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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/pci/controller/pci-ixp4xx.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/controller/pci-ixp4xx.c')
-rw-r--r--drivers/pci/controller/pci-ixp4xx.c671
1 files changed, 671 insertions, 0 deletions
diff --git a/drivers/pci/controller/pci-ixp4xx.c b/drivers/pci/controller/pci-ixp4xx.c
new file mode 100644
index 000000000..654ac4a82
--- /dev/null
+++ b/drivers/pci/controller/pci-ixp4xx.c
@@ -0,0 +1,671 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Support for Intel IXP4xx PCI host controller
+ *
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * Based on the IXP4xx arch/arm/mach-ixp4xx/common-pci.c driver
+ * Copyright (C) 2002 Intel Corporation
+ * Copyright (C) 2003 Greg Ungerer <gerg@linux-m68k.org>
+ * Copyright (C) 2003-2004 MontaVista Software, Inc.
+ * Copyright (C) 2005 Deepak Saxena <dsaxena@plexity.net>
+ * Copyright (C) 2005 Alessandro Zummo <a.zummo@towertech.it>
+ *
+ * TODO:
+ * - Test IO-space access
+ * - DMA support
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/bits.h>
+
+/* Register offsets */
+#define IXP4XX_PCI_NP_AD 0x00
+#define IXP4XX_PCI_NP_CBE 0x04
+#define IXP4XX_PCI_NP_WDATA 0x08
+#define IXP4XX_PCI_NP_RDATA 0x0c
+#define IXP4XX_PCI_CRP_AD_CBE 0x10
+#define IXP4XX_PCI_CRP_WDATA 0x14
+#define IXP4XX_PCI_CRP_RDATA 0x18
+#define IXP4XX_PCI_CSR 0x1c
+#define IXP4XX_PCI_ISR 0x20
+#define IXP4XX_PCI_INTEN 0x24
+#define IXP4XX_PCI_DMACTRL 0x28
+#define IXP4XX_PCI_AHBMEMBASE 0x2c
+#define IXP4XX_PCI_AHBIOBASE 0x30
+#define IXP4XX_PCI_PCIMEMBASE 0x34
+#define IXP4XX_PCI_AHBDOORBELL 0x38
+#define IXP4XX_PCI_PCIDOORBELL 0x3c
+#define IXP4XX_PCI_ATPDMA0_AHBADDR 0x40
+#define IXP4XX_PCI_ATPDMA0_PCIADDR 0x44
+#define IXP4XX_PCI_ATPDMA0_LENADDR 0x48
+#define IXP4XX_PCI_ATPDMA1_AHBADDR 0x4c
+#define IXP4XX_PCI_ATPDMA1_PCIADDR 0x50
+#define IXP4XX_PCI_ATPDMA1_LENADDR 0x54
+
+/* CSR bit definitions */
+#define IXP4XX_PCI_CSR_HOST BIT(0)
+#define IXP4XX_PCI_CSR_ARBEN BIT(1)
+#define IXP4XX_PCI_CSR_ADS BIT(2)
+#define IXP4XX_PCI_CSR_PDS BIT(3)
+#define IXP4XX_PCI_CSR_ABE BIT(4)
+#define IXP4XX_PCI_CSR_DBT BIT(5)
+#define IXP4XX_PCI_CSR_ASE BIT(8)
+#define IXP4XX_PCI_CSR_IC BIT(15)
+#define IXP4XX_PCI_CSR_PRST BIT(16)
+
+/* ISR (Interrupt status) Register bit definitions */
+#define IXP4XX_PCI_ISR_PSE BIT(0)
+#define IXP4XX_PCI_ISR_PFE BIT(1)
+#define IXP4XX_PCI_ISR_PPE BIT(2)
+#define IXP4XX_PCI_ISR_AHBE BIT(3)
+#define IXP4XX_PCI_ISR_APDC BIT(4)
+#define IXP4XX_PCI_ISR_PADC BIT(5)
+#define IXP4XX_PCI_ISR_ADB BIT(6)
+#define IXP4XX_PCI_ISR_PDB BIT(7)
+
+/* INTEN (Interrupt Enable) Register bit definitions */
+#define IXP4XX_PCI_INTEN_PSE BIT(0)
+#define IXP4XX_PCI_INTEN_PFE BIT(1)
+#define IXP4XX_PCI_INTEN_PPE BIT(2)
+#define IXP4XX_PCI_INTEN_AHBE BIT(3)
+#define IXP4XX_PCI_INTEN_APDC BIT(4)
+#define IXP4XX_PCI_INTEN_PADC BIT(5)
+#define IXP4XX_PCI_INTEN_ADB BIT(6)
+#define IXP4XX_PCI_INTEN_PDB BIT(7)
+
+/* Shift value for byte enable on NP cmd/byte enable register */
+#define IXP4XX_PCI_NP_CBE_BESL 4
+
+/* PCI commands supported by NP access unit */
+#define NP_CMD_IOREAD 0x2
+#define NP_CMD_IOWRITE 0x3
+#define NP_CMD_CONFIGREAD 0xa
