WSL2-Linux-Kernel/arch/arm/plat-iop/pci.c

248 строки
6.2 KiB
C

/*
* arch/arm/plat-iop/pci.c
*
* PCI support for the Intel IOP32X and IOP33X processors
*
* Author: Rory Bolt <rorybolt@pacbell.net>
* Copyright (C) 2002 Rory Bolt
*
* 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/kernel.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/hardware.h>
#include <asm/mach/pci.h>
#include <asm/hardware/iop3xx.h>
// #define DEBUG
#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...) do { } while (0)
#endif
/*
* This routine builds either a type0 or type1 configuration command. If the
* bus is on the 803xx then a type0 made, else a type1 is created.
*/
static u32 iop3xx_cfg_address(struct pci_bus *bus, int devfn, int where)
{
struct pci_sys_data *sys = bus->sysdata;
u32 addr;
if (sys->busnr == bus->number)
addr = 1 << (PCI_SLOT(devfn) + 16) | (PCI_SLOT(devfn) << 11);
else
addr = bus->number << 16 | PCI_SLOT(devfn) << 11 | 1;
addr |= PCI_FUNC(devfn) << 8 | (where & ~3);
return addr;
}
/*
* This routine checks the status of the last configuration cycle. If an error
* was detected it returns a 1, else it returns a 0. The errors being checked
* are parity, master abort, target abort (master and target). These types of
* errors occure during a config cycle where there is no device, like during
* the discovery stage.
*/
static int iop3xx_pci_status(void)
{
unsigned int status;
int ret = 0;
/*
* Check the status registers.
*/
status = *IOP3XX_ATUSR;
if (status & 0xf900) {
DBG("\t\t\tPCI: P0 - status = 0x%08x\n", status);
*IOP3XX_ATUSR = status & 0xf900;
ret = 1;
}
status = *IOP3XX_ATUISR;
if (status & 0x679f) {
DBG("\t\t\tPCI: P1 - status = 0x%08x\n", status);
*IOP3XX_ATUISR = status & 0x679f;
ret = 1;
}
return ret;
}
/*
* Simply write the address register and read the configuration
* data. Note that the 4 nop's ensure that we are able to handle
* a delayed abort (in theory.)
*/
static inline u32 iop3xx_read(unsigned long addr)
{
u32 val;
__asm__ __volatile__(
"str %1, [%2]\n\t"
"ldr %0, [%3]\n\t"
"nop\n\t"
"nop\n\t"
"nop\n\t"
"nop\n\t"
: "=r" (val)
: "r" (addr), "r" (IOP3XX_OCCAR), "r" (IOP3XX_OCCDR));
return val;
}
/*
* The read routines must check the error status of the last configuration
* cycle. If there was an error, the routine returns all hex f's.
*/
static int
iop3xx_read_config(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 *value)
{
unsigned long addr = iop3xx_cfg_address(bus, devfn, where);
u32 val = iop3xx_read(addr) >> ((where & 3) * 8);
if (iop3xx_pci_status())
val = 0xffffffff;
*value = val;
return PCIBIOS_SUCCESSFUL;
}
static int
iop3xx_write_config(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 value)
{
unsigned long addr = iop3xx_cfg_address(bus, devfn, where);
u32 val;
if (size != 4) {
val = iop3xx_read(addr);
if (iop3xx_pci_status())
return PCIBIOS_SUCCESSFUL;
where = (where & 3) * 8;
if (size == 1)
val &= ~(0xff << where);
else
val &= ~(0xffff << where);
*IOP3XX_OCCDR = val | value << where;
} else {
asm volatile(
"str %1, [%2]\n\t"
"str %0, [%3]\n\t"
"nop\n\t"
"nop\n\t"
"nop\n\t"
"nop\n\t"
:
: "r" (value), "r" (addr),
"r" (IOP3XX_OCCAR), "r" (IOP3XX_OCCDR));
}
return PCIBIOS_SUCCESSFUL;
}
static struct pci_ops iop3xx_ops = {
.read = iop3xx_read_config,
.write = iop3xx_write_config,
};
/*
* When a PCI device does not exist during config cycles, the 80200 gets a
* bus error instead of returning 0xffffffff. This handler simply returns.
