diff mbox series

[v5,19/20] intel_iommu: Introduce a property to control FS1GP cap bit setting

Message ID 20241111083457.2090664-20-zhenzhong.duan@intel.com (mailing list archive)
State New
Headers show
Series intel_iommu: Enable stage-1 translation for emulated device | expand

Commit Message

Duan, Zhenzhong Nov. 11, 2024, 8:34 a.m. UTC 
This gives user flexibility to turn off FS1GP for debug purpose.

It is also useful for future nesting feature. When host IOMMU doesn't
support FS1GP but vIOMMU does, nested page table on host side works
after turning FS1GP off in vIOMMU.

This property has no effect when vIOMMU isn't in scalable modern
mode.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Clément Mathieu--Drif<clement.mathieu--drif@eviden.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
 include/hw/i386/intel_iommu.h | 1 +
 hw/i386/intel_iommu.c         | 5 ++++-
 2 files changed, 5 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
index 09ce707930..fa787d5b0d 100644
--- a/include/hw/i386/intel_iommu.h
+++ b/include/hw/i386/intel_iommu.h
@@ -307,6 +307,7 @@  struct IntelIOMMUState {
     bool dma_drain;                 /* Whether DMA r/w draining enabled */
     bool dma_translation;           /* Whether DMA translation supported */
     bool pasid;                     /* Whether to support PASID */
+    bool fs1gp;                     /* First Stage 1-GByte Page Support */
 
     /* Transient Mapping, Reserved(0) since VTD spec revision 3.2 */
     bool stale_tm;
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index a7a81aebee..043426032c 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -3834,6 +3834,7 @@  static Property vtd_properties[] = {
     DEFINE_PROP_BOOL("dma-drain", IntelIOMMUState, dma_drain, true),
     DEFINE_PROP_BOOL("dma-translation", IntelIOMMUState, dma_translation, true),
     DEFINE_PROP_BOOL("stale-tm", IntelIOMMUState, stale_tm, false),
+    DEFINE_PROP_BOOL("fs1gp", IntelIOMMUState, fs1gp, true),
     DEFINE_PROP_END_OF_LIST(),
 };
 
@@ -4562,7 +4563,9 @@  static void vtd_cap_init(IntelIOMMUState *s)
     /* TODO: read cap/ecap from host to decide which cap to be exposed. */
     if (s->scalable_modern) {
         s->ecap |= VTD_ECAP_SMTS | VTD_ECAP_FLTS;
-        s->cap |= VTD_CAP_FS1GP;
+        if (s->fs1gp) {
+            s->cap |= VTD_CAP_FS1GP;
+        }
     } else if (s->scalable_mode) {
         s->ecap |= VTD_ECAP_SMTS | VTD_ECAP_SRS | VTD_ECAP_SLTS;
     }