+#define NP_CMD_CONFIGWRITE 0xb
+#define NP_CMD_MEMREAD 0x6
+#define NP_CMD_MEMWRITE 0x7
+
+/* Constants for CRP access into local config space */
+#define CRP_AD_CBE_BESL 20
+#define CRP_AD_CBE_WRITE 0x00010000
+
+/* Special PCI configuration space registers for this controller */
+#define IXP4XX_PCI_RTOTTO 0x40
+
+struct ixp4xx_pci {
+ struct device *dev;
+ void __iomem *base;
+ bool errata_hammer;
+ bool host_mode;
+};
+
+/*
+ * The IXP4xx has a peculiar address bus that will change the
+ * byte order on SoC peripherals depending on whether the device
+ * operates in big-endian or little-endian mode. That means that
+ * readl() and writel() that always use little-endian access
+ * will not work for SoC peripherals such as the PCI controller
+ * when used in big-endian mode. The accesses to the individual
+ * PCI devices on the other hand, are always little-endian and
+ * can use readl() and writel().
+ *
+ * For local AHB bus access we need to use __raw_[readl|writel]()
+ * to make sure that we access the SoC devices in the CPU native
+ * endianness.
+ */
+static inline u32 ixp4xx_readl(struct ixp4xx_pci *p, u32 reg)
+{
+ return __raw_readl(p->base + reg);
+}
+
+static inline void ixp4xx_writel(struct ixp4xx_pci *p, u32 reg, u32 val)
+{
+ __raw_writel(val, p->base + reg);
+}
+
+static int ixp4xx_pci_check_master_abort(struct ixp4xx_pci *p)
+{
+ u32 isr = ixp4xx_readl(p, IXP4XX_PCI_ISR);
+
+ if (isr & IXP4XX_PCI_ISR_PFE) {
+ /* Make sure the master abort bit is reset */
+ ixp4xx_writel(p, IXP4XX_PCI_ISR, IXP4XX_PCI_ISR_PFE);
+ dev_dbg(p->dev, "master abort detected\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ixp4xx_pci_read_indirect(struct ixp4xx_pci *p, u32 addr, u32 cmd, u32 *data)
+{
+ ixp4xx_writel(p, IXP4XX_PCI_NP_AD, addr);
+
+ if (p->errata_hammer) {
+ int i;
+
+ /*
+ * PCI workaround - only works if NP PCI space reads have
+ * no side effects. Hammer the register and read twice 8
+ * times. last one will be good.
+ */
+ for (i = 0; i < 8; i++) {
+ ixp4xx_writel(p, IXP4XX_PCI_NP_CBE, cmd);
+ *data = ixp4xx_readl(p, IXP4XX_PCI_NP_RDATA);
+ *data = ixp4xx_readl(p, IXP4XX_PCI_NP_RDATA);
+ }
+ } else {
+ ixp4xx_writel(p, IXP4XX_PCI_NP_CBE, cmd);
+ *data = ixp4xx_readl(p, IXP4XX_PCI_NP_RDATA);
+ }
+
+ return ixp4xx_pci_check_master_abort(p);
+}
+
+static int ixp4xx_pci_write_indirect(struct ixp4xx_pci *p, u32 addr, u32 cmd, u32 data)
+{
+ ixp4xx_writel(p, IXP4XX_PCI_NP_AD, addr);
+
+ /* Set up the write */
+ ixp4xx_writel(p, IXP4XX_PCI_NP_CBE, cmd);
+
+ /* Execute the write by writing to NP_WDATA */
+ ixp4xx_writel(p, IXP4XX_PCI_NP_WDATA, data);
+
+ return ixp4xx_pci_check_master_abort(p);
+}
+
+static u32 ixp4xx_config_addr(u8 bus_num, u16 devfn, int where)
+{
+ /* Root bus is always 0 in this hardware */
+ if (bus_num == 0) {
+ /* type 0 */
+ return BIT(32-PCI_SLOT(devfn)) | ((PCI_FUNC(devfn)) << 8) |
+ (where & ~3);
+ } else {
+ /* type 1 */
+ return (bus_num << 16) | ((PCI_SLOT(devfn)) << 11) |
+ ((PCI_FUNC(devfn)) << 8) | (where & ~3) | 1;
+ }
+}
+
+/*
+ * CRP functions are "Controller Configuration Port" accesses
+ * initiated from within this driver itself to read/write PCI
+ * control information in the config space.
