hw/intc/arm_gicv3_its: Implement VMAPP

Implement the GICv4 VMAPP command, which writes an entry to the vPE
table.

For GICv4.1 this command has extra fields in the command packet
and additional behaviour. We define the 4.1-only fields with the
FIELD macro, but only implement the GICv4.0 version of the command.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-10-peter.maydell@linaro.org

1 files changed, 88 insertions, 0 deletions

diff --git a/hw/intc/arm_gicv3_its.c b/hw/intc/arm_gicv3_its.c
index 8aed57e704..880bc6f647 100644
--- a/hw/intc/arm_gicv3_its.c
+++ b/hw/intc/arm_gicv3_its.c
@@ -61,6 +61,12 @@ typedef struct ITEntry {
     uint32_t vpeid;
 } ITEntry;
 
+typedef struct VTEntry {
+    bool valid;
+    unsigned vptsize;
+    uint32_t rdbase;
+    uint64_t vptaddr;
+} VTEntry;
 
 /*
  * The ITS spec permits a range of CONSTRAINED UNPREDICTABLE options
@@ -843,6 +849,85 @@ static ItsCmdResult process_movi(GICv3ITSState *s, const uint64_t *cmdpkt)
 }
 
 /*
+ * Update the vPE Table entry at index @vpeid with the entry @vte.
+ * Returns true on success, false if there was a memory access error.
+ */
+static bool update_vte(GICv3ITSState *s, uint32_t vpeid, const VTEntry *vte)
+{
+    AddressSpace *as = &s->gicv3->dma_as;
+    uint64_t entry_addr;
+    uint64_t vteval = 0;
+    MemTxResult res = MEMTX_OK;
+
+    trace_gicv3_its_vte_write(vpeid, vte->valid, vte->vptsize, vte->vptaddr,
+                              vte->rdbase);
+
+    if (vte->valid) {
+        vteval = FIELD_DP64(vteval, VTE, VALID, 1);
+        vteval = FIELD_DP64(vteval, VTE, VPTSIZE, vte->vptsize);
+        vteval = FIELD_DP64(vteval, VTE, VPTADDR, vte->vptaddr);
+        vteval = FIELD_DP64(vteval, VTE, RDBASE, vte->rdbase);
+    }
+
+    entry_addr = table_entry_addr(s, &s->vpet, vpeid, &res);
+    if (res != MEMTX_OK) {
+        return false;
+    }
+    if (entry_addr == -1) {
+        /* No L2 table for this index: discard write and continue */
+        return true;
+    }
+    address_space_stq_le(as, entry_addr, vteval, MEMTXATTRS_UNSPECIFIED, &res);
+    return res == MEMTX_OK;
+}
+
+static ItsCmdResult process_vmapp(GICv3ITSState *s, const uint64_t *cmdpkt)
+{
+    VTEntry vte;
+    uint32_t vpeid;
+
+    if (!its_feature_virtual(s)) {
+        return CMD_CONTINUE;
+    }
+
+    vpeid = FIELD_EX64(cmdpkt[1], VMAPP_1, VPEID);
+    vte.rdbase = FIELD_EX64(cmdpkt[2], VMAPP_2, RDBASE);
+    vte.valid = FIELD_EX64(cmdpkt[2], VMAPP_2, V);
+    vte.vptsize = FIELD_EX64(cmdpkt[3], VMAPP_3, VPTSIZE);
+    vte.vptaddr = FIELD_EX64(cmdpkt[3], VMAPP_3, VPTADDR);
+
+    trace_gicv3_its_cmd_vmapp(vpeid, vte.rdbase, vte.valid,
+                              vte.vptaddr, vte.vptsize);
+
+    /*
+     * For GICv4.0 the VPT_size field is only 5 bits, whereas we
+     * define our field macros to include the full GICv4.1 8 bits.
+     * The range check on VPT_size will catch the cases where
+     * the guest set the RES0-in-GICv4.0 bits [7:6].
+     */
+    if (vte.vptsize > FIELD_EX64(s->typer, GITS_TYPER, IDBITS)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: invalid VPT_size 0x%x\n", __func__, vte.vptsize);
+        return CMD_CONTINUE;
+    }
+
+    if (vte.valid && vte.rdbase >= s->gicv3->num_cpu) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: invalid rdbase 0x%x\n", __func__, vte.rdbase);
+        return CMD_CONTINUE;
+    }
+
+    if (vpeid >= s->vpet.num_entries) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: VPEID 0x%x out of range (must be less than 0x%x)\n",
+                      __func__, vpeid, s->vpet.num_entries);
+        return CMD_CONTINUE;
+    }
+
+    return update_vte(s, vpeid, &vte) ? CMD_CONTINUE : CMD_STALL;
+}
+
+/*
  * Current implementation blocks until all
  * commands are processed
  */
@@ -963,6 +1048,9 @@ static void process_cmdq(GICv3ITSState *s)
         case GITS_CMD_VMAPI:
             result = process_vmapti(s, cmdpkt, true);
             break;
+        case GITS_CMD_VMAPP:
+            result = process_vmapp(s, cmdpkt);
+            break;
         default:
             trace_gicv3_its_cmd_unknown(cmd);
             break;