-xilinx-nwl.o
+obj-$(CONFIG_PCI_V3_SEMI) += pci-v3-semi.o
 obj-$(CONFIG_PCI_XGENE_MSI) += pci-xgene-msi.o
 obj-$(CONFIG_PCI_VERSATILE) += pci-versatile.o
 obj-$(CONFIG_PCIE_IPROC) += pcie-iproc.o

drivers/pci/host/pci-v3-semi.c

+/*
+ * Support for V3 Semiconductor PCI Local Bus to PCI Bridge
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * Based on the code from arch/arm/mach-integrator/pci_v3.c
+ * Copyright (C) 1999 ARM Limited
+ * Copyright (C) 2000-2001 Deep Blue Solutions Ltd
+ *
+ * Contributors to the old driver include:
+ * Russell King <linux@armlinux.org.uk>
+ * David A. Rusling <david.rusling@linaro.org> (uHAL, ARM Firmware suite)
+ * Rob Herring <robh@kernel.org>
+ * Liviu Dudau <Liviu.Dudau@arm.com>
+ * Grant Likely <grant.likely@secretlab.ca>
+ * Arnd Bergmann <arnd@arndb.de>
+ * Bjorn Helgaas <bhelgaas@google.com>
+ */
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/bitops.h>
+#include <linux/irq.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/clk.h>
+
+#define V3_PCI_VENDOR			0x00000000
+#define V3_PCI_DEVICE			0x00000002
+#define V3_PCI_CMD			0x00000004
+#define V3_PCI_STAT			0x00000006
+#define V3_PCI_CC_REV			0x00000008
+#define V3_PCI_HDR_CFG			0x0000000C
+#define V3_PCI_IO_BASE			0x00000010
+#define V3_PCI_BASE0			0x00000014
+#define V3_PCI_BASE1			0x00000018
+#define V3_PCI_SUB_VENDOR		0x0000002C
+#define V3_PCI_SUB_ID			0x0000002E
+#define V3_PCI_ROM			0x00000030
+#define V3_PCI_BPARAM			0x0000003C
+#define V3_PCI_MAP0			0x00000040
+#define V3_PCI_MAP1			0x00000044
+#define V3_PCI_INT_STAT			0x00000048
+#define V3_PCI_INT_CFG			0x0000004C
+#define V3_LB_BASE0			0x00000054
+#define V3_LB_BASE1			0x00000058
+#define V3_LB_MAP0			0x0000005E
+#define V3_LB_MAP1			0x00000062
+#define V3_LB_BASE2			0x00000064
+#define V3_LB_MAP2			0x00000066
+#define V3_LB_SIZE			0x00000068
+#define V3_LB_IO_BASE			0x0000006E
+#define V3_FIFO_CFG			0x00000070
+#define V3_FIFO_PRIORITY		0x00000072
+#define V3_FIFO_STAT			0x00000074
+#define V3_LB_ISTAT			0x00000076
+#define V3_LB_IMASK			0x00000077
+#define V3_SYSTEM			0x00000078
+#define V3_LB_CFG			0x0000007A
+#define V3_PCI_CFG			0x0000007C
+#define V3_DMA_PCI_ADR0			0x00000080
+#define V3_DMA_PCI_ADR1			0x00000090
+#define V3_DMA_LOCAL_ADR0		0x00000084
+#define V3_DMA_LOCAL_ADR1		0x00000094
+#define V3_DMA_LENGTH0			0x00000088
+#define V3_DMA_LENGTH1			0x00000098
+#define V3_DMA_CSR0			0x0000008B
+#define V3_DMA_CSR1			0x0000009B
+#define V3_DMA_CTLB_ADR0		0x0000008C
+#define V3_DMA_CTLB_ADR1		0x0000009C
+#define V3_DMA_DELAY			0x000000E0
+#define V3_MAIL_DATA			0x000000C0
+#define V3_PCI_MAIL_IEWR		0x000000D0
+#define V3_PCI_MAIL_IERD		0x000000D2
+#define V3_LB_MAIL_IEWR			0x000000D4
+#define V3_LB_MAIL_IERD			0x000000D6
+#define V3_MAIL_WR_STAT			0x000000D8
+#define V3_MAIL_RD_STAT			0x000000DA
+#define V3_QBA_MAP			0x000000DC
+
+/* PCI STATUS bits */
+#define V3_PCI_STAT_PAR_ERR		BIT(15)
+#define V3_PCI_STAT_SYS_ERR		BIT(14)
+#define V3_PCI_STAT_M_ABORT_ERR		BIT(13)
+#define V3_PCI_STAT_T_ABORT_ERR		BIT(12)
+
+/* LB ISTAT bits */
+#define V3_LB_ISTAT_MAILBOX		BIT(7)
+#define V3_LB_ISTAT_PCI_RD		BIT(6)
+#define V3_LB_ISTAT_PCI_WR		BIT(5)
+#define V3_LB_ISTAT_PCI_INT		BIT(4)
+#define V3_LB_ISTAT_PCI_PERR		BIT(3)
+#define V3_LB_ISTAT_I2O_QWR		BIT(2)
+#define V3_LB_ISTAT_DMA1		BIT(1)
+#define V3_LB_ISTAT_DMA0		BIT(0)
+
+/* PCI COMMAND bits */
+#define V3_COMMAND_M_FBB_EN		BIT(9)
+#define V3_COMMAND_M_SERR_EN		BIT(8)
+#define V3_COMMAND_M_PAR_EN		BIT(6)
+#define V3_COMMAND_M_MASTER_EN		BIT(2)
+#define V3_COMMAND_M_MEM_EN		BIT(1)
+#define V3_COMMAND_M_IO_EN		BIT(0)
+
+/* SYSTEM bits */
+#define V3_SYSTEM_M_RST_OUT		BIT(15)
+#define V3_SYSTEM_M_LOCK		BIT(14)
+#define V3_SYSTEM_UNLOCK		0xa05f
+
+/* PCI CFG bits */
+#define V3_PCI_CFG_M_I2O_EN		BIT(15)
+#define V3_PCI_CFG_M_IO_REG_DIS		BIT(14)
+#define V3_PCI_CFG_M_IO_DIS		BIT(13)
+#define V3_PCI_CFG_M_EN3V		BIT(12)
+#define V3_PCI_CFG_M_RETRY_EN		BIT(10)
+#define V3_PCI_CFG_M_AD_LOW1		BIT(9)
+#define V3_PCI_CFG_M_AD_LOW0		BIT(8)
+/*
+ * This is the value applied to C/BE[3:1], with bit 0 always held 0
+ * during DMA access.
