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1// SPDX-License-Identifier: GPL-2.02/*3 * Support for Intel IXP4xx PCI host controller4 *5 * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>6 *7 * Based on the IXP4xx arch/arm/mach-ixp4xx/common-pci.c driver8 * Copyright (C) 2002 Intel Corporation9 * Copyright (C) 2003 Greg Ungerer <gerg@linux-m68k.org>10 * Copyright (C) 2003-2004 MontaVista Software, Inc.11 * Copyright (C) 2005 Deepak Saxena <dsaxena@plexity.net>12 * Copyright (C) 2005 Alessandro Zummo <a.zummo@towertech.it>13 *14 * TODO:15 * - Test IO-space access16 * - DMA support17 */18 19#include <linux/init.h>20#include <linux/io.h>21#include <linux/kernel.h>22#include <linux/of.h>23#include <linux/of_pci.h>24#include <linux/pci.h>25#include <linux/platform_device.h>26#include <linux/slab.h>27#include <linux/bits.h>28#include "../pci.h"29 30/* Register offsets */31#define IXP4XX_PCI_NP_AD		0x0032#define IXP4XX_PCI_NP_CBE		0x0433#define IXP4XX_PCI_NP_WDATA		0x0834#define IXP4XX_PCI_NP_RDATA		0x0c35#define IXP4XX_PCI_CRP_AD_CBE		0x1036#define IXP4XX_PCI_CRP_WDATA		0x1437#define IXP4XX_PCI_CRP_RDATA		0x1838#define IXP4XX_PCI_CSR			0x1c39#define IXP4XX_PCI_ISR			0x2040#define IXP4XX_PCI_INTEN		0x2441#define IXP4XX_PCI_DMACTRL		0x2842#define IXP4XX_PCI_AHBMEMBASE		0x2c43#define IXP4XX_PCI_AHBIOBASE		0x3044#define IXP4XX_PCI_PCIMEMBASE		0x3445#define IXP4XX_PCI_AHBDOORBELL		0x3846#define IXP4XX_PCI_PCIDOORBELL		0x3c47#define IXP4XX_PCI_ATPDMA0_AHBADDR	0x4048#define IXP4XX_PCI_ATPDMA0_PCIADDR	0x4449#define IXP4XX_PCI_ATPDMA0_LENADDR	0x4850#define IXP4XX_PCI_ATPDMA1_AHBADDR	0x4c51#define IXP4XX_PCI_ATPDMA1_PCIADDR	0x5052#define IXP4XX_PCI_ATPDMA1_LENADDR	0x5453 54/* CSR bit definitions */55#define IXP4XX_PCI_CSR_HOST		BIT(0)56#define IXP4XX_PCI_CSR_ARBEN		BIT(1)57#define IXP4XX_PCI_CSR_ADS		BIT(2)58#define IXP4XX_PCI_CSR_PDS		BIT(3)59#define IXP4XX_PCI_CSR_ABE		BIT(4)60#define IXP4XX_PCI_CSR_DBT		BIT(5)61#define IXP4XX_PCI_CSR_ASE		BIT(8)62#define IXP4XX_PCI_CSR_IC		BIT(15)63#define IXP4XX_PCI_CSR_PRST		BIT(16)64 65/* ISR (Interrupt status) Register bit definitions */66#define IXP4XX_PCI_ISR_PSE		BIT(0)67#define IXP4XX_PCI_ISR_PFE		BIT(1)68#define IXP4XX_PCI_ISR_PPE		BIT(2)69#define IXP4XX_PCI_ISR_AHBE		BIT(3)70#define IXP4XX_PCI_ISR_APDC		BIT(4)71#define IXP4XX_PCI_ISR_PADC		BIT(5)72#define IXP4XX_PCI_ISR_ADB		BIT(6)73#define IXP4XX_PCI_ISR_PDB		BIT(7)74 75/* INTEN (Interrupt Enable) Register bit definitions */76#define IXP4XX_PCI_INTEN_PSE		BIT(0)77#define IXP4XX_PCI_INTEN_PFE		BIT(1)78#define IXP4XX_PCI_INTEN_PPE		BIT(2)79#define IXP4XX_PCI_INTEN_AHBE		BIT(3)80#define IXP4XX_PCI_INTEN_APDC		BIT(4)81#define IXP4XX_PCI_INTEN_PADC		BIT(5)82#define IXP4XX_PCI_INTEN_ADB		BIT(6)83#define IXP4XX_PCI_INTEN_PDB		BIT(7)84 85/* Shift value for byte enable on NP cmd/byte enable register */86#define IXP4XX_PCI_NP_CBE_BESL		487 88/* PCI commands supported by NP access unit */89#define NP_CMD_IOREAD			0x290#define NP_CMD_IOWRITE			0x391#define NP_CMD_CONFIGREAD		0xa92#define NP_CMD_CONFIGWRITE		0xb93#define NP_CMD_MEMREAD			0x694#define	NP_CMD_MEMWRITE			0x795 96/* Constants for CRP access into local config space */97#define CRP_AD_CBE_BESL         2098#define CRP_AD_CBE_WRITE	0x0001000099 