[PATCH 37/50] ACPI, x86: Use SRAT table rev to use 8bit or 32bit PXMfields (x86/x86-64)

From: Len Brown
Date: Tue Jan 17 2012 - 08:25:02 EST


From: Kurt Garloff <kurt@xxxxxxxxxx>

In SRAT v1, we had 8bit proximity domain (PXM) fields; SRAT v2 provides
32bits for these. The new fields were reserved before.
According to the ACPI spec, the OS must disregrard reserved fields.

x86/x86-64 was rather inconsistent prior to this patch; it used 8 bits
for the pxm field in cpu_affinity, but 32 bits in mem_affinity.
This patch makes it consistent: Either use 8 bits consistently (SRAT
rev 1 or lower) or 32 bits (SRAT rev 2 or higher).

cc: x86@xxxxxxxxxx
Signed-off-by: Kurt Garloff <kurt@xxxxxxxxxx>
Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
---
arch/x86/mm/srat.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/arch/x86/mm/srat.c b/arch/x86/mm/srat.c
index 81dbfde..7efd0c6 100644
--- a/arch/x86/mm/srat.c
+++ b/arch/x86/mm/srat.c
@@ -104,6 +104,8 @@ acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa)
if ((pa->flags & ACPI_SRAT_CPU_ENABLED) == 0)
return;
pxm = pa->proximity_domain_lo;
+ if (acpi_srat_revision >= 2)
+ pxm |= *((unsigned int*)pa->proximity_domain_hi) << 8;
node = setup_node(pxm);
if (node < 0) {
printk(KERN_ERR "SRAT: Too many proximity domains %x\n", pxm);
@@ -155,6 +157,8 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
start = ma->base_address;
end = start + ma->length;
pxm = ma->proximity_domain;
+ if (acpi_srat_revision <= 1)
+ pxm &= 0xff;
node = setup_node(pxm);
if (node < 0) {
printk(KERN_ERR "SRAT: Too many proximity domains.\n");
--
1.7.9.rc1

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