+ */
+#define V3_PCI_CFG_M_RTYPE_SHIFT	5
+#define V3_PCI_CFG_M_WTYPE_SHIFT	1
+#define V3_PCI_CFG_TYPE_DEFAULT		0x3
+
+/* PCI BASE bits (PCI -> Local Bus) */
+#define V3_PCI_BASE_M_ADR_BASE		0xFFF00000U
+#define V3_PCI_BASE_M_ADR_BASEL		0x000FFF00U
+#define V3_PCI_BASE_M_PREFETCH		BIT(3)
+#define V3_PCI_BASE_M_TYPE		(3 << 1)
+#define V3_PCI_BASE_M_IO		BIT(0)
+
+/* PCI MAP bits (PCI -> Local bus) */
+#define V3_PCI_MAP_M_MAP_ADR		0xFFF00000U
+#define V3_PCI_MAP_M_RD_POST_INH	BIT(15)
+#define V3_PCI_MAP_M_ROM_SIZE		(3 << 10)
+#define V3_PCI_MAP_M_SWAP		(3 << 8)
+#define V3_PCI_MAP_M_ADR_SIZE		0x000000F0U
+#define V3_PCI_MAP_M_REG_EN		BIT(1)
+#define V3_PCI_MAP_M_ENABLE		BIT(0)
+
+/* LB_BASE0,1 bits (Local bus -> PCI) */
+#define V3_LB_BASE_ADR_BASE		0xfff00000U
+#define V3_LB_BASE_SWAP			(3 << 8)
+#define V3_LB_BASE_ADR_SIZE		(15 << 4)
+#define V3_LB_BASE_PREFETCH		BIT(3)
+#define V3_LB_BASE_ENABLE		BIT(0)
+
+#define V3_LB_BASE_ADR_SIZE_1MB		(0 << 4)
+#define V3_LB_BASE_ADR_SIZE_2MB		(1 << 4)
+#define V3_LB_BASE_ADR_SIZE_4MB		(2 << 4)
+#define V3_LB_BASE_ADR_SIZE_8MB		(3 << 4)
+#define V3_LB_BASE_ADR_SIZE_16MB	(4 << 4)
+#define V3_LB_BASE_ADR_SIZE_32MB	(5 << 4)
+#define V3_LB_BASE_ADR_SIZE_64MB	(6 << 4)
+#define V3_LB_BASE_ADR_SIZE_128MB	(7 << 4)
+#define V3_LB_BASE_ADR_SIZE_256MB	(8 << 4)
+#define V3_LB_BASE_ADR_SIZE_512MB	(9 << 4)
+#define V3_LB_BASE_ADR_SIZE_1GB		(10 << 4)
+#define V3_LB_BASE_ADR_SIZE_2GB		(11 << 4)
+
+#define v3_addr_to_lb_base(a)	((a) & V3_LB_BASE_ADR_BASE)
+
+/* LB_MAP0,1 bits (Local bus -> PCI) */
+#define V3_LB_MAP_MAP_ADR		0xfff0U
+#define V3_LB_MAP_TYPE			(7 << 1)
+#define V3_LB_MAP_AD_LOW_EN		BIT(0)
+
+#define V3_LB_MAP_TYPE_IACK		(0 << 1)
+#define V3_LB_MAP_TYPE_IO		(1 << 1)
+#define V3_LB_MAP_TYPE_MEM		(3 << 1)
+#define V3_LB_MAP_TYPE_CONFIG		(5 << 1)
+#define V3_LB_MAP_TYPE_MEM_MULTIPLE	(6 << 1)
+
+#define v3_addr_to_lb_map(a)	(((a) >> 16) & V3_LB_MAP_MAP_ADR)
+
+/* LB_BASE2 bits (Local bus -> PCI IO) */
+#define V3_LB_BASE2_ADR_BASE		0xff00U
+#define V3_LB_BASE2_SWAP_AUTO		(3 << 6)
+#define V3_LB_BASE2_ENABLE		BIT(0)
+
+#define v3_addr_to_lb_base2(a)	(((a) >> 16) & V3_LB_BASE2_ADR_BASE)
+
+/* LB_MAP2 bits (Local bus -> PCI IO) */
+#define V3_LB_MAP2_MAP_ADR		0xff00U
+
+#define v3_addr_to_lb_map2(a)	(((a) >> 16) & V3_LB_MAP2_MAP_ADR)
+
+/* FIFO priority bits */
+#define V3_FIFO_PRIO_LOCAL		BIT(12)
+#define V3_FIFO_PRIO_LB_RD1_FLUSH_EOB	BIT(10)
+#define V3_FIFO_PRIO_LB_RD1_FLUSH_AP1	BIT(11)
+#define V3_FIFO_PRIO_LB_RD1_FLUSH_ANY	(BIT(10)|BIT(11))
+#define V3_FIFO_PRIO_LB_RD0_FLUSH_EOB	BIT(8)
+#define V3_FIFO_PRIO_LB_RD0_FLUSH_AP1	BIT(9)
+#define V3_FIFO_PRIO_LB_RD0_FLUSH_ANY	(BIT(8)|BIT(9))
+#define V3_FIFO_PRIO_PCI		BIT(4)
+#define V3_FIFO_PRIO_PCI_RD1_FLUSH_EOB	BIT(2)
+#define V3_FIFO_PRIO_PCI_RD1_FLUSH_AP1	BIT(3)
+#define V3_FIFO_PRIO_PCI_RD1_FLUSH_ANY	(BIT(2)|BIT(3))
+#define V3_FIFO_PRIO_PCI_RD0_FLUSH_EOB	BIT(0)
+#define V3_FIFO_PRIO_PCI_RD0_FLUSH_AP1	BIT(1)
+#define V3_FIFO_PRIO_PCI_RD0_FLUSH_ANY	(BIT(0)|BIT(1))