100/* Special PCI configuration space registers for this controller */101#define IXP4XX_PCI_RTOTTO		0x40102 103struct ixp4xx_pci {104	struct device *dev;105	void __iomem *base;106	bool errata_hammer;107	bool host_mode;108};109 110/*111 * The IXP4xx has a peculiar address bus that will change the112 * byte order on SoC peripherals depending on whether the device113 * operates in big-endian or little-endian mode. That means that114 * readl() and writel() that always use little-endian access115 * will not work for SoC peripherals such as the PCI controller116 * when used in big-endian mode. The accesses to the individual117 * PCI devices on the other hand, are always little-endian and118 * can use readl() and writel().119 *120 * For local AHB bus access we need to use __raw_[readl|writel]()121 * to make sure that we access the SoC devices in the CPU native122 * endianness.123 */124static inline u32 ixp4xx_readl(struct ixp4xx_pci *p, u32 reg)125{126	return __raw_readl(p->base + reg);127}128 129static inline void ixp4xx_writel(struct ixp4xx_pci *p, u32 reg, u32 val)130{131	__raw_writel(val, p->base + reg);132}133 134static int ixp4xx_pci_check_master_abort(struct ixp4xx_pci *p)135{136	u32 isr = ixp4xx_readl(p, IXP4XX_PCI_ISR);137 138	if (isr & IXP4XX_PCI_ISR_PFE) {139		/* Make sure the master abort bit is reset */140		ixp4xx_writel(p, IXP4XX_PCI_ISR, IXP4XX_PCI_ISR_PFE);141		dev_dbg(p->dev, "master abort detected\n");142		return -EINVAL;143	}144 145	return 0;146}147 148static int ixp4xx_pci_read_indirect(struct ixp4xx_pci *p, u32 addr, u32 cmd, u32 *data)149{150	ixp4xx_writel(p, IXP4XX_PCI_NP_AD, addr);151 152	if (p->errata_hammer) {153		int i;154 155		/*156		 * PCI workaround - only works if NP PCI space reads have157		 * no side effects. Hammer the register and read twice 8158		 * times. last one will be good.159		 */160		for (i = 0; i < 8; i++) {161			ixp4xx_writel(p, IXP4XX_PCI_NP_CBE, cmd);162			*data = ixp4xx_readl(p, IXP4XX_PCI_NP_RDATA);163			*data = ixp4xx_readl(p, IXP4XX_PCI_NP_RDATA);164		}165	} else {166		ixp4xx_writel(p, IXP4XX_PCI_NP_CBE, cmd);167		*data = ixp4xx_readl(p, IXP4XX_PCI_NP_RDATA);168	}169 170	return ixp4xx_pci_check_master_abort(p);171}172 173static int ixp4xx_pci_write_indirect(struct ixp4xx_pci *p, u32 addr, u32 cmd, u32 data)174{175	ixp4xx_writel(p, IXP4XX_PCI_NP_AD, addr);176 177	/* Set up the write */178	ixp4xx_writel(p, IXP4XX_PCI_NP_CBE, cmd);179 180	/* Execute the write by writing to NP_WDATA */181	ixp4xx_writel(p, IXP4XX_PCI_NP_WDATA, data);182 183	return ixp4xx_pci_check_master_abort(p);184}185 186static u32 ixp4xx_config_addr(u8 bus_num, u16 devfn, int where)187{188	/* Root bus is always 0 in this hardware */189	if (bus_num == 0) {190		/* type 0 */191		return (PCI_CONF1_ADDRESS(0, 0, PCI_FUNC(devfn), where) &192			~PCI_CONF1_ENABLE) | BIT(32-PCI_SLOT(devfn));193	} else {194		/* type 1 */195		return (PCI_CONF1_ADDRESS(bus_num, PCI_SLOT(devfn),196					  PCI_FUNC(devfn), where) &197			~PCI_CONF1_ENABLE) | 1;198	}199}200 201/*202 * CRP functions are "Controller Configuration Port" accesses203 * initiated from within this driver itself to read/write PCI204 * control information in the config space.205 */206static u32 ixp4xx_crp_byte_lane_enable_bits(u32 n, int