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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/pci/controller/pci-ixp4xx.c | |
parent | Initial commit. (diff) | |
download | linux-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.c | 671 |
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); |