+
+/* Local bus configuration bits */
+#define V3_LB_CFG_LB_TO_64_CYCLES	0x0000
+#define V3_LB_CFG_LB_TO_256_CYCLES	BIT(13)
+#define V3_LB_CFG_LB_TO_512_CYCLES	BIT(14)
+#define V3_LB_CFG_LB_TO_1024_CYCLES	(BIT(13)|BIT(14))
+#define V3_LB_CFG_LB_RST		BIT(12)
+#define V3_LB_CFG_LB_PPC_RDY		BIT(11)
+#define V3_LB_CFG_LB_LB_INT		BIT(10)
+#define V3_LB_CFG_LB_ERR_EN		BIT(9)
+#define V3_LB_CFG_LB_RDY_EN		BIT(8)
+#define V3_LB_CFG_LB_BE_IMODE		BIT(7)
+#define V3_LB_CFG_LB_BE_OMODE		BIT(6)
+#define V3_LB_CFG_LB_ENDIAN		BIT(5)
+#define V3_LB_CFG_LB_PARK_EN		BIT(4)
+#define V3_LB_CFG_LB_FBB_DIS		BIT(2)
+
+/* ARM Integrator-specific extended control registers */
+#define INTEGRATOR_SC_PCI_OFFSET	0x18
+#define INTEGRATOR_SC_PCI_ENABLE	BIT(0)
+#define INTEGRATOR_SC_PCI_INTCLR	BIT(1)
+#define INTEGRATOR_SC_LBFADDR_OFFSET	0x20
+#define INTEGRATOR_SC_LBFCODE_OFFSET	0x24
+
+struct v3_pci {
+	struct device *dev;
+	void __iomem *base;
+	void __iomem *config_base;
+	struct pci_bus *bus;
+	u32 config_mem;
+	u32 io_mem;
+	u32 non_pre_mem;
+	u32 pre_mem;
+	phys_addr_t io_bus_addr;
+	phys_addr_t non_pre_bus_addr;
+	phys_addr_t pre_bus_addr;
+	struct regmap *map;
+};
+
+/*
+ * The V3 PCI interface chip in Integrator provides several windows from
+ * local bus memory into the PCI memory areas. Unfortunately, there
+ * are not really enough windows for our usage, therefore we reuse
+ * one of the windows for access to PCI configuration space. On the
+ * Integrator/AP, the memory map is as follows:
+ *
+ * Local Bus Memory         Usage
+ *
+ * 40000000 - 4FFFFFFF      PCI memory.  256M non-prefetchable
+ * 50000000 - 5FFFFFFF      PCI memory.  256M prefetchable
+ * 60000000 - 60FFFFFF      PCI IO.  16M
+ * 61000000 - 61FFFFFF      PCI Configuration. 16M
+ *
+ * There are three V3 windows, each described by a pair of V3 registers.
+ * These are LB_BASE0/LB_MAP0, LB_BASE1/LB_MAP1 and LB_BASE2/LB_MAP2.
+ * Base0 and Base1 can be used for any type of PCI memory access.   Base2
+ * can be used either for PCI I/O or for I20 accesses.  By default, uHAL
+ * uses this only for PCI IO space.
+ *
+ * Normally these spaces are mapped using the following base registers:
+ *
+ * Usage Local Bus Memory         Base/Map registers used
+ *
+ * Mem   40000000 - 4FFFFFFF      LB_BASE0/LB_MAP0
+ * Mem   50000000 - 5FFFFFFF      LB_BASE1/LB_MAP1
+ * IO    60000000 - 60FFFFFF      LB_BASE2/LB_MAP2
+ * Cfg   61000000 - 61FFFFFF
+ *
+ * This means that I20 and PCI configuration space accesses will fail.
+ * When PCI configuration accesses are needed (via the uHAL PCI
+ * configuration space primitives) we must remap the spaces as follows:
+ *
+ * Usage Local Bus Memory         Base/Map registers used
+ *
+ * Mem   40000000 - 4FFFFFFF      LB_BASE0/LB_MAP0
+ * Mem   50000000 - 5FFFFFFF      LB_BASE0/LB_MAP0
+ * IO    60000000 - 60FFFFFF      LB_BASE2/LB_MAP2
+ * Cfg   61000000 - 61FFFFFF      LB_BASE1/LB_MAP1
+ *
+ * To make this work, the code depends on overlapping windows working.
