/*
* $Id: pcibios.c,v 1.1 2001/08/24 12:38:19 dwmw2 Exp $
*
* arch/sh/kernel/pcibios.c
*
* Copyright (C) 2002 STMicroelectronics Limited
* Author : David J. McKay
*
* Copyright (C) 2004 Richard Curnow, SuperH UK Limited
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
* This is GPL'd.
*
* Provided here are generic versions of:
* pcibios_update_resource()
* pcibios_align_resource()
* pcibios_enable_device()
* pcibios_set_master()
* pcibios_update_irq()
*
* These functions are collected here to reduce duplication of common
* code amongst the many platform-specific PCI support code files.
*
* Platform-specific files are expected to provide:
* pcibios_fixup_bus()
* pcibios_init()
* pcibios_setup()
* pcibios_fixup_pbus_ranges()
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/init.h>
void
pcibios_update_resource(struct pci_dev *dev, struct resource *root,
struct resource *res, int resource)
{
u32 new, check;
int reg;
new = res->start | (res->flags & PCI_REGION_FLAG_MASK);
if (resource < 6) {
reg = PCI_BASE_ADDRESS_0 + 4*resource;
} else if (resource == PCI_ROM_RESOURCE) {
res->flags |= IORESOURCE_ROM_ENABLE;
new |= PCI_ROM_ADDRESS_ENABLE;
reg = dev->rom_base_reg;
} else {
/* Somebody might have asked allocation of a non-standard resource */
return;
}
pci_write_config_dword(dev, reg, new);
pci_read_config_dword(dev, reg, &check);
if ((new ^ check) & ((new & PCI_BASE_ADDRESS_SPACE_IO) ? PCI_BASE_ADDRESS_IO_MASK : PCI_BASE_ADDRESS_MEM_MASK)) {
printk(KERN_ERR "PCI: Error while updating region "
"%s/%d (%08x != %08x)\n", pci_name(dev), resource,
new, check);
}
}
/*
* We need to avoid collisions with `mirrored' VGA ports
* and other strange ISA hardware, so we always want the
* addresses to be allocated in the 0x000-0x0ff region
* modulo 0x400.
*/
void pcibios_align_resource(void *data, struct resource *res,
resource_size_t size, resource_size_t align)
{
if (res->flags & IORESOURCE_IO) {
resource_size_t start = res->start;
if (start & 0x300) {
start = (start + 0x3ff) & ~0x3ff;
res->start = start;
}
}
}
static void pcibios_enable_bridge(struct pci_dev *dev)
{
struct pci_bus *bus = dev->subordinate;
u16 cmd, old_cmd;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
old_cmd = cmd;
if (bus->resource[0]->flags & IORESOURCE_IO) {
cmd |= PCI_COMMAND_IO;
}
if ((bus->resource[1]->flags & IORESOURCE_MEM) ||
(bus->resource[2]->flags & IORESOURCE_PREFETCH)) {
cmd |= PCI_COMMAND_MEMORY;
}
if (cmd != old_cmd) {
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
printk("PCI bridge %s, command register -> %04x\n",
pci_name(dev), cmd);
}
int pcibios_enable_device(struct pci_dev *dev, int mask)
{
u16 cmd, old_cmd;
int idx;
struct resource *r;
if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
pcibios_enable_bridge(dev);
}
pci_read_config_word(dev, PCI_COMMAND, &cmd);
old_cmd = cmd;
for(idx=0; idx<6; idx++) {
if (!(mask & (1 << idx)))
continue;
r = &dev->resource[idx];
if (!r->start && r->end) {
printk(KERN_ERR "PCI: Device %s not available because of resource collisions\n", pci_name(dev));
return -EINVAL;
}
if (r->flags & IORESOURCE_IO)
cmd |= PCI_COMMAND_IO;
if (r->flags & IORESOURCE_MEM)
cmd |= PCI_COMMAND_MEMORY;
}
if (dev->resource[PCI_ROM_RESOURCE].start)
cmd |= PCI_COMMAND_MEMORY;
if (cmd != old_cmd) {
printk(KERN_INFO "PCI: Enabling device %s (%04x -> %04x)\n", pci_name(dev), old_cmd, cmd);
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
return 0;
}
/*
* If we set up a device for bus mastering, we need to check and set
* the latency timer as it may not be properly set.
*/
unsigned int pcibios_max_latency = 255;
void pcibios_set_master(struct pci_dev *dev)
{
u8 lat;
pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
if (lat < 16)
lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
else if (lat > pcibios_max_latency)
lat = pcibios_max_latency;
else
return;
printk(KERN_INFO "PCI: Setting latency timer of device %s to %d\n", pci_name(dev), lat);
pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
}
void __init pcibios_update_irq(struct pci_dev *dev, int irq)
{
pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
}
