xen/19154-snoop-control.patch

69 lines
2.4 KiB
Diff

# HG changeset patch
# User Keir Fraser <keir.fraser@citrix.com>
# Date 1233748806 0
# Node ID 6058887e55d7096f8b32c1f0576c601b080dc879
# Parent 7e15ccb7bbd88e550ada6a6b86196cc4e5d880b6
vtd: Add a boot parameter option for snoop control capability for VT-d.
The default is to use snoop control.
Signed-off-by: Xin, Xiaohui <xiaohui.xin@intel.com>
Index: xen-3.3.1-testing/xen/drivers/passthrough/iommu.c
===================================================================
--- xen-3.3.1-testing.orig/xen/drivers/passthrough/iommu.c
+++ xen-3.3.1-testing/xen/drivers/passthrough/iommu.c
@@ -34,6 +34,8 @@ int amd_iov_detect(void);
* no-pv Disable IOMMU for PV domains (default)
* force|required Don't boot unless IOMMU is enabled
* passthrough Bypass VT-d translation for Dom0
+ * snoop Utilize the snoop control for IOMMU (default)
+ * no-snoop Dont utilize the snoop control for IOMMU
*/
custom_param("iommu", parse_iommu_param);
int iommu_enabled = 0;
@@ -46,6 +48,7 @@ static void __init parse_iommu_param(cha
{
char *ss;
iommu_enabled = 1;
+ iommu_snoop = 1;
do {
ss = strchr(s, ',');
@@ -63,6 +66,10 @@ static void __init parse_iommu_param(cha
force_iommu = 1;
else if ( !strcmp(s, "passthrough") )
iommu_passthrough = 1;
+ else if ( !strcmp(s, "snoop") )
+ iommu_snoop = 1;
+ else if ( !strcmp(s, "no-snoop") )
+ iommu_snoop = 0;
s = ss + 1;
} while ( ss );
Index: xen-3.3.1-testing/xen/drivers/passthrough/vtd/dmar.c
===================================================================
--- xen-3.3.1-testing.orig/xen/drivers/passthrough/vtd/dmar.c
+++ xen-3.3.1-testing/xen/drivers/passthrough/vtd/dmar.c
@@ -530,13 +530,15 @@ int acpi_dmar_init(void)
/* Giving that all devices within guest use same io page table,
* enable snoop control only if all VT-d engines support it.
*/
- iommu_snoop = 1;
- for_each_drhd_unit ( drhd )
+ if ( iommu_snoop )
{
- iommu = drhd->iommu;
- if ( !ecap_snp_ctl(iommu->ecap) ) {
- iommu_snoop = 0;
- break;
+ for_each_drhd_unit ( drhd )
+ {
+ iommu = drhd->iommu;
+ if ( !ecap_snp_ctl(iommu->ecap) ) {
+ iommu_snoop = 0;
+ break;
+ }
}
}