intel_iommu: define interrupt remap table addr register

Defined Interrupt Remap Table Address register to store IR table
pointer. Also, do proper handling on global command register writes to
store table pointer and its size.

One more debug flag "DEBUG_IR" is added for interrupt remapping.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 9c7a084..bf74533 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -33,7 +33,7 @@
 #ifdef DEBUG_INTEL_IOMMU
 enum {
     DEBUG_GENERAL, DEBUG_CSR, DEBUG_INV, DEBUG_MMU, DEBUG_FLOG,
-    DEBUG_CACHE,
+    DEBUG_CACHE, DEBUG_IR,
 };
 #define VTD_DBGBIT(x)   (1 << DEBUG_##x)
 static int vtd_dbgflags = VTD_DBGBIT(GENERAL) | VTD_DBGBIT(CSR);
@@ -903,6 +903,19 @@
                 (s->root_extended ? "(extended)" : ""));
 }
 
+static void vtd_interrupt_remap_table_setup(IntelIOMMUState *s)
+{
+    uint64_t value = 0;
+    value = vtd_get_quad_raw(s, DMAR_IRTA_REG);
+    s->intr_size = 1UL << ((value & VTD_IRTA_SIZE_MASK) + 1);
+    s->intr_root = value & VTD_IRTA_ADDR_MASK;
+
+    /* TODO: invalidate interrupt entry cache */
+
+    VTD_DPRINTF(CSR, "int remap table addr 0x%"PRIx64 " size %"PRIu32,
+                s->intr_root, s->intr_size);
+}
+
 static void vtd_context_global_invalidate(IntelIOMMUState *s)
 {
     s->context_cache_gen++;
@@ -1141,6 +1154,16 @@
     vtd_set_clear_mask_long(s, DMAR_GSTS_REG, 0, VTD_GSTS_RTPS);
 }
 
+/* Set Interrupt Remap Table Pointer */
+static void vtd_handle_gcmd_sirtp(IntelIOMMUState *s)
+{
+    VTD_DPRINTF(CSR, "set Interrupt Remap Table Pointer");
+
+    vtd_interrupt_remap_table_setup(s);
+    /* Ok - report back to driver */
+    vtd_set_clear_mask_long(s, DMAR_GSTS_REG, 0, VTD_GSTS_IRTPS);
+}
+
 /* Handle Translation Enable/Disable */
 static void vtd_handle_gcmd_te(IntelIOMMUState *s, bool en)
 {
@@ -1180,6 +1203,10 @@
         /* Queued Invalidation Enable */
         vtd_handle_gcmd_qie(s, val & VTD_GCMD_QIE);
     }
+    if (val & VTD_GCMD_SIRTP) {
+        /* Set/update the interrupt remapping root-table pointer */
+        vtd_handle_gcmd_sirtp(s);
+    }
 }
 
 /* Handle write to Context Command Register */
@@ -1841,6 +1868,23 @@
         vtd_update_fsts_ppf(s);
         break;
 
+    case DMAR_IRTA_REG:
+        VTD_DPRINTF(IR, "DMAR_IRTA_REG write addr 0x%"PRIx64
+                    ", size %d, val 0x%"PRIx64, addr, size, val);
+        if (size == 4) {
+            vtd_set_long(s, addr, val);
+        } else {
+            vtd_set_quad(s, addr, val);
+        }
+        break;
+
+    case DMAR_IRTA_REG_HI:
+        VTD_DPRINTF(IR, "DMAR_IRTA_REG_HI write addr 0x%"PRIx64
+                    ", size %d, val 0x%"PRIx64, addr, size, val);
+        assert(size == 4);
+        vtd_set_long(s, addr, val);
+        break;
+
     default:
         VTD_DPRINTF(GENERAL, "error: unhandled reg write addr 0x%"PRIx64
                     ", size %d, val 0x%"PRIx64, addr, size, val);
@@ -2032,6 +2076,12 @@
     /* Fault Recording Registers, 128-bit */
     vtd_define_quad(s, DMAR_FRCD_REG_0_0, 0, 0, 0);
     vtd_define_quad(s, DMAR_FRCD_REG_0_2, 0, 0, 0x8000000000000000ULL);
+
+    /*
+     * Interrupt remapping registers, not support extended interrupt
+     * mode for now.
+     */
+    vtd_define_quad(s, DMAR_IRTA_REG, 0, 0xfffffffffffff00fULL, 0);
 }
 
 /* Should not reset address_spaces when reset because devices will still use
diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index 5b98a11..309833f 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -172,6 +172,10 @@
 #define VTD_RTADDR_RTT              (1ULL << 11)
 #define VTD_RTADDR_ADDR_MASK        (VTD_HAW_MASK ^ 0xfffULL)
 
+/* IRTA_REG */
+#define VTD_IRTA_ADDR_MASK          (VTD_HAW_MASK ^ 0xfffULL)
+#define VTD_IRTA_SIZE_MASK          (0xfULL)
+
 /* ECAP_REG */
 /* (offset >> 4) << 8 */
 #define VTD_ECAP_IRO                (DMAR_IOTLB_REG_OFFSET << 4)
diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
index 741242e..ce515c4 100644
--- a/include/hw/i386/intel_iommu.h
+++ b/include/hw/i386/intel_iommu.h
@@ -125,6 +125,11 @@
     MemoryRegionIOMMUOps iommu_ops;
     GHashTable *vtd_as_by_busptr;   /* VTDBus objects indexed by PCIBus* reference */
     VTDBus *vtd_as_by_bus_num[VTD_PCI_BUS_MAX]; /* VTDBus objects indexed by bus number */
+
+    /* interrupt remapping */
+    bool intr_enabled;              /* Whether guest enabled IR */
+    dma_addr_t intr_root;           /* Interrupt remapping table pointer */
+    uint32_t intr_size;             /* Number of IR table entries */
 };
 
 /* Find the VTD Address space associated with the given bus pointer,