size)207{208	if (size == 1)209		return (0xf & ~BIT(n)) << CRP_AD_CBE_BESL;210	if (size == 2)211		return (0xf & ~(BIT(n) | BIT(n+1))) << CRP_AD_CBE_BESL;212	if (size == 4)213		return 0;214	return 0xffffffff;215}216 217static int ixp4xx_crp_read_config(struct ixp4xx_pci *p, int where, int size,218				  u32 *value)219{220	u32 n, cmd, val;221 222	n = where % 4;223	cmd = where & ~3;224 225	dev_dbg(p->dev, "%s from %d size %d cmd %08x\n",226		__func__, where, size, cmd);227 228	ixp4xx_writel(p, IXP4XX_PCI_CRP_AD_CBE, cmd);229	val = ixp4xx_readl(p, IXP4XX_PCI_CRP_RDATA);230 231	val >>= (8*n);232	switch (size) {233	case 1:234		val &= U8_MAX;235		dev_dbg(p->dev, "%s read byte %02x\n", __func__, val);236		break;237	case 2:238		val &= U16_MAX;239		dev_dbg(p->dev, "%s read word %04x\n", __func__, val);240		break;241	case 4:242		val &= U32_MAX;243		dev_dbg(p->dev, "%s read long %08x\n", __func__, val);244		break;245	default:246		/* Should not happen */247		dev_err(p->dev, "%s illegal size\n", __func__);248		return PCIBIOS_DEVICE_NOT_FOUND;249	}250	*value = val;251 252	return PCIBIOS_SUCCESSFUL;253}254 255static int ixp4xx_crp_write_config(struct ixp4xx_pci *p, int where, int size,256				   u32 value)257{258	u32 n, cmd, val;259 260	n = where % 4;261	cmd = ixp4xx_crp_byte_lane_enable_bits(n, size);262	if (cmd == 0xffffffff)263		return PCIBIOS_BAD_REGISTER_NUMBER;264	cmd |= where & ~3;265	cmd |= CRP_AD_CBE_WRITE;266 267	val = value << (8*n);268 269	dev_dbg(p->dev, "%s to %d size %d cmd %08x val %08x\n",270		__func__, where, size, cmd, val);271 272	ixp4xx_writel(p, IXP4XX_PCI_CRP_AD_CBE, cmd);273	ixp4xx_writel(p, IXP4XX_PCI_CRP_WDATA, val);274 275	return PCIBIOS_SUCCESSFUL;276}277 278/*279 * Then follows the functions that read and write from the common PCI280 * configuration space.281 */282static u32 ixp4xx_byte_lane_enable_bits(u32 n, int size)283{284	if (size == 1)285		return (0xf & ~BIT(n)) << 4;286	if (size == 2)287		return (0xf & ~(BIT(n) | BIT(n+1))) << 4;288	if (size == 4)289		return 0;290	return 0xffffffff;291}292 293static int ixp4xx_pci_read_config(struct pci_bus *bus, unsigned int devfn,294				  int where, int size, u32 *value)295{296	struct ixp4xx_pci *p = bus->sysdata;297	u32 n, addr, val, cmd;298	u8 bus_num = bus->number;299	int ret;300 301	*value = 0xffffffff;302	n = where % 4;303	cmd = ixp4xx_byte_lane_enable_bits(n, size);304	if (cmd == 0xffffffff)305		return PCIBIOS_BAD_REGISTER_NUMBER;306 307	addr = ixp4xx_config_addr(bus_num, devfn, where);308	cmd |= NP_CMD_CONFIGREAD;309	dev_dbg(p->dev, "read_config from %d size %d dev %d:%d:%d address: %08x cmd: %08x\n",310		where, size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn), addr, cmd);311 312	ret = ixp4xx_pci_read_indirect(p, addr, cmd, &val);313	if (ret)314		return PCIBIOS_DEVICE_NOT_FOUND;315 316	val >>= (8*n);317	switch (size) {318	case 1:319		val &= U8_MAX;320		dev_dbg(p->dev, "%s read byte %02x\n", __func__, val);321		break;322	case 2:323		val &= U16_MAX;324		dev_dbg(p->dev, "%s read word %04x\n", __func__, val);325		break;326	case 4:327		val &= U32_MAX;328		dev_dbg(p->dev, "%s read long %08x\n", __func__, val);329		break;330	default:331		/* Should not happen */332		dev_err(p->dev, "%s illegal size\n", __func__);333		return