target/arm: Implement M-profile VPR register

If MVE is implemented for an M-profile CPU then it has a VPR
register, which tracks predication information.

Implement the read and write handling of this register, and
the migration of its state.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210520152840.24453-7-peter.maydell@linaro.org

1 files changed, 19 insertions, 0 deletions

diff --git a/target/arm/machine.c b/target/arm/machine.c
index 6ad1d306b1..62a71a3b64 100644
--- a/target/arm/machine.c
+++ b/target/arm/machine.c
@@ -318,6 +318,24 @@ static const VMStateDescription vmstate_m_fp = {
     }
 };
 
+static bool mve_needed(void *opaque)
+{
+    ARMCPU *cpu = opaque;
+
+    return cpu_isar_feature(aa32_mve, cpu);
+}
+
+static const VMStateDescription vmstate_m_mve = {
+    .name = "cpu/m/mve",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = mve_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(env.v7m.vpr, ARMCPU),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
 static const VMStateDescription vmstate_m = {
     .name = "cpu/m",
     .version_id = 4,
@@ -344,6 +362,7 @@ static const VMStateDescription vmstate_m = {
         &vmstate_m_other_sp,
         &vmstate_m_v8m,
         &vmstate_m_fp,
+        &vmstate_m_mve,
         NULL
     }
 };