1 files changed, 672 insertions, 0 deletions

diff --git a/drivers/pci/controller/pci-ixp4xx.c b/drivers/pci/controller/pci-ixp4xx.c
new file mode 100644
index 0000000000..acb85e0d56
--- /dev/null
+++ b/drivers/pci/controller/pci-ixp4xx.c
@@ -0,0 +1,672 @@
+// 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.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/bits.h>
+#include "../pci.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 (PCI_CONF1_ADDRESS(0, 0, PCI_FUNC(devfn), where) &
+			~PCI_CONF1_ENABLE) | BIT(32-PCI_SLOT(devfn));
+	} else {
+		/* type 1 */
+		return (PCI_CONF1_ADDRESS(bus_num, PCI_SLOT(devfn),
+					  PCI_FUNC(devfn), where) &
+			~PCI_CONF1_ENABLE) | 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);