hw/intc/arm_gicv3_its: Implement MOVALL

Implement the ITS MOVALL command, which takes all the pending
interrupts on a source redistributor and makes the not-pending on
that source redistributor and pending on a destination redistributor.

This is a GICv3 ITS command which we forgot to implement. (It is
not used by Linux guests.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-14-peter.maydell@linaro.org

3 files changed, 125 insertions, 0 deletions

diff --git a/hw/intc/arm_gicv3_its.c b/hw/intc/arm_gicv3_its.c
index 3f2ead4..ebc0403 100644
--- a/hw/intc/arm_gicv3_its.c
+++ b/hw/intc/arm_gicv3_its.c
@@ -582,6 +582,58 @@ static ItsCmdResult process_mapd(GICv3ITSState *s, uint64_t value,
     return update_dte(s, devid, valid, size, itt_addr) ? CMD_CONTINUE : CMD_STALL;
 }
 
+static ItsCmdResult process_movall(GICv3ITSState *s, uint64_t value,
+                                   uint32_t offset)
+{
+    AddressSpace *as = &s->gicv3->dma_as;
+    MemTxResult res = MEMTX_OK;
+    uint64_t rd1, rd2;
+
+    /* No fields in dwords 0 or 1 */
+    offset += NUM_BYTES_IN_DW;
+    offset += NUM_BYTES_IN_DW;
+    value = address_space_ldq_le(as, s->cq.base_addr + offset,
+                                 MEMTXATTRS_UNSPECIFIED, &res);
+    if (res != MEMTX_OK) {
+        return CMD_STALL;
+    }
+
+    rd1 = FIELD_EX64(value, MOVALL_2, RDBASE1);
+    if (rd1 >= s->gicv3->num_cpu) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: RDBASE1 %" PRId64
+                      " out of range (must be less than %d)\n",
+                      __func__, rd1, s->gicv3->num_cpu);
+        return CMD_CONTINUE;
+    }
+
+    offset += NUM_BYTES_IN_DW;
+    value = address_space_ldq_le(as, s->cq.base_addr + offset,
+                                 MEMTXATTRS_UNSPECIFIED, &res);
+    if (res != MEMTX_OK) {
+        return CMD_STALL;
+    }
+
+    rd2 = FIELD_EX64(value, MOVALL_3, RDBASE2);
+    if (rd2 >= s->gicv3->num_cpu) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: RDBASE2 %" PRId64
+                      " out of range (must be less than %d)\n",
+                      __func__, rd2, s->gicv3->num_cpu);
+        return CMD_CONTINUE;
+    }
+
+    if (rd1 == rd2) {
+        /* Move to same target must succeed as a no-op */
+        return CMD_CONTINUE;
+    }
+
+    /* Move all pending LPIs from redistributor 1 to redistributor 2 */
+    gicv3_redist_movall_lpis(&s->gicv3->cpu[rd1], &s->gicv3->cpu[rd2]);
+
+    return CMD_CONTINUE;
+}
+
 /*
  * Current implementation blocks until all
  * commands are processed
@@ -679,6 +731,9 @@ static void process_cmdq(GICv3ITSState *s)
                 gicv3_redist_update_lpi(&s->gicv3->cpu[i]);
             }
             break;
+        case GITS_CMD_MOVALL:
+            result = process_movall(s, data, cq_offset);
+            break;
         default:
             break;
         }
diff --git a/hw/intc/arm_gicv3_redist.c b/hw/intc/arm_gicv3_redist.c
index d81d8e5..d1645ba 100644
--- a/hw/intc/arm_gicv3_redist.c
+++ b/hw/intc/arm_gicv3_redist.c
@@ -681,6 +681,60 @@ void gicv3_redist_process_lpi(GICv3CPUState *cs, int irq, int level)
     gicv3_redist_lpi_pending(cs, irq, level);
 }
 