+ * The V3 chip translates an address by checking its range within
+ * each of the BASE/MAP pairs in turn (in ascending register number
+ * order).  It will use the first matching pair.   So, for example,
+ * if the same address is mapped by both LB_BASE0/LB_MAP0 and
+ * LB_BASE1/LB_MAP1, the V3 will use the translation from
+ * LB_BASE0/LB_MAP0.
+ *
+ * To allow PCI Configuration space access, the code enlarges the
+ * window mapped by LB_BASE0/LB_MAP0 from 256M to 512M.  This occludes
+ * the windows currently mapped by LB_BASE1/LB_MAP1 so that it can
+ * be remapped for use by configuration cycles.
+ *
+ * At the end of the PCI Configuration space accesses,
+ * LB_BASE1/LB_MAP1 is reset to map PCI Memory.  Finally the window
+ * mapped by LB_BASE0/LB_MAP0 is reduced in size from 512M to 256M to
+ * reveal the now restored LB_BASE1/LB_MAP1 window.
+ *
+ * NOTE: We do not set up I2O mapping.  I suspect that this is only
+ * for an intelligent (target) device.  Using I2O disables most of
+ * the mappings into PCI memory.
+ */
+static void __iomem *v3_map_bus(struct pci_bus *bus,
+				unsigned int devfn, int offset)
+{
+	struct v3_pci *v3 = bus->sysdata;
+	unsigned int address, mapaddress, busnr;
+
+	busnr = bus->number;
+	if (busnr == 0) {
+		int slot = PCI_SLOT(devfn);
+
+		/*
+		 * local bus segment so need a type 0 config cycle
+		 *
+		 * build the PCI configuration "address" with one-hot in
+		 * A31-A11
+		 *
+		 * mapaddress:
+		 *  3:1 = config cycle (101)
+		 *  0   = PCI A1 & A0 are 0 (0)
+		 */
+		address = PCI_FUNC(devfn) << 8;
+		mapaddress = V3_LB_MAP_TYPE_CONFIG;
+
+		if (slot > 12)
+			/*
+			 * high order bits are handled by the MAP register
+			 */
+			mapaddress |= BIT(slot - 5);
+		else
+			/*
+			 * low order bits handled directly in the address
+			 */
+			address |= BIT(slot + 11);
+	} else {
+		/*
+		 * not the local bus segment so need a type 1 config cycle
+		 *
+		 * address:
+		 *  23:16 = bus number
+		 *  15:11 = slot number (7:3 of devfn)
+		 *  10:8  = func number (2:0 of devfn)
+		 *
+		 * mapaddress:
+		 *  3:1 = config cycle (101)
+		 *  0   = PCI A1 & A0 from host bus (1)
+		 */
+		mapaddress = V3_LB_MAP_TYPE_CONFIG | V3_LB_MAP_AD_LOW_EN;
+		address = (busnr << 16) | (devfn << 8);
+	}
+
+	/*
+	 * Set up base0 to see all 512Mbytes of memory space (not
+	 * prefetchable), this frees up base1 for re-use by
+	 * configuration memory
+	 */
+	writel(v3_addr_to_lb_base(v3->non_pre_mem) |
+	       V3_LB_BASE_ADR_SIZE_512MB | V3_LB_BASE_ENABLE,
+	       v3->base + V3_LB_BASE0);
+
+	/*
+	 * Set up base1/map1 to point into configuration space.
+	 * The config mem is always 16MB.
+	 */
+	writel(v3_addr_to_lb_base(v3->config_mem) |
+	       V3_LB_BASE_ADR_SIZE_16MB | V3_LB_BASE_ENABLE,
+	       v3->base + V3_LB_BASE1);
+	writew(mapaddress, v3->base + V3_LB_MAP1);
+
+	return v3->config_base + address + offset;
+}
+
+static void v3_unmap_bus(struct v3_pci *v3)
+{
+	/*
+	 * Reassign base1 for use by prefetchable PCI memory
+	 */
+	writel(v3_addr_to_lb_base(v3->pre_mem) |
+	       V3_LB_BASE_ADR_SIZE_256MB | V3_LB_BASE_PREFETCH |
+	       V3_LB_BASE_ENABLE,
+	       v3->base + V3_LB_BASE1);
+	writew(v3_addr_to_lb_map(v3->pre_bus_addr) |
+	       V3_LB_MAP_TYPE_MEM, /* was V3_LB_MAP_TYPE_MEM_MULTIPLE */
+	       v3->base + V3_LB_MAP1);
+
+	/*
+	 * And shrink base0 back to a 256M window (NOTE: MAP0 already correct)
+	 */
+	writel(v3_addr_to_lb_base(v3->non_pre_mem) |
+	       V3_LB_BASE_ADR_SIZE_256MB | V3_LB_BASE_ENABLE,
+	       v3->base + V3_LB_BASE0);
+}
+
+static int v3_pci_read_config(struct pci_bus *bus, unsigned int fn,
+			      int config, int size, u32 *value)
+{
+	struct v3_pci *v3 = bus->sysdata;
+	int ret;
+
+	dev_dbg(&bus->dev,
+		"[read]  slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n",