+ */
+static u32 ixp4xx_crp_byte_lane_enable_bits(u32 n, int size)
+{
+ if (size == 1)
+ return (0xf & ~BIT(n)) << CRP_AD_CBE_BESL;
+ if (size == 2)
+ return (0xf & ~(BIT(n) | BIT(n+1))) << CRP_AD_CBE_BESL;
+ if (size == 4)
+ return 0;
+ return 0xffffffff;
+}
+
+static int ixp4xx_crp_read_config(struct ixp4xx_pci *p, int where, int size,
+ u32 *value)
+{
+ u32 n, cmd, val;
+
+ n = where % 4;
+ cmd = where & ~3;
+
+ dev_dbg(p->dev, "%s from %d size %d cmd %08x\n",
+ __func__, where, size, cmd);
+
+ ixp4xx_writel(p, IXP4XX_PCI_CRP_AD_CBE, cmd);
+ val = ixp4xx_readl(p, IXP4XX_PCI_CRP_RDATA);
+
+ val >>= (8*n);
+ switch (size) {
+ case 1:
+ val &= U8_MAX;
+ dev_dbg(p->dev, "%s read byte %02x\n", __func__, val);
+ break;
+ case 2:
+ val &= U16_MAX;
+ dev_dbg(p->dev, "%s read word %04x\n", __func__, val);
+ break;
+ case 4:
+ val &= U32_MAX;
+ dev_dbg(p->dev, "%s read long %08x\n", __func__, val);
+ break;
+ default:
+ /* Should not happen */
+ dev_err(p->dev, "%s illegal size\n", __func__);
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ *value = val;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int ixp4xx_crp_write_config(struct ixp4xx_pci *p, int where, int size,
+ u32 value)
+{
+ u32 n, cmd, val;
+
+ n = where % 4;
+ cmd = ixp4xx_crp_byte_lane_enable_bits(n, size);
+ if (cmd == 0xffffffff)
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+ cmd |= where & ~3;
+ cmd |= CRP_AD_CBE_WRITE;
+
+ val = value << (8*n);
+
+ dev_dbg(p->dev, "%s to %d size %d cmd %08x val %08x\n",
+ __func__, where, size, cmd, val);
+
+ ixp4xx_writel(p, IXP4XX_PCI_CRP_AD_CBE, cmd);
+ ixp4xx_writel(p, IXP4XX_PCI_CRP_WDATA, val);
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+/*
+ * Then follows the functions that read and write from the common PCI
+ * configuration space.
