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linux/arch/x86_64/kernel/k8.c
Andi Kleen a32073bffc [PATCH] x86_64: Clean and enhance up K8 northbridge access code
- Factor out the duplicated access/cache code into a single file
   * Shared between i386/x86-64.
 - Share flush code between AGP and IOMMU
   * Fix a bug: AGP didn't wait for end of flush before
 - Drop 8 northbridges limit and allocate dynamically
 - Add lock to serialize AGP and IOMMU GART flushes
 - Add PCI ID for next AMD northbridge
 - Random related cleanups

The old K8 NUMA discovery code is unchanged. New systems
should all use SRAT for this.

Cc: "Navin Boppuri" <navin.boppuri@newisys.com>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 10:48:15 -07:00

119 lines
2.7 KiB
C

/*
* Shared support code for AMD K8 northbridges and derivates.
* Copyright 2006 Andi Kleen, SUSE Labs. Subject to GPLv2.
*/
#include <linux/gfp.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <asm/k8.h>
int num_k8_northbridges;
EXPORT_SYMBOL(num_k8_northbridges);
static u32 *flush_words;
struct pci_device_id k8_nb_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, 0x1103) },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, 0x1203) },
{}
};
EXPORT_SYMBOL(k8_nb_ids);
struct pci_dev **k8_northbridges;
EXPORT_SYMBOL(k8_northbridges);
static struct pci_dev *next_k8_northbridge(struct pci_dev *dev)
{
do {
dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
if (!dev)
break;
} while (!pci_match_id(&k8_nb_ids[0], dev));
return dev;
}
int cache_k8_northbridges(void)
{
int i;
struct pci_dev *dev;
if (num_k8_northbridges)
return 0;
num_k8_northbridges = 0;
dev = NULL;
while ((dev = next_k8_northbridge(dev)) != NULL)
num_k8_northbridges++;
k8_northbridges = kmalloc((num_k8_northbridges + 1) * sizeof(void *),
GFP_KERNEL);
if (!k8_northbridges)
return -ENOMEM;
flush_words = kmalloc(num_k8_northbridges * sizeof(u32), GFP_KERNEL);
if (!flush_words) {
kfree(k8_northbridges);
return -ENOMEM;
}
dev = NULL;
i = 0;
while ((dev = next_k8_northbridge(dev)) != NULL) {
k8_northbridges[i++] = dev;
pci_read_config_dword(dev, 0x9c, &flush_words[i]);
}
k8_northbridges[i] = NULL;
return 0;
}
EXPORT_SYMBOL_GPL(cache_k8_northbridges);
/* Ignores subdevice/subvendor but as far as I can figure out
they're useless anyways */
int __init early_is_k8_nb(u32 device)
{
struct pci_device_id *id;
u32 vendor = device & 0xffff;
device >>= 16;
for (id = k8_nb_ids; id->vendor; id++)
if (vendor == id->vendor && device == id->device)
return 1;
return 0;
}
void k8_flush_garts(void)
{
int flushed, i;
unsigned long flags;
static DEFINE_SPINLOCK(gart_lock);
/* Avoid races between AGP and IOMMU. In theory it's not needed
but I'm not sure if the hardware won't lose flush requests
when another is pending. This whole thing is so expensive anyways
that it doesn't matter to serialize more. -AK */
spin_lock_irqsave(&gart_lock, flags);
flushed = 0;
for (i = 0; i < num_k8_northbridges; i++) {
pci_write_config_dword(k8_northbridges[i], 0x9c,
flush_words[i]|1);
flushed++;
}
for (i = 0; i < num_k8_northbridges; i++) {
u32 w;
/* Make sure the hardware actually executed the flush*/
for (;;) {
pci_read_config_dword(k8_northbridges[i],
0x9c, &w);
if (!(w & 1))
break;
cpu_relax();
}
}
spin_unlock_irqrestore(&gart_lock, flags);
if (!flushed)
printk("nothing to flush?\n");
}
EXPORT_SYMBOL_GPL(k8_flush_garts);