+		PCI_SLOT(fn), PCI_FUNC(fn), config, size, *value);
+	ret = pci_generic_config_read(bus, fn, config, size, value);
+	v3_unmap_bus(v3);
+	return ret;
+}
+
+static int v3_pci_write_config(struct pci_bus *bus, unsigned int fn,
+				    int config, int size, u32 value)
+{
+	struct v3_pci *v3 = bus->sysdata;
+	int ret;
+
+	dev_dbg(&bus->dev,
+		"[write] slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n",
+		PCI_SLOT(fn), PCI_FUNC(fn), config, size, value);
+	ret = pci_generic_config_write(bus, fn, config, size, value);
+	v3_unmap_bus(v3);
+	return ret;
+}
+
+static struct pci_ops v3_pci_ops = {
+	.map_bus = v3_map_bus,
+	.read = v3_pci_read_config,
+	.write = v3_pci_write_config,
+};
+
+static irqreturn_t v3_irq(int irq, void *data)
+{
+	struct v3_pci *v3 = data;
+	struct device *dev = v3->dev;
+	u32 status;
+
+	status = readw(v3->base + V3_PCI_STAT);
+	if (status & V3_PCI_STAT_PAR_ERR)
+		dev_err(dev, "parity error interrupt\n");
+	if (status & V3_PCI_STAT_SYS_ERR)
+		dev_err(dev, "system error interrupt\n");
+	if (status & V3_PCI_STAT_M_ABORT_ERR)
+		dev_err(dev, "master abort error interrupt\n");
+	if (status & V3_PCI_STAT_T_ABORT_ERR)
+		dev_err(dev, "target abort error interrupt\n");
+	writew(status, v3->base + V3_PCI_STAT);
+
+	status = readb(v3->base + V3_LB_ISTAT);
+	if (status & V3_LB_ISTAT_MAILBOX)
+		dev_info(dev, "PCI mailbox interrupt\n");
+	if (status & V3_LB_ISTAT_PCI_RD)
+		dev_err(dev, "PCI target LB->PCI READ abort interrupt\n");
+	if (status & V3_LB_ISTAT_PCI_WR)
+		dev_err(dev, "PCI target LB->PCI WRITE abort interrupt\n");
+	if (status &  V3_LB_ISTAT_PCI_INT)
+		dev_info(dev, "PCI pin interrupt\n");
+	if (status & V3_LB_ISTAT_PCI_PERR)
+		dev_err(dev, "PCI parity error interrupt\n");
+	if (status & V3_LB_ISTAT_I2O_QWR)
+		dev_info(dev, "I2O inbound post queue interrupt\n");
+	if (status & V3_LB_ISTAT_DMA1)
+		dev_info(dev, "DMA channel 1 interrupt\n");
+	if (status & V3_LB_ISTAT_DMA0)
+		dev_info(dev, "DMA channel 0 interrupt\n");
+	/* Clear all possible interrupts on the local bus */
+	writeb(0, v3->base + V3_LB_ISTAT);
+	if (v3->map)
+		regmap_write(v3->map, INTEGRATOR_SC_PCI_OFFSET,
+			     INTEGRATOR_SC_PCI_ENABLE |
+			     INTEGRATOR_SC_PCI_INTCLR);
+
+	return IRQ_HANDLED;
+}
+
+static int v3_integrator_init(struct v3_pci *v3)
+{
+	unsigned int val;
+
+	v3->map =
+		syscon_regmap_lookup_by_compatible("arm,integrator-ap-syscon");
+	if (IS_ERR(v3->map)) {
+		dev_err(v3->dev, "no syscon\n");
+		return -ENODEV;
+	}
+
+	regmap_read(v3->map, INTEGRATOR_SC_PCI_OFFSET, &val);
+	/* Take the PCI bridge out of reset, clear IRQs */
+	regmap_write(v3->map, INTEGRATOR_SC_PCI_OFFSET,
+		     INTEGRATOR_SC_PCI_ENABLE |
+		     INTEGRATOR_SC_PCI_INTCLR);
+
+	if (!(val & INTEGRATOR_SC_PCI_ENABLE)) {
+		/* If we were in reset we need to sleep a bit */
+		msleep(230);
+
+		/* Set the physical base for the controller itself */
+		writel(0x6200, v3->base + V3_LB_IO_BASE);
+
+		/* Wait for the mailbox to settle after reset */
+		do {
+			writeb(0xaa, v3->base + V3_MAIL_DATA);
+			writeb(0x55, v3->base + V3_MAIL_DATA + 4);
+		} while (readb(v3->base + V3_MAIL_DATA) != 0xaa &&
+			 readb(v3->base + V3_MAIL_DATA) != 0x55);
+	}
+
+	dev_info(v3->dev, "initialized PCI V3 Integrator/AP integration\n");
+
+	return 0;
+}
+
+static int v3_pci_setup_resource(struct v3_pci *v3,
+				 resource_size_t io_base,
+				 struct pci_host_bridge *host,
+				 struct resource_entry *win)
+{
+	struct device *dev = v3->dev;
+	struct resource *mem;
+	struct resource *io;
+	int ret;
+
+	switch (resource_type(win->res)) {
+	case IORESOURCE_IO:
+		io = win->res;
+		io->name = "V3 PCI I/O";
+		v3->io_mem = io_base;
+		v3->io_bus_addr = io->start - win->offset;
+		dev_dbg(dev, "I/O window %pR, bus addr %pap\n",
