[PATCH v2 15/17] intel_iommu: Modify x-scalable-mode to be string option to expose scalable modern mode

[Zhenzhong Duan]

From: Yi Liu <yi.l.liu@intel.com>

Intel VT-d 3.0 introduces scalable mode, and it has a bunch of capabilities
related to scalable mode translation, thus there are multiple combinations.
While this vIOMMU implementation wants to simplify it for user by providing
typical combinations. User could config it by "x-scalable-mode" option. The
usage is as below:

"-device intel-iommu,x-scalable-mode=["legacy"|"modern"|"off"]"

 - "legacy": gives support for stage-2 page table
 - "modern": gives support for stage-1 page table
 - "off": no scalable mode support
 - any other string, will throw error

If x-scalable-mode is not configured, it is equivalent to x-scalable-mode=off.

With scalable modern mode exposed to user, also accurate the pasid entry
check in vtd_pe_type_check().

Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/i386/intel_iommu_internal.h |  2 ++
 include/hw/i386/intel_iommu.h  |  1 +
 hw/i386/intel_iommu.c          | 46 ++++++++++++++++++++++++++--------
 3 files changed, 39 insertions(+), 10 deletions(-)

diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index 52bdbf3bc5..af99deb4cd 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -195,6 +195,7 @@
 #define VTD_ECAP_PASID              (1ULL << 40)
 #define VTD_ECAP_SMTS               (1ULL << 43)
 #define VTD_ECAP_SLTS               (1ULL << 46)
+#define VTD_ECAP_FLTS               (1ULL << 47)
 
 /* CAP_REG */
 /* (offset >> 4) << 24 */
@@ -211,6 +212,7 @@
 #define VTD_CAP_SLLPS               ((1ULL << 34) | (1ULL << 35))
 #define VTD_CAP_DRAIN_WRITE         (1ULL << 54)
 #define VTD_CAP_DRAIN_READ          (1ULL << 55)
+#define VTD_CAP_FS1GP               (1ULL << 56)
 #define VTD_CAP_DRAIN               (VTD_CAP_DRAIN_READ | VTD_CAP_DRAIN_WRITE)
 #define VTD_CAP_CM                  (1ULL << 7)
 #define VTD_PASID_ID_SHIFT          20
diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
index 48134bda11..650641544c 100644
--- a/include/hw/i386/intel_iommu.h
+++ b/include/hw/i386/intel_iommu.h
@@ -263,6 +263,7 @@ struct IntelIOMMUState {
 
     bool caching_mode;              /* RO - is cap CM enabled? */
     bool scalable_mode;             /* RO - is Scalable Mode supported? */
+    char *scalable_mode_str;        /* RO - admin's Scalable Mode config */
     bool scalable_modern;           /* RO - is modern SM supported? */
     bool snoop_control;             /* RO - is SNP filed supported? */
 
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 5469ab4f9b..9e973bd710 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -803,16 +803,18 @@ static inline bool 
vtd_is_fl_level_supported(IntelIOMMUState *s, uint32_t level)
 }
 
 /* Return true if check passed, otherwise false */
-static inline bool vtd_pe_type_check(X86IOMMUState *x86_iommu,
-                                     VTDPASIDEntry *pe)
+static inline bool vtd_pe_type_check(IntelIOMMUState *s, VTDPASIDEntry *pe)
 {
     switch (VTD_PE_GET_TYPE(pe)) {
-    case VTD_SM_PASID_ENTRY_SLT:
-        return true;
-    case VTD_SM_PASID_ENTRY_PT:
-        return x86_iommu->pt_supported;
     case VTD_SM_PASID_ENTRY_FLT:
+        return !!(s->ecap & VTD_ECAP_FLTS);
+    case VTD_SM_PASID_ENTRY_SLT:
+        return !!(s->ecap & VTD_ECAP_SLTS) || !(s->ecap & VTD_ECAP_SMTS);
     case VTD_SM_PASID_ENTRY_NESTED:
+        /* Not support NESTED page table type yet */
+        return false;
+    case VTD_SM_PASID_ENTRY_PT:
+        return !!(s->ecap & VTD_ECAP_PT);
     default:
         /* Unknown type */
         return false;
@@ -861,7 +863,6 @@ static int vtd_get_pe_in_pasid_leaf_table(IntelIOMMUState 
*s,
     uint8_t pgtt;
     uint32_t index;
     dma_addr_t entry_size;
-    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(s);
 
     index = VTD_PASID_TABLE_INDEX(pasid);
     entry_size = VTD_PASID_ENTRY_SIZE;
@@ -875,7 +876,7 @@ static int vtd_get_pe_in_pasid_leaf_table(IntelIOMMUState 
*s,
     }
 
     /* Do translation type check */
-    if (!vtd_pe_type_check(x86_iommu, pe)) {
+    if (!vtd_pe_type_check(s, pe)) {
         return -VTD_FR_PASID_TABLE_ENTRY_INV;
     }
 
@@ -3772,7 +3773,7 @@ static Property vtd_properties[] = {
     DEFINE_PROP_UINT8("aw-bits", IntelIOMMUState, aw_bits,
                       VTD_HOST_AW_AUTO),
     DEFINE_PROP_BOOL("caching-mode", IntelIOMMUState, caching_mode, FALSE),
-    DEFINE_PROP_BOOL("x-scalable-mode", IntelIOMMUState, scalable_mode, FALSE),
+    DEFINE_PROP_STRING("x-scalable-mode", IntelIOMMUState, scalable_mode_str),
     DEFINE_PROP_BOOL("snoop-control", IntelIOMMUState, snoop_control, false),
     DEFINE_PROP_BOOL("x-pasid-mode", IntelIOMMUState, pasid, false),
     DEFINE_PROP_BOOL("dma-drain", IntelIOMMUState, dma_drain, true),
@@ -4503,7 +4504,10 @@ static void vtd_cap_init(IntelIOMMUState *s)
     }
 
     /* TODO: read cap/ecap from host to decide which cap to be exposed. */
-    if (s->scalable_mode) {
+    if (s->scalable_modern) {
+        s->ecap |= VTD_ECAP_SMTS | VTD_ECAP_FLTS;
+        s->cap |= VTD_CAP_FS1GP;
+    } else if (s->scalable_mode) {
         s->ecap |= VTD_ECAP_SMTS | VTD_ECAP_SRS | VTD_ECAP_SLTS;
     }
 
@@ -4685,6 +4689,28 @@ static bool vtd_decide_config(IntelIOMMUState *s, Error 
**errp)
         }
     }
 
+    if (s->scalable_mode_str &&
+        (strcmp(s->scalable_mode_str, "off") &&
+         strcmp(s->scalable_mode_str, "modern") &&
+         strcmp(s->scalable_mode_str, "legacy"))) {
+        error_setg(errp, "Invalid x-scalable-mode config,"
+                         "Please use \"modern\", \"legacy\" or \"off\"");
+        return false;
+    }
+
+    if (s->scalable_mode_str &&
+        !strcmp(s->scalable_mode_str, "legacy")) {
+        s->scalable_mode = true;
+        s->scalable_modern = false;
+    } else if (s->scalable_mode_str &&
+        !strcmp(s->scalable_mode_str, "modern")) {
+        s->scalable_mode = true;
+        s->scalable_modern = true;
+    } else {
+        s->scalable_mode = false;
+        s->scalable_modern = false;
+    }
+
     if (s->aw_bits == VTD_HOST_AW_AUTO) {
         if (s->scalable_modern) {
             s->aw_bits = VTD_HOST_AW_48BIT;
-- 
2.34.1