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Diffstat (limited to 'arch/x86/pci/common.c')
-rw-r--r--arch/x86/pci/common.c20
1 files changed, 11 insertions, 9 deletions
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 1331fcf26143..d2552c68e94d 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -410,8 +410,6 @@ struct pci_bus * __devinit pcibios_scan_root(int busnum)
return bus;
}
-extern u8 pci_cache_line_size;
-
int __init pcibios_init(void)
{
struct cpuinfo_x86 *c = &boot_cpu_data;
@@ -422,15 +420,19 @@ int __init pcibios_init(void)
}
/*
- * Assume PCI cacheline size of 32 bytes for all x86s except K7/K8
- * and P4. It's also good for 386/486s (which actually have 16)
+ * Set PCI cacheline size to that of the CPU if the CPU has reported it.
+ * (For older CPUs that don't support cpuid, we se it to 32 bytes
+ * It's also good for 386/486s (which actually have 16)
* as quite a few PCI devices do not support smaller values.
*/
- pci_cache_line_size = 32 >> 2;
- if (c->x86 >= 6 && c->x86_vendor == X86_VENDOR_AMD)
- pci_cache_line_size = 64 >> 2; /* K7 & K8 */
- else if (c->x86 > 6 && c->x86_vendor == X86_VENDOR_INTEL)
- pci_cache_line_size = 128 >> 2; /* P4 */
+ if (c->x86_clflush_size > 0) {
+ pci_dfl_cache_line_size = c->x86_clflush_size >> 2;
+ printk(KERN_DEBUG "PCI: pci_cache_line_size set to %d bytes\n",
+ pci_dfl_cache_line_size << 2);
+ } else {
+ pci_dfl_cache_line_size = 32 >> 2;
+ printk(KERN_DEBUG "PCI: Unknown cacheline size. Setting to 32 bytes\n");
+ }
pcibios_resource_survey();