x86, AMD IOMMU: add early detection code

This patch adds code to detect an AMD IOMMU early during boot before the early
detection code of other IOMMUs run.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: Sebastian.Biemueller@amd.com
Cc: robert.richter@amd.com
Cc: joro@8bytes.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Joerg Roedel 2008-06-26 21:27:51 +02:00 committed by Ingo Molnar
parent fe74c9cf39
commit ae7877de9c

View File

@ -769,3 +769,23 @@ free:
goto out;
}
static int __init early_amd_iommu_detect(struct acpi_table_header *table)
{
return 0;
}
void __init amd_iommu_detect(void)
{
if (swiotlb || no_iommu || iommu_detected)
return;
if (amd_iommu_disable)
return;
if (acpi_table_parse("IVRS", early_amd_iommu_detect) == 0) {
iommu_detected = 1;
gart_iommu_aperture_disabled = 1;
gart_iommu_aperture = 0;
}
}