linux/arch/sh/drivers/pci/pci.c

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/*
* arch/sh/drivers/pci/pci.c
*
* Copyright (c) 2002 M. R. Brown <mrbrown@linux-sh.org>
* Copyright (c) 2004 - 2006 Paul Mundt <lethal@linux-sh.org>
*
* These functions are collected here to reduce duplication of common
* code amongst the many platform-specific PCI support code files.
*
* These routines require the following board-specific routines:
* void pcibios_fixup_irqs();
*
* See include/asm-sh/pci.h for more information.
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <asm/io.h>
static int __init pcibios_init(void)
{
struct pci_channel *p;
struct pci_bus *bus;
int busno;
#ifdef CONFIG_PCI_AUTO
/* assign resources */
busno = 0;
for (p = board_pci_channels; p->pci_ops != NULL; p++)
busno = pciauto_assign_resources(busno, p) + 1;
#endif
/* scan the buses */
busno = 0;
for (p= board_pci_channels; p->pci_ops != NULL; p++) {
bus = pci_scan_bus(busno, p->pci_ops, p);
busno = bus->subordinate+1;
}
/* board-specific fixups */
pcibios_fixup_irqs();
return 0;
}
subsys_initcall(pcibios_init);
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);
}
}
void pcibios_align_resource(void *data, struct resource *res,
resource_size_t size, resource_size_t align)
__attribute__ ((weak));
/*
* 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;
}
}
}
int pcibios_enable_device(struct pci_dev *dev, int mask)
{
u16 cmd, old_cmd;
int idx;
struct resource *r;
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);
}
void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
{
unsigned long start = pci_resource_start(dev, bar);
unsigned long len = pci_resource_len(dev, bar);
unsigned long flags = pci_resource_flags(dev, bar);
if (!len || !start)
return NULL;
if (maxlen && len > maxlen)
len = maxlen;
/*
* Presently the IORESOURCE_MEM case is a bit special, most
* SH7751 style PCI controllers have PCI memory at a fixed
* location in the address space where no remapping is desired
* (traditionally at 0xfd000000). Once this changes, the
* IORESOURCE_MEM case will have to switch to using ioremap() and
* more care will have to be taken to inhibit page table mapping
* for legacy cores.
*
* For now everything wraps to ioport_map(), since boards that
* have PCI will be able to check the address range properly on
* their own.
* -- PFM.
*/
if (flags & (IORESOURCE_IO | IORESOURCE_MEM))
return ioport_map(start, len);
return NULL;
}
void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
{
iounmap(addr);
}
EXPORT_SYMBOL(pci_iomap);
EXPORT_SYMBOL(pci_iounmap);