x86, AMD IOMMU: don't try to init IOMMU if early detect code did not detect one

This patch adds a check if the early detect code has found AMD IOMMU hardware
descriptions and does not try to initialize hardware if the check failed.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: robert.richter@amd.com
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Joerg Roedel 2008-07-03 19:35:10 +02:00 committed by Ingo Molnar
parent 8b14518fad
commit c1cbebeec4

View file

@ -101,6 +101,8 @@ struct ivmd_header {
u64 range_length;
} __attribute__((packed));
static int __initdata amd_iommu_detected;
u16 amd_iommu_last_bdf;
struct list_head amd_iommu_unity_map;
unsigned amd_iommu_aperture_order = 26;
@ -689,6 +691,9 @@ int __init amd_iommu_init(void)
return 0;
}
if (!amd_iommu_detected)
return -ENODEV;
/*
* First parse ACPI tables to find the largest Bus/Dev/Func
* we need to handle. Upon this information the shared data
@ -831,6 +836,7 @@ void __init amd_iommu_detect(void)
if (acpi_table_parse("IVRS", early_amd_iommu_detect) == 0) {
iommu_detected = 1;
amd_iommu_detected = 1;
#ifdef CONFIG_GART_IOMMU
gart_iommu_aperture_disabled = 1;
gart_iommu_aperture = 0;