+void gicv3_redist_movall_lpis(GICv3CPUState *src, GICv3CPUState *dest)
+{
+    /*
+     * We must move all pending LPIs from the source redistributor
+     * to the destination. That is, for every pending LPI X on
+     * src, we must set it not-pending on src and pending on dest.
+     * LPIs that are already pending on dest are not cleared.
+     *
+     * If LPIs are disabled on dest this is CONSTRAINED UNPREDICTABLE:
+     * we choose to NOP. If LPIs are disabled on source there's nothing
+     * to be transferred anyway.
+     */
+    AddressSpace *as = &src->gic->dma_as;
+    uint64_t idbits;
+    uint32_t pendt_size;
+    uint64_t src_baddr, dest_baddr;
+    int i;
+
+    if (!(src->gicr_ctlr & GICR_CTLR_ENABLE_LPIS) ||
+        !(dest->gicr_ctlr & GICR_CTLR_ENABLE_LPIS)) {
+        return;
+    }
+
+    idbits = MIN(FIELD_EX64(src->gicr_propbaser, GICR_PROPBASER, IDBITS),
+                 GICD_TYPER_IDBITS);
+    idbits = MIN(FIELD_EX64(dest->gicr_propbaser, GICR_PROPBASER, IDBITS),
+                 idbits);
+
+    pendt_size = 1ULL << (idbits + 1);
+    src_baddr = src->gicr_pendbaser & R_GICR_PENDBASER_PHYADDR_MASK;
+    dest_baddr = dest->gicr_pendbaser & R_GICR_PENDBASER_PHYADDR_MASK;
+
+    for (i = GICV3_LPI_INTID_START / 8; i < pendt_size / 8; i++) {
+        uint8_t src_pend, dest_pend;
+
+        address_space_read(as, src_baddr + i, MEMTXATTRS_UNSPECIFIED,
+                           &src_pend, sizeof(src_pend));
+        if (!src_pend) {
+            continue;
+        }
+        address_space_read(as, dest_baddr + i, MEMTXATTRS_UNSPECIFIED,
+                           &dest_pend, sizeof(dest_pend));
+        dest_pend |= src_pend;
+        src_pend = 0;
+        address_space_write(as, src_baddr + i, MEMTXATTRS_UNSPECIFIED,
+                            &src_pend, sizeof(src_pend));
+        address_space_write(as, dest_baddr + i, MEMTXATTRS_UNSPECIFIED,
+                            &dest_pend, sizeof(dest_pend));
+    }
+
+    gicv3_redist_update_lpi(src);
+    gicv3_redist_update_lpi(dest);
+}
+
 void gicv3_redist_set_irq(GICv3CPUState *cs, int irq, int level)
 {
     /* Update redistributor state for a change in an external PPI input line */
diff --git a/hw/intc/gicv3_internal.h b/hw/intc/gicv3_internal.h
index a316f6c..da45975 100644
--- a/hw/intc/gicv3_internal.h
+++ b/hw/intc/gicv3_internal.h
@@ -324,6 +324,7 @@ FIELD(GITS_TYPER, CIL, 36, 1)
 #define GITS_CMD_MAPI             0x0B
 #define GITS_CMD_INV              0x0C
 #define GITS_CMD_INVALL           0x0D
+#define GITS_CMD_MOVALL           0x0E
 #define GITS_CMD_DISCARD          0x0F
 
 /* MAPC command fields */
@@ -355,6 +356,10 @@ FIELD(MAPC, RDBASE, 16, 32)
 #define L2_TABLE_VALID_MASK       CMD_FIELD_VALID_MASK
 #define TABLE_ENTRY_VALID_MASK    (1ULL << 0)
 
+/* MOVALL command fields */
+FIELD(MOVALL_2, RDBASE1, 16, 36)
+FIELD(MOVALL_3, RDBASE2, 16, 36)
+
 /*
  * 12 bytes Interrupt translation Table Entry size
  * as per Table 5.3 in GICv3 spec
@@ -497,6 +502,17 @@ void gicv3_redist_update_lpi(GICv3CPUState *cs);
  * an incoming migration has loaded new state.
  */
 void gicv3_redist_update_lpi_only(GICv3CPUState *cs);
+/**
+ * gicv3_redist_movall_lpis:
+ * @src: source redistributor
+ * @dest: destination redistributor
+ *
+ * Scan the LPI pending table for @src, and for each pending LPI there
+ * mark it as not-pending for @src and pending for @dest, as required
+ * by the ITS MOVALL command.
+ */
+void gicv3_redist_movall_lpis(GICv3CPUState *src, GICv3CPUState *dest);
+
 void gicv3_redist_send_sgi(GICv3CPUState *cs, int grp, int irq, bool ns);
 void gicv3_init_cpuif(GICv3State *s);