+ */
+static u32 ixp4xx_byte_lane_enable_bits(u32 n, int size)
+{
+ if (size == 1)
+ return (0xf & ~BIT(n)) << 4;
+ if (size == 2)
+ return (0xf & ~(BIT(n) | BIT(n+1))) << 4;
+ if (size == 4)
+ return 0;
+ return 0xffffffff;
+}
+
+static int ixp4xx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *value)
+{
+ struct ixp4xx_pci *p = bus->sysdata;
+ u32 n, addr, val, cmd;
+ u8 bus_num = bus->number;
+ int ret;
+
+ *value = 0xffffffff;
+ n = where % 4;
+ cmd = ixp4xx_byte_lane_enable_bits(n, size);
+ if (cmd == 0xffffffff)
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+
+ addr = ixp4xx_config_addr(bus_num, devfn, where);
+ cmd |= NP_CMD_CONFIGREAD;
+ dev_dbg(p->dev, "read_config from %d size %d dev %d:%d:%d address: %08x cmd: %08x\n",
+ where, size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn), addr, cmd);
+
+ ret = ixp4xx_pci_read_indirect(p, addr, cmd, &val);
+ if (ret)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ val >>= (8*n);
+ switch (size) {
+ case 1:
+ val &= U8_MAX;
+ dev_dbg(p->dev, "%s read byte %02x\n", __func__, val);
+ break;
+ case 2:
+ val &= U16_MAX;
+ dev_dbg(p->dev, "%s read word %04x\n", __func__, val);
+ break;
+ case 4:
+ val &= U32_MAX;
+ dev_dbg(p->dev, "%s read long %08x\n", __func__, val);
+ break;
+ default:
+ /* Should not happen */
+ dev_err(p->dev, "%s illegal size\n", __func__);
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ *value = val;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int ixp4xx_pci_write_config(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 value)
+{
+ struct ixp4xx_pci *p = bus->sysdata;
+ u32 n, addr, val, cmd;
+ u8 bus_num = bus->number;
+ int ret;
+
+ n = where % 4;
+ cmd = ixp4xx_byte_lane_enable_bits(n, size);
+ if (cmd == 0xffffffff)
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+
+ addr = ixp4xx_config_addr(bus_num, devfn, where);
+ cmd |= NP_CMD_CONFIGWRITE;
+ val = value << (8*n);
+
+ dev_dbg(p->dev, "write_config_byte %#x to %d size %d dev %d:%d:%d addr: %08x cmd %08x\n",
+ value, where, size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn), addr, cmd);
+
+ ret = ixp4xx_pci_write_indirect(p, addr, cmd, val);
+ if (ret)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops ixp4xx_pci_ops = {
+ .read = ixp4xx_pci_read_config,
+ .write = ixp4xx_pci_write_config,
+};
+
+static u32 ixp4xx_pci_addr_to_64mconf(phys_addr_t addr)
+{
+ u8 base;
+
+ base = ((addr & 0xff000000) >> 24);
+ return (base << 24) | ((base + 1) << 16)
+ | ((base + 2) << 8) | (base + 3);
+}
+
+static int ixp4xx_pci_parse_map_ranges(struct ixp4xx_pci *p)
+{
+ struct device *dev = p->dev;
+ struct pci_host_bridge *bridge = pci_host_bridge_from_priv(p);
+ struct resource_entry *win;
+ struct resource *res;
+ phys_addr_t addr;
+
+ win = resource_list_first_type(&bridge->windows, IORESOURCE_MEM);
+ if (win) {
+ u32 pcimembase;
+
+ res = win->res;
+ addr = res->start - win->offset;
+
+ if (res->flags & IORESOURCE_PREFETCH)
+ res->name = "IXP4xx PCI PRE-MEM";
+ else
+ res->name = "IXP4xx PCI NON-PRE-MEM";
+
+ dev_dbg(dev, "%s window %pR, bus addr %pa\n",
+ res->name, res, &addr);
+ if (resource_size(res) != SZ_64M) {
+ dev_err(dev, "memory range is not 64MB\n");
+ return -EINVAL;
+ }
+
+ pcimembase = ixp4xx_pci_addr_to_64mconf(addr);
+ /* Commit configuration */
+ ixp4xx_writel(p, IXP4XX_PCI_PCIMEMBASE, pcimembase);
+ } else {
+ dev_err(dev, "no AHB memory mapping defined\n");
+ }
+
+ win = resource_list_first_type(&bridge->windows, IORESOURCE_IO);
+ if (win) {
+ res = win->res;
+
+ addr = pci_pio_to_address(res->start);
+ if (addr & 0xff) {
+ dev_err(dev, "IO mem at uneven address: %pa\n", &addr);
+ return -EINVAL;
+ }
+
+ res->name = "IXP4xx PCI IO MEM";
+ /*
+ * Setup I/O space location for PCI->AHB access, the
+ * upper 24 bits of the address goes into the lower
+ * 24 bits of this register.
+ */
+ ixp4xx_writel(p, IXP4XX_PCI_AHBIOBASE, (addr >> 8));
+ } else {
+ dev_info(dev, "no IO space AHB memory mapping defined\n");
+ }
+
+ return 0;
+}
+
+static int ixp4xx_pci_parse_map_dma_ranges(struct ixp4xx_pci *p)
+{
+ struct device *dev = p->dev;
+ struct pci_host_bridge *bridge = pci_host_bridge_from_priv(p);
+ struct resource_entry *win;
+ struct resource *res;
+ phys_addr_t addr;
+ u32 ahbmembase;
+
+ win = resource_list_first_type(&bridge->dma_ranges, IORESOURCE_MEM);
+ if (win) {
+ res = win->res;
+ addr = res->start - win->offset;
+
+ if (resource_size(res) != SZ_64M) {
+ dev_err(dev, "DMA memory range is not 64MB\n");
+ return -EINVAL;
+ }
+
+ dev_dbg(dev, "DMA MEM BASE: %pa\n", &addr);
+ /*
+ * 4 PCI-to-AHB windows of 16 MB each, write the 8 high bits
+ * into each byte of the PCI_AHBMEMBASE register.