+			io, &v3->io_bus_addr);
+		ret = pci_remap_iospace(io, io_base);
+		if (ret) {
+			dev_warn(dev,
+				 "error %d: failed to map resource %pR\n",
+				 ret, io);
+			return ret;
+		}
+		/* Setup window 2 - PCI I/O */
+		writel(v3_addr_to_lb_base2(v3->io_mem) |
+		       V3_LB_BASE2_ENABLE,
+		       v3->base + V3_LB_BASE2);
+		writew(v3_addr_to_lb_map2(v3->io_bus_addr),
+		       v3->base + V3_LB_MAP2);
+		break;
+	case IORESOURCE_MEM:
+		mem = win->res;
+		if (mem->flags & IORESOURCE_PREFETCH) {
+			mem->name = "V3 PCI PRE-MEM";
+			v3->pre_mem = mem->start;
+			v3->pre_bus_addr = mem->start - win->offset;
+			dev_dbg(dev, "PREFETCHABLE MEM window %pR, bus addr %pap\n",
+				mem, &v3->pre_bus_addr);
+			if (resource_size(mem) != SZ_256M) {
+				dev_err(dev, "prefetchable memory range is not 256MB\n");
+				return -EINVAL;
+			}
+			if (v3->non_pre_mem &&
+			    (mem->start != v3->non_pre_mem + SZ_256M)) {
+				dev_err(dev,
+					"prefetchable memory is not adjacent to non-prefetchable memory\n");
+				return -EINVAL;
+			}
+			/* Setup window 1 - PCI prefetchable memory */
+			writel(v3_addr_to_lb_base(v3->pre_mem) |
+			       V3_LB_BASE_ADR_SIZE_256MB |
+			       V3_LB_BASE_PREFETCH |
+			       V3_LB_BASE_ENABLE,
+			       v3->base + V3_LB_BASE1);
+			writew(v3_addr_to_lb_map(v3->pre_bus_addr) |
+			       V3_LB_MAP_TYPE_MEM, /* Was V3_LB_MAP_TYPE_MEM_MULTIPLE */
+			       v3->base + V3_LB_MAP1);
+		} else {
+			mem->name = "V3 PCI NON-PRE-MEM";
+			v3->non_pre_mem = mem->start;
+			v3->non_pre_bus_addr = mem->start - win->offset;
+			dev_dbg(dev, "NON-PREFETCHABLE MEM window %pR, bus addr %pap\n",
+				mem, &v3->non_pre_bus_addr);
+			if (resource_size(mem) != SZ_256M) {
+				dev_err(dev,
+					"non-prefetchable memory range is not 256MB\n");
+				return -EINVAL;
+			}
+			/* Setup window 0 - PCI non-prefetchable memory */
+			writel(v3_addr_to_lb_base(v3->non_pre_mem) |
+			       V3_LB_BASE_ADR_SIZE_256MB |
+			       V3_LB_BASE_ENABLE,
+			       v3->base + V3_LB_BASE0);
+			writew(v3_addr_to_lb_map(v3->non_pre_bus_addr) |
+			       V3_LB_MAP_TYPE_MEM,
+			       v3->base + V3_LB_MAP0);
+		}
+		break;
+	case IORESOURCE_BUS:
+		dev_dbg(dev, "BUS %pR\n", win->res);
+		host->busnr = win->res->start;
+		break;
+	default:
+		dev_info(dev, "Unknown resource type %lu\n",
+			 resource_type(win->res));
+		break;
+	}
+
+	return 0;
+}
+
+static int v3_get_dma_range_config(struct v3_pci *v3,
+				   struct of_pci_range *range,
+				   u32 *pci_base, u32 *pci_map)
+{
+	struct device *dev = v3->dev;
+	u64 cpu_end = range->cpu_addr + range->size - 1;
+	u64 pci_end = range->pci_addr + range->size - 1;
+	u32 val;
+
+	if (range->pci_addr & ~V3_PCI_BASE_M_ADR_BASE) {
+		dev_err(dev, "illegal range, only PCI bits 31..20 allowed\n");
+		return -EINVAL;
+	}
+	val = ((u32)range->pci_addr) & V3_PCI_BASE_M_ADR_BASE;
+	*pci_base = val;
+
+	if (range->cpu_addr & ~V3_PCI_MAP_M_MAP_ADR) {
+		dev_err(dev, "illegal range, only CPU bits 31..20 allowed\n");
+		return -EINVAL;
+	}
+	val = ((u32)range->cpu_addr) & V3_PCI_MAP_M_MAP_ADR;
+
+	switch (range->size) {
+	case SZ_1M:
+		val |= V3_LB_BASE_ADR_SIZE_1MB;
+		break;
+	case SZ_2M:
+		val |= V3_LB_BASE_ADR_SIZE_2MB;
+		break;
+	case SZ_4M:
+		val |= V3_LB_BASE_ADR_SIZE_4MB;
+		break;
+	case SZ_8M:
+		val |= V3_LB_BASE_ADR_SIZE_8MB;
+		break;
+	case SZ_16M:
+		val |= V3_LB_BASE_ADR_SIZE_16MB;
+		break;
+	case SZ_32M:
+		val |= V3_LB_BASE_ADR_SIZE_32MB;
+		break;
+	case SZ_64M:
+		val |= V3_LB_BASE_ADR_SIZE_64MB;
+		break;
+	case SZ_128M:
+		val |= V3_LB_BASE_ADR_SIZE_128MB;
+		break;
+	case SZ_256M:
+		val |= V3_LB_BASE_ADR_SIZE_256MB;
+		break;
+	case SZ_512M:
+		val |= V3_LB_BASE_ADR_SIZE_512MB;
+		break;
+	case SZ_1G:
+		val |= V3_LB_BASE_ADR_SIZE_1GB;
+		break;
+	case SZ_2G:
