Merge pull request #486 from ved-rivos/0217_1

G field is not set for MSI trans
riscv-non-isa · Feb 17, 2025 · f92572d · f92572d
2 parents 5e7bf12 + 3b04005
commit f92572d
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Showing 2 changed files with 9 additions and 5 deletions.
diff --git a/iommu_ref_model/libiommu/src/iommu_msi_trans.c b/iommu_ref_model/libiommu/src/iommu_msi_trans.c
@@ -116,10 +116,10 @@ msi_address_translation(
         *pa = ((msipte.translate_rw.PPN * PAGESIZE) | (A & 0xFFF));
         g_pte->raw = 0;
         g_pte->PPN = gpa / PAGESIZE;
-        g_pte->D = g_pte->A = g_pte->G = g_pte->U = 1;
+        g_pte->D = g_pte->A = g_pte->U = 1;
         g_pte->X = 0;
         g_pte->W = g_pte->R = g_pte->V = 1;
-        g_pte->N = 0;
+        g_pte->N = g_pte->G = 0;
         g_pte->PBMT = PMA;
         *page_sz = PAGESIZE;
         *is_mrif = 0;
@@ -156,10 +156,10 @@ msi_address_translation(
     *is_mrif = 1;
     g_pte->raw = 0;
     g_pte->PPN = gpa / PAGESIZE;
-    g_pte->D = g_pte->A = g_pte->G = g_pte->U = 1;
+    g_pte->D = g_pte->A = g_pte->U = 1;
     g_pte->X = 0;
     g_pte->W = g_pte->R = g_pte->V = 1;
-    g_pte->N = 0;
+    g_pte->N = g_pte->G = 0;
     g_pte->PBMT = PMA;
     *page_sz = PAGESIZE;
 

diff --git a/iommu_ref_model/libiommu/src/iommu_translate.c b/iommu_ref_model/libiommu/src/iommu_translate.c
@@ -408,6 +408,10 @@ iommu_translate_iova(
         // receive the Priv bit Clear and thus don’t need to cache it.
         // An ATC that receives a translation with R=W=0b for one privilege level may not
         // assume anything about what it might receive for the other privilege level.
+        // * Global field is set to the value determined from the first-stage page tables
+        //   if translation could be successfully completed and the request had a PASID
+        //   present. In all other cases, including MSI address translations, this field
+        //   is set to 0.
         // * N field of the ATS translation completion is always set to 0. The device may
         //   use other means to determine if the No-snoop flag should be set in the
         //   translated requests.
@@ -463,7 +467,7 @@ iommu_translate_iova(
                                 ((vs_pte.PBMT != PMA) || (is_msi == 1) || (DC.tc.T2GPA == 1))) ? 1 : 0;
         rsp_msg->trsp.N      = 0;
         rsp_msg->trsp.AMA    = 0;
-        rsp_msg->trsp.Global = req->pid_valid ? vs_pte.G : 0;
+        rsp_msg->trsp.Global = req->pid_valid && (is_msi == 0) ? vs_pte.G : 0;
         rsp_msg->trsp.U      = (is_msi & is_mrif);
         rsp_msg->trsp.R      = (vs_pte.R & g_pte.R);
         rsp_msg->trsp.W      = (vs_pte.W & g_pte.W & vs_pte.D & g_pte.D);