+ */
+ ahbmembase = ixp4xx_pci_addr_to_64mconf(addr);
+ /* Commit AHB membase */
+ ixp4xx_writel(p, IXP4XX_PCI_AHBMEMBASE, ahbmembase);
+ } else {
+ dev_err(dev, "no DMA memory range defined\n");
+ }
+
+ return 0;
+}
+
+/* Only used to get context for abort handling */
+static struct ixp4xx_pci *ixp4xx_pci_abort_singleton;
+
+static int ixp4xx_pci_abort_handler(unsigned long addr, unsigned int fsr,
+ struct pt_regs *regs)
+{
+ struct ixp4xx_pci *p = ixp4xx_pci_abort_singleton;
+ u32 isr, status;
+ int ret;
+
+ isr = ixp4xx_readl(p, IXP4XX_PCI_ISR);
+ ret = ixp4xx_crp_read_config(p, PCI_STATUS, 2, &status);
+ if (ret) {
+ dev_err(p->dev, "unable to read abort status\n");
+ return -EINVAL;
+ }
+
+ dev_err(p->dev,
+ "PCI: abort_handler addr = %#lx, isr = %#x, status = %#x\n",
+ addr, isr, status);
+
+ /* Make sure the Master Abort bit is reset */
+ ixp4xx_writel(p, IXP4XX_PCI_ISR, IXP4XX_PCI_ISR_PFE);
+ status |= PCI_STATUS_REC_MASTER_ABORT;
+ ret = ixp4xx_crp_write_config(p, PCI_STATUS, 2, status);
+ if (ret)
+ dev_err(p->dev, "unable to clear abort status bit\n");
+
+ /*
+ * If it was an imprecise abort, then we need to correct the
+ * return address to be _after_ the instruction.
+ */
+ if (fsr & (1 << 10)) {
+ dev_err(p->dev, "imprecise abort\n");
+ regs->ARM_pc += 4;
+ }
+
+ return 0;
+}
+
+static int __init ixp4xx_pci_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct ixp4xx_pci *p;
+ struct pci_host_bridge *host;
+ int ret;
+ u32 val;
+ phys_addr_t addr;
+ u32 basereg[4] = {
+ PCI_BASE_ADDRESS_0,
+ PCI_BASE_ADDRESS_1,
+ PCI_BASE_ADDRESS_2,
+ PCI_BASE_ADDRESS_3,
+ };
+ int i;
+
+ host = devm_pci_alloc_host_bridge(dev, sizeof(*p));
+ if (!host)
+ return -ENOMEM;
+
+ host->ops = &ixp4xx_pci_ops;
+ p = pci_host_bridge_priv(host);
+ host->sysdata = p;
+ p->dev = dev;
+ dev_set_drvdata(dev, p);
+
+ /*
+ * Set up quirk for erratic behaviour in the 42x variant
+ * when accessing config space.
+ */
+ if (of_device_is_compatible(np, "intel,ixp42x-pci")) {
+ p->errata_hammer = true;
+ dev_info(dev, "activate hammering errata\n");
+ }
+
+ p->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(p->base))
+ return PTR_ERR(p->base);
+
+ val = ixp4xx_readl(p, IXP4XX_PCI_CSR);
+ p->host_mode = !!(val & IXP4XX_PCI_CSR_HOST);
+ dev_info(dev, "controller is in %s mode\n",
+ p->host_mode ? "host" : "option");
+
+ /* Hook in our fault handler for PCI errors */
+ ixp4xx_pci_abort_singleton = p;
+ hook_fault_code(16+6, ixp4xx_pci_abort_handler, SIGBUS, 0,
+ "imprecise external abort");
+
+ ret = ixp4xx_pci_parse_map_ranges(p);
+ if (ret)
+ return ret;
+
+ ret = ixp4xx_pci_parse_map_dma_ranges(p);
+ if (ret)
+ return ret;
+
+ /* This is only configured in host mode */
+ if (p->host_mode) {
+ addr = __pa(PAGE_OFFSET);
+ /* This is a noop (0x00) but explains what is going on */
+ addr |= PCI_BASE_ADDRESS_SPACE_MEMORY;
+
+ for (i = 0; i < 4; i++) {
+ /* Write this directly into the config space */
+ ret = ixp4xx_crp_write_config(p, basereg[i], 4, addr);
+ if (ret)
+ dev_err(dev, "failed to set up PCI_BASE_ADDRESS_%d\n", i);
+ else
+ dev_info(dev, "set PCI_BASE_ADDR_%d to %pa\n", i, &addr);
+ addr += SZ_16M;
+ }
+
+ /*
+ * Enable CSR window at 64 MiB to allow PCI masters to continue
+ * prefetching past the 64 MiB boundary, if all AHB to PCI
+ * windows are consecutive.
