target/arm: Enable FP16 in '-cpu max'

Set the MVFR1 ID register FPHP and SIMDHP fields to indicate
that our "-cpu max" has v8.2-FP16.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200828183354.27913-46-peter.maydell@linaro.org

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 6b382fcd60e89e94f295e595c862c627652fbf7e..c179e0752da81e2d5ad1ee31dbf662061656d126 100644 (file)
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -2143,7 +2143,8 @@ static void arm_max_initfn(Object *obj)
             cpu->isar.id_isar6 = t;
 
             t = cpu->isar.mvfr1;
-            t = FIELD_DP32(t, MVFR1, FPHP, 2);     /* v8.0 FP support */
+            t = FIELD_DP32(t, MVFR1, FPHP, 3);     /* v8.2-FP16 */
+            t = FIELD_DP32(t, MVFR1, SIMDHP, 2);   /* v8.2-FP16 */
             cpu->isar.mvfr1 = t;
 
             t = cpu->isar.mvfr2;

diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index dd696183dfb5b3010964e345ee99bfb4726f2216..3c2b3d959937968803f04bbdd4192119141fe4c3 100644 (file)
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -704,12 +704,10 @@ static void aarch64_max_initfn(Object *obj)
         u = FIELD_DP32(u, ID_DFR0, PERFMON, 5); /* v8.4-PMU */
         cpu->isar.id_dfr0 = u;
 
-        /*
-         * FIXME: We do not yet support ARMv8.2-fp16 for AArch32 yet,
-         * so do not set MVFR1.FPHP.  Strictly speaking this is not legal,
-         * but it is also not legal to enable SVE without support for FP16,
-         * and enabling SVE in system mode is more useful in the short term.
-         */
+        u = cpu->isar.mvfr1;
+        u = FIELD_DP32(u, MVFR1, FPHP, 3);      /* v8.2-FP16 */
+        u = FIELD_DP32(u, MVFR1, SIMDHP, 2);    /* v8.2-FP16 */
+        cpu->isar.mvfr1 = u;
 
 #ifdef CONFIG_USER_ONLY
         /* For usermode -cpu max we can use a larger and more efficient DCZ