diff options
Diffstat (limited to 'kernel/arch/arm/mach-ixp4xx/common-pci.c')
| -rw-r--r-- | kernel/arch/arm/mach-ixp4xx/common-pci.c | 455 |
1 files changed, 455 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-ixp4xx/common-pci.c b/kernel/arch/arm/mach-ixp4xx/common-pci.c new file mode 100644 index 000000000..4977296f0 --- /dev/null +++ b/kernel/arch/arm/mach-ixp4xx/common-pci.c @@ -0,0 +1,455 @@ +/* + * arch/arm/mach-ixp4xx/common-pci.c + * + * IXP4XX PCI routines for all platforms + * + * Maintainer: Deepak Saxena <dsaxena@plexity.net> + * + * Copyright (C) 2002 Intel Corporation. + * Copyright (C) 2003 Greg Ungerer <gerg@snapgear.com> + * Copyright (C) 2003-2004 MontaVista Software, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/pci.h> +#include <linux/interrupt.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/ioport.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/io.h> +#include <linux/export.h> +#include <asm/dma-mapping.h> + +#include <asm/cputype.h> +#include <asm/irq.h> +#include <asm/sizes.h> +#include <asm/mach/pci.h> +#include <mach/hardware.h> + + +/* + * IXP4xx PCI read function is dependent on whether we are + * running A0 or B0 (AppleGate) silicon. + */ +int (*ixp4xx_pci_read)(u32 addr, u32 cmd, u32* data); + +/* + * Base address for PCI regsiter region + */ +unsigned long ixp4xx_pci_reg_base = 0; + +/* + * PCI cfg an I/O routines are done by programming a + * command/byte enable register, and then read/writing + * the data from a data regsiter. We need to ensure + * these transactions are atomic or we will end up + * with corrupt data on the bus or in a driver. + */ +static DEFINE_RAW_SPINLOCK(ixp4xx_pci_lock); + +/* + * Read from PCI config space + */ +static void crp_read(u32 ad_cbe, u32 *data) +{ + unsigned long flags; + raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags); + *PCI_CRP_AD_CBE = ad_cbe; + *data = *PCI_CRP_RDATA; + raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags); +} + +/* + * Write to PCI config space + */ +static void crp_write(u32 ad_cbe, u32 data) +{ + unsigned long flags; + raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags); + *PCI_CRP_AD_CBE = CRP_AD_CBE_WRITE | ad_cbe; + *PCI_CRP_WDATA = data; + raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags); +} + +static inline int check_master_abort(void) +{ + /* check Master Abort bit after access */ + unsigned long isr = *PCI_ISR; + + if (isr & PCI_ISR_PFE) { + /* make sure the Master Abort bit is reset */ + *PCI_ISR = PCI_ISR_PFE; + pr_debug("%s failed\n", __func__); + return 1; + } + + return 0; +} + +int ixp4xx_pci_read_errata(u32 addr, u32 cmd, u32* data) +{ + unsigned long flags; + int retval = 0; + int i; + + raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags); + + *PCI_NP_AD = addr; + + /* + * PCI workaround - only works if NP PCI space reads have + * no side effects!!! Read 8 times. last one will be good. + */ + for (i = 0; i < 8; i++) { + *PCI_NP_CBE = cmd; + *data = *PCI_NP_RDATA; + *data = *PCI_NP_RDATA; + } + + if(check_master_abort()) + retval = 1; + + raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags); + return retval; +} + +int ixp4xx_pci_read_no_errata(u32 addr, u32 cmd, u32* data) +{ + unsigned long flags; + int retval = 0; + + raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags); + + *PCI_NP_AD = addr; + + /* set up and execute the read */ + *PCI_NP_CBE = cmd; + + /* the result of the read is now in NP_RDATA */ + *data = *PCI_NP_RDATA; + + if(check_master_abort()) + retval = 1; + + raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags); + return retval; +} + +int ixp4xx_pci_write(u32 addr, u32 cmd, u32 data) +{ + unsigned long flags; + int retval = 0; + + raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags); + + *PCI_NP_AD = addr; + + /* set up the write */ + *PCI_NP_CBE = cmd; + + /* execute the write by writing to NP_WDATA */ + *PCI_NP_WDATA = data; + + if(check_master_abort()) + retval = 1; + + raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags); + return retval; +} + +static u32 ixp4xx_config_addr(u8 bus_num, u16 devfn, int where) +{ + u32 addr; + if (!bus_num) { + /* type 0 */ + addr = BIT(32-PCI_SLOT(devfn)) | ((PCI_FUNC(devfn)) << 8) | + (where & ~3); + } else { + /* type 1 */ + addr = (bus_num << 16) | ((PCI_SLOT(devfn)) << 11) | + ((PCI_FUNC(devfn)) << 8) | (where & ~3) | 1; + } + return addr; +} + +/* + * Mask table, bits to mask for quantity of size 1, 2 or 4 bytes. + * 0 and 3 are not valid indexes... + */ +static u32 bytemask[] = { + /*0*/ 0, + /*1*/ 0xff, + /*2*/ 0xffff, + /*3*/ 0, + /*4*/ 0xffffffff, +}; + +static u32 local_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 local_read_config(int where, int size, u32 *value) +{ + u32 n, data; + pr_debug("local_read_config from %d size %d\n", where, size); + n = where % 4; + crp_read(where & ~3, &data); + *value = (data >> (8*n)) & bytemask[size]; + pr_debug("local_read_config read %#x\n", *value); + return PCIBIOS_SUCCESSFUL; +} + +static int local_write_config(int where, int size, u32 value) +{ + u32 n, byte_enables, data; + pr_debug("local_write_config %#x to %d size %d\n", value, where, size); + n = where % 4; + byte_enables = local_byte_lane_enable_bits(n, size); + if (byte_enables == 0xffffffff) + return PCIBIOS_BAD_REGISTER_NUMBER; + data = value << (8*n); + crp_write((where & ~3) | byte_enables, data); + return PCIBIOS_SUCCESSFUL; +} + +static u32 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) +{ + u32 n, byte_enables, addr, data; + u8 bus_num = bus->number; + + pr_debug("read_config from %d size %d dev %d:%d:%d\n", where, size, + bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn)); + + *value = 0xffffffff; + n = where % 4; + byte_enables = byte_lane_enable_bits(n, size); + if (byte_enables == 0xffffffff) + return PCIBIOS_BAD_REGISTER_NUMBER; + + addr = ixp4xx_config_addr(bus_num, devfn, where); + if (ixp4xx_pci_read(addr, byte_enables | NP_CMD_CONFIGREAD, &data)) + return PCIBIOS_DEVICE_NOT_FOUND; + + *value = (data >> (8*n)) & bytemask[size]; + pr_debug("read_config_byte read %#x\n", *value); + return PCIBIOS_SUCCESSFUL; +} + +static int ixp4xx_pci_write_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value) +{ + u32 n, byte_enables, addr, data; + u8 bus_num = bus->number; + + pr_debug("write_config_byte %#x to %d size %d dev %d:%d:%d\n", value, where, + size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn)); + + n = where % 4; + byte_enables = byte_lane_enable_bits(n, size); + if (byte_enables == 0xffffffff) + return PCIBIOS_BAD_REGISTER_NUMBER; + + addr = ixp4xx_config_addr(bus_num, devfn, where); + data = value << (8*n); + if (ixp4xx_pci_write(addr, byte_enables | NP_CMD_CONFIGWRITE, data)) + return PCIBIOS_DEVICE_NOT_FOUND; + + return PCIBIOS_SUCCESSFUL; +} + +struct pci_ops ixp4xx_ops = { + .read = ixp4xx_pci_read_config, + .write = ixp4xx_pci_write_config, +}; + +/* + * PCI abort handler + */ +static int abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs) +{ + u32 isr, status; + + isr = *PCI_ISR; + local_read_config(PCI_STATUS, 2, &status); + pr_debug("PCI: abort_handler addr = %#lx, isr = %#x, " + "status = %#x\n", addr, isr, status); + + /* make sure the Master Abort bit is reset */ + *PCI_ISR = PCI_ISR_PFE; + status |= PCI_STATUS_REC_MASTER_ABORT; + local_write_config(PCI_STATUS, 2, status); + + /* + * If it was an imprecise abort, then we need to correct the + * return address to be _after_ the instruction. + */ + if (fsr & (1 << 10)) + regs->ARM_pc += 4; + + return 0; +} + +void __init ixp4xx_pci_preinit(void) +{ + unsigned long cpuid = read_cpuid_id(); + +#ifdef CONFIG_IXP4XX_INDIRECT_PCI + pcibios_min_mem = 0x10000000; /* 1 GB of indirect PCI MMIO space */ +#else + pcibios_min_mem = 0x48000000; /* 64 MB of PCI MMIO space */ +#endif + /* + * Determine which PCI read method to use. + * Rev 0 IXP425 requires workaround. + */ + if (!