diff options
Diffstat (limited to 'arch/arm/mach-ixp2000/pci.c')
| -rw-r--r-- | arch/arm/mach-ixp2000/pci.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/arch/arm/mach-ixp2000/pci.c b/arch/arm/mach-ixp2000/pci.c new file mode 100644 index 0000000..831f8ff --- /dev/null +++ b/arch/arm/mach-ixp2000/pci.c @@ -0,0 +1,235 @@ +/* + * arch/arm/mach-ixp2000/pci.c + * + * PCI routines for IXDP2400/IXDP2800 boards + * + * Original Author: Naeem Afzal <naeem.m.afzal@intel.com> + * Maintained by: Deepak Saxena <dsaxena@plexity.net> + * + * Copyright 2002 Intel Corp. + * 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 as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#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 <asm/io.h> +#include <asm/irq.h> +#include <asm/system.h> +#include <asm/mach-types.h> +#include <asm/hardware.h> + +#include <asm/mach/pci.h> + +static int pci_master_aborts = 0; + +static int clear_master_aborts(void); + +static u32 * +ixp2000_pci_config_addr(unsigned int bus_nr, unsigned int devfn, int where) +{ + u32 *paddress; + + if (PCI_SLOT(devfn) > 7) + return 0; + + /* Must be dword aligned */ + where &= ~3; + + /* + * For top bus, generate type 0, else type 1 + */ + if (!bus_nr) { + /* only bits[23:16] are used for IDSEL */ + paddress = (u32 *) (IXP2000_PCI_CFG0_VIRT_BASE + | (1 << (PCI_SLOT(devfn) + 16)) + | (PCI_FUNC(devfn) << 8) | where); + } else { + paddress = (u32 *) (IXP2000_PCI_CFG1_VIRT_BASE + | (bus_nr << 16) + | (PCI_SLOT(devfn) << 11) + | (PCI_FUNC(devfn) << 8) | where); + } + + return paddress; +} + +/* + * 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, +}; + + +int ixp2000_pci_read_config(struct pci_bus *bus, unsigned int devfn, int where, + int size, u32 *value) +{ + u32 n; + u32 *addr; + + n = where % 4; + + addr = ixp2000_pci_config_addr(bus->number, devfn, where); + if (!addr) + return PCIBIOS_DEVICE_NOT_FOUND; + + pci_master_aborts = 0; + *value = (*addr >> (8*n)) & bytemask[size]; + if (pci_master_aborts) { + pci_master_aborts = 0; + *value = 0xffffffff; + return PCIBIOS_DEVICE_NOT_FOUND; + } + + return PCIBIOS_SUCCESSFUL; +} + +/* + * We don't do error checks by callling clear_master_aborts() b/c the + * assumption is that the caller did a read first to make sure a device + * exists. + */ +int ixp2000_pci_write_config(struct pci_bus *bus, unsigned int devfn, int where, + int size, u32 value) +{ + u32 mask; + u32 *addr; + u32 temp; + + mask = ~(bytemask[size] << ((where % 0x4) * 8)); + addr = ixp2000_pci_config_addr(bus->number, devfn, where); + if (!addr) + return PCIBIOS_DEVICE_NOT_FOUND; + temp = (u32) (value) << ((where % 0x4) * 8); + *addr = (*addr & mask) | temp; + + clear_master_aborts(); + + return PCIBIOS_SUCCESSFUL; +} + + +static struct pci_ops ixp2000_pci_ops = { + .read = ixp2000_pci_read_config, + .write = ixp2000_pci_write_config +}; + +struct pci_bus *ixp2000_pci_scan_bus(int nr, struct pci_sys_data *sysdata) +{ + return pci_scan_bus(sysdata->busnr, &ixp2000_pci_ops, sysdata); +} + + +int ixp2000_pci_abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs) +{ + + volatile u32 temp; + unsigned long flags; + + pci_master_aborts = 1; + + local_irq_save(flags); + temp = *(IXP2000_PCI_CONTROL); + if (temp & ((1 << 8) | (1 << 5))) { + ixp2000_reg_write(IXP2000_PCI_CONTROL, temp); + } + + temp = *(IXP2000_PCI_CMDSTAT); + if (temp & (1 << 29)) { + while (temp & (1 << 29)) { + ixp2000_reg_write(IXP2000_PCI_CMDSTAT, temp); + temp = *(IXP2000_PCI_CMDSTAT); + } + } + local_irq_restore(flags); + + /* + * 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; +} + +int +clear_master_aborts(void) +{ + volatile u32 temp; + unsigned long flags; + + local_irq_save(flags); + temp = *(IXP2000_PCI_CONTROL); + if (temp & ((1 << 8) | (1 << 5))) { + ixp2000_reg_write(IXP2000_PCI_CONTROL, temp); + } + + temp = *(IXP2000_PCI_CMDSTAT); + if (temp & (1 << 29)) { + while (temp & (1 << 29)) { + ixp2000_reg_write(IXP2000_PCI_CMDSTAT, temp); + temp = *(IXP2000_PCI_CMDSTAT); + } + } + local_irq_restore(flags); + + return 0; +} + +void __init +ixp2000_pci_preinit(void) +{ + hook_fault_code(16+6, ixp2000_pci_abort_handler, SIGBUS, + "PCI config cycle to non-existent device"); +} + + +/* + * IXP2000 systems often have large resource requirements, so we just + * use our own resource space. + */ +static struct resource ixp2000_pci_mem_space = { + .start = 0x00000000, + .end = 0xffffffff, + .flags = IORESOURCE_MEM, + .name = "PCI Mem Space" +}; + +static struct resource ixp2000_pci_io_space = { + .start = 0x00000000, + .end = 0xffffffff, + .flags = IORESOURCE_IO, + .name = "PCI I/O Space" +}; + +int ixp2000_pci_setup(int nr, struct pci_sys_data *sys) +{ + if (nr >= 1) + return 0; + + sys->resource[0] = &ixp2000_pci_io_space; + sys->resource[1] = &ixp2000_pci_mem_space; + sys->resource[2] = NULL; + + return 1; +} + |