*/
static int
iop3xx_pci_abort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
{
DBG("PCI abort: address = 0x%08lx fsr = 0x%03x PC = 0x%08lx LR = 0x%08lx\n",
addr, fsr, regs->ARM_pc, regs->ARM_lr);
/*
* 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 iop3xx_pci_setup(int nr, struct pci_sys_data *sys)
{
struct resource *res;
if (nr != 0)
return 0;
res = kzalloc(2 * sizeof(struct resource), GFP_KERNEL);
if (!res)
panic("PCI: unable to alloc resources");
res[0].start = IOP3XX_PCI_LOWER_IO_VA;
res[0].end = IOP3XX_PCI_LOWER_IO_VA + IOP3XX_PCI_IO_WINDOW_SIZE - 1;
res[0].name = "IOP3XX PCI I/O Space";
res[0].flags = IORESOURCE_IO;
request_resource(&ioport_resource, &res[0]);
res[1].start = IOP3XX_PCI_LOWER_MEM_PA;
res[1].end = IOP3XX_PCI_LOWER_MEM_PA + IOP3XX_PCI_MEM_WINDOW_SIZE - 1;
res[1].name = "IOP3XX PCI Memory Space";
res[1].flags = IORESOURCE_MEM;
request_resource(&iomem_resource, &res[1]);
sys->mem_offset = IOP3XX_PCI_LOWER_MEM_PA - IOP3XX_PCI_LOWER_MEM_BA;
sys->io_offset = IOP3XX_PCI_LOWER_IO_VA - IOP3XX_PCI_LOWER_IO_BA;
sys->resource[0] = &res[0];
sys->resource[1] = &res[1];
sys->resource[2] = NULL;
return 1;
}
struct pci_bus *iop3xx_pci_scan_bus(int nr, struct pci_sys_data *sys)
{
return pci_scan_bus(sys->busnr, &iop3xx_ops, sys);
}
void iop3xx_pci_preinit(void)
{
DBG("PCI: Intel 803xx PCI init code.\n");
DBG("ATU: IOP3XX_ATUCMD=0x%04x\n", *IOP3XX_ATUCMD);
DBG("ATU: IOP3XX_OMWTVR0=0x%04x, IOP3XX_OIOWTVR=0x%04x\n",
*IOP3XX_OMWTVR0,
*IOP3XX_OIOWTVR);
DBG("ATU: IOP3XX_ATUCR=0x%08x\n", *IOP3XX_ATUCR);
DBG("ATU: IOP3XX_IABAR0=0x%08x IOP3XX_IALR0=0x%08x IOP3XX_IATVR0=%08x\n",
*IOP3XX_IABAR0, *IOP3XX_IALR0, *IOP3XX_IATVR0);
DBG("ATU: IOP3XX_OMWTVR0=0x%08x\n", *IOP3XX_OMWTVR0);
DBG("ATU: IOP3XX_IABAR1=0x%08x IOP3XX_IALR1=0x%08x\n",
*IOP3XX_IABAR1, *IOP3XX_IALR1);
DBG("ATU: IOP3XX_ERBAR=0x%08x IOP3XX_ERLR=0x%08x IOP3XX_ERTVR=%08x\n",
*IOP3XX_ERBAR, *IOP3XX_ERLR, *IOP3XX_ERTVR);
DBG("ATU: IOP3XX_IABAR2=0x%08x IOP3XX_IALR2=0x%08x IOP3XX_IATVR2=%08x\n",
*IOP3XX_IABAR2, *IOP3XX_IALR2, *IOP3XX_IATVR2);
DBG("ATU: IOP3XX_IABAR3=0x%08x IOP3XX_IALR3=0x%08x IOP3XX_IATVR3=%08x\n",
*IOP3XX_IABAR3, *IOP3XX_IALR3, *IOP3XX_IATVR3);
hook_fault_code(16+6, iop3xx_pci_abort, SIGBUS, "imprecise external abort");
}