+ */
+ ret = ixp4xx_crp_write_config(p, PCI_BASE_ADDRESS_4, 4, addr);
+ if (ret)
+ dev_err(dev, "failed to set up PCI_BASE_ADDRESS_4\n");
+ else
+ dev_info(dev, "set PCI_BASE_ADDR_4 to %pa\n", &addr);
+
+ /*
+ * Put the IO memory window at the very end of physical memory
+ * at 0xfffffc00. This is when the system is trying to access IO
+ * memory over AHB.
+ */
+ addr = 0xfffffc00;
+ addr |= PCI_BASE_ADDRESS_SPACE_IO;
+ ret = ixp4xx_crp_write_config(p, PCI_BASE_ADDRESS_5, 4, addr);
+ if (ret)
+ dev_err(dev, "failed to set up PCI_BASE_ADDRESS_5\n");
+ else
+ dev_info(dev, "set PCI_BASE_ADDR_5 to %pa\n", &addr);
+
+ /*
+ * Retry timeout to 0x80
+ * Transfer ready timeout to 0xff
+ */
+ ret = ixp4xx_crp_write_config(p, IXP4XX_PCI_RTOTTO, 4,
+ 0x000080ff);
+ if (ret)
+ dev_err(dev, "failed to set up TRDY limit\n");
+ else
+ dev_info(dev, "set TRDY limit to 0x80ff\n");
+ }
+
+ /* Clear interrupts */
+ val = IXP4XX_PCI_ISR_PSE | IXP4XX_PCI_ISR_PFE | IXP4XX_PCI_ISR_PPE | IXP4XX_PCI_ISR_AHBE;
+ ixp4xx_writel(p, IXP4XX_PCI_ISR, val);
+
+ /*
+ * Set Initialize Complete in PCI Control Register: allow IXP4XX to
+ * generate PCI configuration cycles. Specify that the AHB bus is
+ * operating in big-endian mode. Set up byte lane swapping between
+ * little-endian PCI and the big-endian AHB bus.
+ */
+ val = IXP4XX_PCI_CSR_IC | IXP4XX_PCI_CSR_ABE;
+ if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+ val |= (IXP4XX_PCI_CSR_PDS | IXP4XX_PCI_CSR_ADS);
+ ixp4xx_writel(p, IXP4XX_PCI_CSR, val);
+
+ ret = ixp4xx_crp_write_config(p, PCI_COMMAND, 2, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
+ if (ret)
+ dev_err(dev, "unable to initialize master and command memory\n");
+ else
+ dev_info(dev, "initialized as master\n");
+
+ pci_host_probe(host);
+
+ return 0;
+}
+
+static const struct of_device_id ixp4xx_pci_of_match[] = {
+ {
+ .compatible = "intel,ixp42x-pci",
+ },
+ {
+ .compatible = "intel,ixp43x-pci",
+ },
+ {},
+};
+
+/*
+ * This driver needs to be a builtin module with suppressed bind
+ * attributes since the probe() is initializing a hard exception
+ * handler and this can only be done from __init-tagged code
+ * sections. This module cannot be removed and inserted at all.
+ */
+static struct platform_driver ixp4xx_pci_driver = {
+ .driver = {
+ .name = "ixp4xx-pci",
+ .suppress_bind_attrs = true,
+ .of_match_table = ixp4xx_pci_of_match,
+ },
+};
+builtin_platform_driver_probe(ixp4xx_pci_driver, ixp4xx_pci_probe);