+		val |= V3_LB_BASE_ADR_SIZE_2GB;
+		break;
+	default:
+		dev_err(v3->dev, "illegal dma memory chunk size\n");
+		return -EINVAL;
+		break;
+	};
+	val |= V3_PCI_MAP_M_REG_EN | V3_PCI_MAP_M_ENABLE;
+	*pci_map = val;
+
+	dev_dbg(dev,
+		"DMA MEM CPU: 0x%016llx -> 0x%016llx => "
+		"PCI: 0x%016llx -> 0x%016llx base %08x map %08x\n",
+		range->cpu_addr, cpu_end,
+		range->pci_addr, pci_end,
+		*pci_base, *pci_map);
+
+	return 0;
+}
+
+static int v3_pci_parse_map_dma_ranges(struct v3_pci *v3,
+				       struct device_node *np)
+{
+	struct of_pci_range range;
+	struct of_pci_range_parser parser;
+	struct device *dev = v3->dev;
+	int i = 0;
+
+	if (of_pci_dma_range_parser_init(&parser, np)) {
+		dev_err(dev, "missing dma-ranges property\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Get the dma-ranges from the device tree
+	 */
+	for_each_of_pci_range(&parser, &range) {
+		int ret;
+		u32 pci_base, pci_map;
+
+		ret = v3_get_dma_range_config(v3, &range, &pci_base, &pci_map);
+		if (ret)
+			return ret;
+
+		if (i == 0) {
+			writel(pci_base, v3->base + V3_PCI_BASE0);
+			writel(pci_map, v3->base + V3_PCI_MAP0);
+		} else if (i == 1) {
+			writel(pci_base, v3->base + V3_PCI_BASE1);
+			writel(pci_map, v3->base + V3_PCI_MAP1);
+		} else {
+			dev_err(dev, "too many ranges, only two supported\n");
+			dev_err(dev, "range %d ignored\n", i);
+		}
+		i++;
+	}
+	return 0;
+}
+
+static int v3_pci_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	resource_size_t io_base;
+	struct resource *regs;
+	struct resource_entry *win;
+	struct v3_pci *v3;
+	struct pci_host_bridge *host;
+	struct clk *clk;
+	u16 val;
+	int irq;
+	int ret;
+	LIST_HEAD(res);
+
+	host = pci_alloc_host_bridge(sizeof(*v3));
+	if (!host)
+		return -ENOMEM;
+
+	host->dev.parent = dev;
+	host->ops = &v3_pci_ops;
+	host->busnr = 0;
+	host->msi = NULL;
+	host->map_irq = of_irq_parse_and_map_pci;
+	host->swizzle_irq = pci_common_swizzle;
+	v3 = pci_host_bridge_priv(host);
+	host->sysdata = v3;
+	v3->dev = dev;
+
+	/* Get and enable host clock */
+	clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(clk)) {
+		dev_err(dev, "clock not found\n");
+		return PTR_ERR(clk);
+	}
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		dev_err(dev, "unable to enable clock\n");
+		return ret;
+	}
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	v3->base = devm_ioremap_resource(dev, regs);
+	if (IS_ERR(v3->base))
+		return PTR_ERR(v3->base);
+	/*
+	 * The hardware has a register with the physical base address
+	 * of the V3 controller itself, verify that this is the same
+	 * as the physical memory we've remapped it from.
+	 */
+	if (readl(v3->base + V3_LB_IO_BASE) != (regs->start >> 16))
+		dev_err(dev, "V3_LB_IO_BASE = %08x but device is @%pR\n",
+			readl(v3->base + V3_LB_IO_BASE), regs);
+
+	/* Configuration space is 16MB directly mapped */
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (resource_size(regs) != SZ_16M) {
+		dev_err(dev, "config mem is not 16MB!\n");
+		return -EINVAL;
+	}
+	v3->config_mem = regs->start;
+	v3->config_base = devm_ioremap_resource(dev, regs);
+	if (IS_ERR(v3->config_base))
+		return PTR_ERR(v3->config_base);
+
+	ret = of_pci_get_host_bridge_resources(np, 0, 0xff, &res, &io_base);
+	if (ret)
+		return ret;
+
+	ret = devm_request_pci_bus_resources(dev, &res);
+	if (ret)
+		return ret;
+
+	/* Get and request error IRQ resource */
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0) {
+		dev_err(dev, "unable to obtain PCIv3 error IRQ\n");
+		return -ENODEV;
+	}
+	ret = devm_request_irq(dev, irq, v3_irq, 0,
+			"PCIv3 error", v3);
+	if (ret < 0) {
+		dev_err(dev,
+			"unable to request PCIv3 error IRQ %d (%d)\n",
+			irq, ret);
+		return ret;
+	}
+
+	/*
+	 * Unlock V3 registers, but only if they were previously locked.
