[RFC v3.1 22/22] intel_iommu: modify x-scalable-mode to be string option

[Liu Yi L <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 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 SL page table
 - "modern": gives support for FL page table, pasid, virtual command
 - "off": no scalable mode support
 -  if not configured, means no scalable mode support, if not proper
    configured, will throw error

Note: this patch is supposed to be merged when  the whole vSVA patch series
were merged.

Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Yi Sun <yi.y.sun@linux.intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
---
 hw/i386/intel_iommu.c          | 29 +++++++++++++++++++++++++++--
 hw/i386/intel_iommu_internal.h |  4 ++++
 include/hw/i386/intel_iommu.h  |  2 ++
 3 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index f5faa75..51b00ee 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -4205,7 +4205,7 @@ static Property vtd_properties[] = {
     DEFINE_PROP_UINT8("aw-bits", IntelIOMMUState, aw_bits,
                       VTD_HOST_ADDRESS_WIDTH),
     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("dma-drain", IntelIOMMUState, dma_drain, true),
     DEFINE_PROP_END_OF_LIST(),
 };
@@ -4768,8 +4768,12 @@ static void vtd_init(IntelIOMMUState *s)
     }
 
     /* TODO: read cap/ecap from host to decide which cap to be exposed. */
-    if (s->scalable_mode) {
+    if (s->scalable_mode && !s->scalable_modern) {
         s->ecap |= VTD_ECAP_SMTS | VTD_ECAP_SRS | VTD_ECAP_SLTS;
+    } else if (s->scalable_mode && s->scalable_modern) {
+        s->ecap |= VTD_ECAP_SMTS | VTD_ECAP_SRS | VTD_ECAP_PASID
+                   | VTD_ECAP_FLTS | VTD_ECAP_PSS | VTD_ECAP_VCS;
+        s->vccap |= VTD_VCCAP_PAS;
     }
 
     vtd_reset_caches(s);
@@ -4895,6 +4899,27 @@ static bool vtd_decide_config(IntelIOMMUState *s, Error **errp)
         return false;
     }
 
+    if (s->scalable_mode_str &&
+        (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;
+    }
+
     return true;
 }
 
diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index dfb54fc..f7de046 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -196,8 +196,12 @@
 #define VTD_ECAP_PT                 (1ULL << 6)
 #define VTD_ECAP_MHMV               (15ULL << 20)
 #define VTD_ECAP_SRS                (1ULL << 31)
+#define VTD_ECAP_PSS                (19ULL << 35)
+#define VTD_ECAP_PASID              (1ULL << 40)
 #define VTD_ECAP_SMTS               (1ULL << 43)
+#define VTD_ECAP_VCS                (1ULL << 44)
 #define VTD_ECAP_SLTS               (1ULL << 46)
+#define VTD_ECAP_FLTS               (1ULL << 47)
 
 /* CAP_REG */
 /* (offset >> 4) << 24 */
diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
index ff41af0..94ead20 100644
--- a/include/hw/i386/intel_iommu.h
+++ b/include/hw/i386/intel_iommu.h
@@ -259,6 +259,8 @@ 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? */
 
     dma_addr_t root;                /* Current root table pointer */
     bool root_scalable;             /* Type of root table (scalable or not) */
-- 
2.7.4