(cpuid & 0xf) && cpu_is_ixp42x()) { + printk("PCI: IXP42x A0 silicon detected - " + "PCI Non-Prefetch Workaround Enabled\n"); + ixp4xx_pci_read = ixp4xx_pci_read_errata; + } else + ixp4xx_pci_read = ixp4xx_pci_read_no_errata; + + + /* hook in our fault handler for PCI errors */ + hook_fault_code(16+6, abort_handler, SIGBUS, 0, + "imprecise external abort"); + + pr_debug("setup PCI-AHB(inbound) and AHB-PCI(outbound) address mappings\n"); + + /* + * We use identity AHB->PCI address translation + * in the 0x48000000 to 0x4bffffff address space + */ + *PCI_PCIMEMBASE = 0x48494A4B; + + /* + * We also use identity PCI->AHB address translation + * in 4 16MB BARs that begin at the physical memory start + */ + *PCI_AHBMEMBASE = (PHYS_OFFSET & 0xFF000000) + + ((PHYS_OFFSET & 0xFF000000) >> 8) + + ((PHYS_OFFSET & 0xFF000000) >> 16) + + ((PHYS_OFFSET & 0xFF000000) >> 24) + + 0x00010203; + + if (*PCI_CSR & PCI_CSR_HOST) { + printk("PCI: IXP4xx is host\n"); + + pr_debug("setup BARs in controller\n"); + + /* + * We configure the PCI inbound memory windows to be + * 1:1 mapped to SDRAM + */ + local_write_config(PCI_BASE_ADDRESS_0, 4, PHYS_OFFSET); + local_write_config(PCI_BASE_ADDRESS_1, 4, PHYS_OFFSET + SZ_16M); + local_write_config(PCI_BASE_ADDRESS_2, 4, PHYS_OFFSET + SZ_32M); + local_write_config(PCI_BASE_ADDRESS_3, 4, + PHYS_OFFSET + SZ_32M + SZ_16M); + + /* + * Enable CSR window at 64 MiB to allow PCI masters + * to continue prefetching past 64 MiB boundary. + */ + local_write_config(PCI_BASE_ADDRESS_4, 4, PHYS_OFFSET + SZ_64M); + + /* + * Enable the IO window to be way up high, at 0xfffffc00 + */ + local_write_config(PCI_BASE_ADDRESS_5, 4, 0xfffffc01); + local_write_config(0x40, 4, 0x000080FF); /* No TRDY time limit */ + } else { + printk("PCI: IXP4xx is target - No bus scan performed\n"); + } + + printk("PCI: IXP4xx Using %s access for memory space\n", +#ifndef CONFIG_IXP4XX_INDIRECT_PCI + "direct" +#else + "indirect" +#endif + ); + + pr_debug("clear error bits in ISR\n"); + *PCI_ISR = PCI_ISR_PSE | PCI_ISR_PFE | PCI_ISR_PPE | PCI_ISR_AHBE; + + /* + * Set Initialize Complete in PCI Control Register: allow IXP4XX to + * respond to 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 + */ +#ifdef __ARMEB__ + *PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE | PCI_CSR_PDS | PCI_CSR_ADS; +#else + *PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE; +#endif + + pr_debug("DONE\n"); +} + +int ixp4xx_setup(int nr, struct pci_sys_data *sys) +{ + struct resource *res; + + if (nr >= 1) + return 0; + + res = kzalloc(sizeof(*res) * 2, GFP_KERNEL); + if (res == NULL) { + /* + * If we're out of memory this early, something is wrong, + * so we might as well catch it here. + */ + panic("PCI: unable to allocate resources?\n"); + } + + local_write_config(PCI_COMMAND, 2, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY); + + res[0].name = "PCI I/O Space"; + res[0].start = 0x00000000; + res[0].end = 0x0000ffff; + res[0].flags = IORESOURCE_IO; + + res[1].name = "PCI Memory Space"; + res[1].start = PCIBIOS_MIN_MEM; + res[1].end = PCIBIOS_MAX_MEM; + res[1].flags = IORESOURCE_MEM; + + request_resource(&ioport_resource, &res[0]); + request_resource(&iomem_resource, &res[1]); + + pci_add_resource_offset(&sys->resources, &res[0], sys->io_offset); + pci_add_resource_offset(&sys->resources, &res[1], sys->mem_offset); + + return 1; +} + +EXPORT_SYMBOL(ixp4xx_pci_read); +EXPORT_SYMBOL(ixp4xx_pci_write); |