+	 */
+	if (readw(v3->base + V3_SYSTEM) & V3_SYSTEM_M_LOCK)
+		writew(V3_SYSTEM_UNLOCK, v3->base + V3_SYSTEM);
+
+	/* Disable all slave access while we set up the windows */
+	val = readw(v3->base + V3_PCI_CMD);
+	val &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
+	writew(val, v3->base + V3_PCI_CMD);
+
+	/* Put the PCI bus into reset */
+	val = readw(v3->base + V3_SYSTEM);
+	val &= ~V3_SYSTEM_M_RST_OUT;
+	writew(val, v3->base + V3_SYSTEM);
+
+	/* Retry until we're ready */
+	val = readw(v3->base + V3_PCI_CFG);
+	val |= V3_PCI_CFG_M_RETRY_EN;
+	writew(val, v3->base + V3_PCI_CFG);
+
+	/* Set up the local bus protocol */
+	val = readw(v3->base + V3_LB_CFG);
+	val |= V3_LB_CFG_LB_BE_IMODE; /* Byte enable input */
+	val |= V3_LB_CFG_LB_BE_OMODE; /* Byte enable output */
+	val &= ~V3_LB_CFG_LB_ENDIAN; /* Little endian */
+	val &= ~V3_LB_CFG_LB_PPC_RDY; /* TODO: when using on PPC403Gx, set to 1 */
+	writew(val, v3->base + V3_LB_CFG);
+
+	/* Enable the PCI bus master */
+	val = readw(v3->base + V3_PCI_CMD);
+	val |= PCI_COMMAND_MASTER;
+	writew(val, v3->base + V3_PCI_CMD);
+
+	/* Get the I/O and memory ranges from DT */
+	resource_list_for_each_entry(win, &res) {
+		ret = v3_pci_setup_resource(v3, io_base, host, win);
+		if (ret) {
+			dev_err(dev, "error setting up resources\n");
+			return ret;
+		}
+	}
+	ret = v3_pci_parse_map_dma_ranges(v3, np);
+	if (ret)
+		return ret;
+
+	/*
+	 * Disable PCI to host IO cycles, enable I/O buffers @3.3V,
+	 * set AD_LOW0 to 1 if one of the LB_MAP registers choose
+	 * to use this (should be unused).
+	 */
+	writel(0x00000000, v3->base + V3_PCI_IO_BASE);
+	val = V3_PCI_CFG_M_IO_REG_DIS | V3_PCI_CFG_M_IO_DIS |
+		V3_PCI_CFG_M_EN3V | V3_PCI_CFG_M_AD_LOW0;
+	/*
+	 * DMA read and write from PCI bus commands types
+	 */
+	val |=  V3_PCI_CFG_TYPE_DEFAULT << V3_PCI_CFG_M_RTYPE_SHIFT;
+	val |=  V3_PCI_CFG_TYPE_DEFAULT << V3_PCI_CFG_M_WTYPE_SHIFT;
+	writew(val, v3->base + V3_PCI_CFG);
+
+	/*
+	 * Set the V3 FIFO such that writes have higher priority than
+	 * reads, and local bus write causes local bus read fifo flush
+	 * on aperture 1. Same for PCI.
+	 */
+	writew(V3_FIFO_PRIO_LB_RD1_FLUSH_AP1 |
+	       V3_FIFO_PRIO_LB_RD0_FLUSH_AP1 |
+	       V3_FIFO_PRIO_PCI_RD1_FLUSH_AP1 |
+	       V3_FIFO_PRIO_PCI_RD0_FLUSH_AP1,
+	       v3->base + V3_FIFO_PRIORITY);
+
+
+	/*
+	 * Clear any error interrupts, and enable parity and write error
+	 * interrupts
+	 */
+	writeb(0, v3->base + V3_LB_ISTAT);
+	val = readw(v3->base + V3_LB_CFG);
+	val |= V3_LB_CFG_LB_LB_INT;
+	writew(val, v3->base + V3_LB_CFG);
+	writeb(V3_LB_ISTAT_PCI_WR | V3_LB_ISTAT_PCI_PERR,
+	       v3->base + V3_LB_IMASK);
+
+	/* Special Integrator initialization */
+	if (of_device_is_compatible(np, "arm,integrator-ap-pci")) {
+		ret = v3_integrator_init(v3);
+		if (ret)
+			return ret;
+	}
+
+	/* Post-init: enable PCI memory and invalidate (master already on) */
+	val = readw(v3->base + V3_PCI_CMD);
+	val |= PCI_COMMAND_MEMORY | PCI_COMMAND_INVALIDATE;
+	writew(val, v3->base + V3_PCI_CMD);
+
+	/* Clear pending interrupts */
+	writeb(0, v3->base + V3_LB_ISTAT);
+	/* Read or write errors and parity errors cause interrupts */
+	writeb(V3_LB_ISTAT_PCI_RD | V3_LB_ISTAT_PCI_WR | V3_LB_ISTAT_PCI_PERR,
+	       v3->base + V3_LB_IMASK);
+
+	/* Take the PCI bus out of reset so devices can initialize */
+	val = readw(v3->base + V3_SYSTEM);
+	val |= V3_SYSTEM_M_RST_OUT;
+	writew(val, v3->base + V3_SYSTEM);
+
+	/*
+	 * Re-lock the system register.
+	 */
+	val = readw(v3->base + V3_SYSTEM);
+	val |= V3_SYSTEM_M_LOCK;
+	writew(val, v3->base + V3_SYSTEM);
+
+	list_splice_init(&res, &host->windows);
+	ret = pci_scan_root_bus_bridge(host);
+	if (ret) {
+		dev_err(dev, "failed to register host: %d\n", ret);
+		return ret;
+	}
+	v3->bus = host->bus;
+
+	pci_bus_assign_resources(v3->bus);
+	pci_bus_add_devices(v3->bus);
+
+	return 0;
+}
+
+static const struct of_device_id v3_pci_of_match[] = {
+	{
+		.compatible = "v3,v360epc-pci",
+	},
+	{},
+};
+
+static struct platform_driver v3_pci_driver = {
+	.driver = {
+		.name = "pci-v3-semi",
+		.of_match_table = of_match_ptr(v3_pci_of_match),
+		.suppress_bind_attrs = true,
+	},
+	.probe  = v3_pci_probe,
+};
+builtin_platform_driver(v3_pci_driver);