PCIBIOS_DEVICE_NOT_FOUND;334	}335	*value = val;336 337	return PCIBIOS_SUCCESSFUL;338}339 340static int ixp4xx_pci_write_config(struct pci_bus *bus,  unsigned int devfn,341				   int where, int size, u32 value)342{343	struct ixp4xx_pci *p = bus->sysdata;344	u32 n, addr, val, cmd;345	u8 bus_num = bus->number;346	int ret;347 348	n = where % 4;349	cmd = ixp4xx_byte_lane_enable_bits(n, size);350	if (cmd == 0xffffffff)351		return PCIBIOS_BAD_REGISTER_NUMBER;352 353	addr = ixp4xx_config_addr(bus_num, devfn, where);354	cmd |= NP_CMD_CONFIGWRITE;355	val = value << (8*n);356 357	dev_dbg(p->dev, "write_config_byte %#x to %d size %d dev %d:%d:%d addr: %08x cmd %08x\n",358		value, where, size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn), addr, cmd);359 360	ret = ixp4xx_pci_write_indirect(p, addr, cmd, val);361	if (ret)362		return PCIBIOS_DEVICE_NOT_FOUND;363 364	return PCIBIOS_SUCCESSFUL;365}366 367static struct pci_ops ixp4xx_pci_ops = {368	.read = ixp4xx_pci_read_config,369	.write = ixp4xx_pci_write_config,370};371 372static u32 ixp4xx_pci_addr_to_64mconf(phys_addr_t addr)373{374	u8 base;375 376	base = ((addr & 0xff000000) >> 24);377	return (base << 24) | ((base + 1) << 16)378		| ((base + 2) << 8) | (base + 3);379}380 381static int ixp4xx_pci_parse_map_ranges(struct ixp4xx_pci *p)382{383	struct device *dev = p->dev;384	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(p);385	struct resource_entry *win;386	struct resource *res;387	phys_addr_t addr;388 389	win = resource_list_first_type(&bridge->windows, IORESOURCE_MEM);390	if (win) {391		u32 pcimembase;392 393		res = win->res;394		addr = res->start - win->offset;395 396		if (res->flags & IORESOURCE_PREFETCH)397			res->name = "IXP4xx PCI PRE-MEM";398		else399			res->name = "IXP4xx PCI NON-PRE-MEM";400 401		dev_dbg(dev, "%s window %pR, bus addr %pa\n",402			res->name, res, &addr);403		if (resource_size(res) != SZ_64M) {404			dev_err(dev, "memory range is not 64MB\n");405			return -EINVAL;406		}407 408		pcimembase = ixp4xx_pci_addr_to_64mconf(addr);409		/* Commit configuration */410		ixp4xx_writel(p, IXP4XX_PCI_PCIMEMBASE, pcimembase);411	} else {412		dev_err(dev, "no AHB memory mapping defined\n");413	}414 415	win = resource_list_first_type(&bridge->windows, IORESOURCE_IO);416	if (win) {417		res = win->res;418 419		addr = pci_pio_to_address(res->start);420		if (addr & 0xff) {421			dev_err(dev, "IO mem at uneven address: %pa\n", &addr);422			return -EINVAL;423		}424 425		res->name = "IXP4xx PCI IO MEM";426		/*427		 * Setup I/O space location for PCI->AHB access, the428		 * upper 24 bits of the address goes into the lower429		 * 24 bits of this register.430		 */431		ixp4xx_writel(p, IXP4XX_PCI_AHBIOBASE, (addr >> 8));432	} else {433		dev_info(dev, "no IO space AHB memory mapping defined\n");434	}435 436	return 0;437}438 439static int ixp4xx_pci_parse_map_dma_ranges(struct ixp4xx_pci *p)440{441	struct device *dev = p->dev;442	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(p);443	struct resource_entry *win;444	struct resource *res;445	phys_addr_t addr;446	u32 ahbmembase;447 448	win = resource_list_first_type(&bridge->dma_ranges, IORESOURCE_MEM);449	if (win) {450		res = win->res;451		addr = res->start - win->offset;452 453		if (resource_size(res) != SZ_64M) {454			dev_err(dev, "DMA memory range is not 64MB\n");455			return -EINVAL;456		}457 458		dev_dbg(dev, "DMA MEM BASE: %pa\n", &addr);459		/*460		 * 4 PCI-to-AHB windows of 16 MB each, write the 8 high bits461		 * into each byte of the PCI_AHBMEMBASE register.462		 */463		ahbmembase = ixp4xx_pci_addr_to_64mconf(addr);464		/* Commit AHB membase */465		ixp4xx_writel(p, IXP4XX_PCI_AHBMEMBASE, ahbmembase);466	} else {467		dev_err(dev, "no DMA memory range defined\n");468	}469 470	return 0;471}472 473/* Only used to get context for abort handling */474static struct ixp4xx_pci *ixp4xx_pci_abort_singleton;475 476static int ixp4xx_pci_abort_handler(unsigned long addr, unsigned int fsr,477				    struct pt_regs *regs)478{479	struct ixp4xx_pci *p = ixp4xx_pci_abort_singleton;480	u32 isr, status;481	int ret;482 483	isr = ixp4xx_readl(p, IXP4XX_PCI_ISR);484	ret = ixp4xx_crp_read_config(p, PCI_STATUS, 2, &status);485	if (ret) {486		dev_err(p->dev, "unable to read abort status\n");487		return -EINVAL;488	}489 490	dev_err(p->dev,491		"PCI: abort_handler addr = %#lx, isr = %#x, status = %#x\n",492		addr, isr, status);493 494	/* Make sure the Master Abort bit is reset */495	ixp4xx_writel(p, IXP4XX_PCI_ISR, IXP4XX_PCI_ISR_PFE);496	status |= PCI_STATUS_REC_MASTER_ABORT;497	ret = ixp4xx_crp_write_config(p, PCI_STATUS, 2, status);498	if (ret)499		dev_err(p->dev, "unable to clear abort status bit\n");500 501	/*502	 * If it was an imprecise abort, then we need to correct the503	 * return address to be _after_ the instruction.504	 */505	if (fsr & (1 << 10)) {506		dev_err(p->dev, "imprecise abort\n");507		regs->ARM_pc += 4;508	}509 510	return 0;511}512 513static int __init ixp4xx_pci_probe(struct platform_device *pdev)514{515	struct device *dev = &pdev->dev;516	struct device_node *np = dev->of_node;517	struct ixp4xx_pci *p;518	struct pci_host_bridge *host;519	int ret;520	u32 val;521	phys_addr_t addr;522	u32 basereg[4] = {523		PCI_BASE_ADDRESS_0,524		PCI_BASE_ADDRESS_1,525		PCI_BASE_ADDRESS_2,526		PCI_BASE_ADDRESS_3,527	};528	int i;529 530	host = devm_pci_alloc_host_bridge(dev, sizeof(*p));531	if (!host)532		return -ENOMEM;533 534	host->ops = &ixp4xx_pci_ops;535	p = pci_host_bridge_priv(host);536	host->sysdata = p;537	p->dev = dev;538	dev_set_drvdata(dev, p);539 540	/*541	 * Set up quirk for erratic behaviour in the 42x variant542	 * when accessing config space.543	 */544	if (of_device_is_compatible(np, "intel,ixp42x-pci")) {545		p->errata_hammer = true;546		dev_info(dev, "activate hammering errata\n");547	}548 549	p->base = devm_platform_ioremap_resource(pdev, 0);550	if (IS_ERR(p->base))551		return PTR_ERR(p->base);552 553	val = ixp4xx_readl(p, IXP4XX_PCI_CSR);554	p->host_mode = !!(val & IXP4XX_PCI_CSR_HOST);555	dev_info(dev, "controller is in %s mode\n",556		 p->host_mode ? "host" : "option");557 558	/* Hook in our fault handler for PCI errors */559	ixp4xx_pci_abort_singleton = p;560	hook_fault_code(16+6, ixp4xx_pci_abort_handler, SIGBUS, 0,561			"imprecise external abort");562 563	ret = ixp4xx_pci_parse_map_ranges(p);564	if (ret)565		return ret;566 567	ret = ixp4xx_pci_parse_map_dma_ranges(p);568	if (ret)569		return ret;570 571	/* This is only configured in host mode */572	if (p->host_mode) {573		addr = __pa(PAGE_OFFSET);574		/* This is a noop (0x00) but explains what is going on */575		addr |= PCI_BASE_ADDRESS_SPACE_MEMORY;576 577		for (i = 0; i < 4; i++) {578			/* Write this directly into the config space */579			ret = ixp4xx_crp_write_config(p, basereg[i], 4, addr);580			if (ret)581				dev_err(dev, "failed to set up PCI_BASE_ADDRESS_%d\n", i);582			else583				dev_info(dev, "set PCI_BASE_ADDR_%d to %pa\n", i, &addr);584			addr += SZ_16M;585		}586 587		/*588		 * Enable CSR window at 64 MiB to allow PCI masters to continue589		 * prefetching past the 64 MiB boundary, if all AHB to PCI590		 * windows are consecutive.591		 */592		ret = ixp4xx_crp_write_config(p, PCI_BASE_ADDRESS_4, 4, addr);593		if (ret)594			dev_err(dev, "failed to set up PCI_BASE_ADDRESS_4\n");595		else596			dev_info(dev, "set PCI_BASE_ADDR_4 to %pa\n", &addr);597 598		/*599		 * Put the IO memory window at the very end of physical memory600		 * at 0xfffffc00. This is when the system is trying to access IO601		 * memory over AHB.602		 */603		addr = 0xfffffc00;604		addr |= PCI_BASE_ADDRESS_SPACE_IO;605		ret = ixp4xx_crp_write_config(p, PCI_BASE_ADDRESS_5, 4, addr);606		if (ret)607			dev_err(dev, "failed to set up PCI_BASE_ADDRESS_5\n");608		else609			dev_info(dev, "set PCI_BASE_ADDR_5 to %pa\n", &addr);610 611		/*612		 * Retry timeout to 0x80613		 * Transfer ready timeout to 0xff614		 */615		ret = ixp4xx_crp_write_config(p, IXP4XX_PCI_RTOTTO, 4,616					      0x000080ff);617		if (ret)618			dev_err(dev, "failed to set up TRDY limit\n");619		else620			dev_info(dev, "set TRDY limit to 0x80ff\n");621	}622 623	/* Clear interrupts */624	val = IXP4XX_PCI_ISR_PSE | IXP4XX_PCI_ISR_PFE | IXP4XX_PCI_ISR_PPE | IXP4XX_PCI_ISR_AHBE;625	ixp4xx_writel(p, IXP4XX_PCI_ISR, val);626 627	/*628	 * Set Initialize Complete in PCI Control Register: allow IXP4XX to629	 * generate PCI configuration cycles. Specify that the AHB bus is630	 * operating in big-endian mode. Set up byte lane swapping between631	 * little-endian PCI and the big-endian AHB bus.632	 */633	val = IXP4XX_PCI_CSR_IC | IXP4XX_PCI_CSR_ABE;634	if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))635		val |= (IXP4XX_PCI_CSR_PDS | IXP4XX_PCI_CSR_ADS);636	ixp4xx_writel(p, IXP4XX_PCI_CSR, val);637 638	ret = ixp4xx_crp_write_config(p, PCI_COMMAND, 2, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);639	if (ret)640		dev_err(dev, "unable to initialize master and command memory\n");641	else642		dev_info(dev, "initialized as master\n");643 644	pci_host_probe(host);645 646	return 0;647}648 649static const struct of_device_id ixp4xx_pci_of_match[] = {650	{651		.compatible = "intel,ixp42x-pci",652	},653	{654		.compatible = "intel,ixp43x-pci",655	},656	{},657};658 659/*660 * This driver needs to be a builtin module with suppressed bind661 * attributes since the probe() is initializing a hard exception662 * handler and this can only be done from __init-tagged code663 * sections. This module cannot be removed and inserted at all.664 */665static struct platform_driver ixp4xx_pci_driver = {666	.driver = {667		.name = "ixp4xx-pci",668		.suppress_bind_attrs = true,669		.of_match_table = ixp4xx_pci_of_match,670	},671};672builtin_platform_driver_probe(ixp4xx_pci_driver, ixp4xx_pci_probe);673