target/arm: Only set ZEN in reset if SVE present

There's no reason to set CPACR_EL1.ZEN if SVE disabled.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220708151540.18136-44-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 9c58be8..9b54443 100644 (file)
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -204,11 +204,10 @@ static void arm_cpu_reset(DeviceState *dev)
         /* and to the FP/Neon instructions */
         env->cp15.cpacr_el1 = FIELD_DP64(env->cp15.cpacr_el1,
                                          CPACR_EL1, FPEN, 3);
-        /* and to the SVE instructions */
-        env->cp15.cpacr_el1 = FIELD_DP64(env->cp15.cpacr_el1,
-                                         CPACR_EL1, ZEN, 3);
-        /* with reasonable vector length */
+        /* and to the SVE instructions, with default vector length */
         if (cpu_isar_feature(aa64_sve, cpu)) {
+            env->cp15.cpacr_el1 = FIELD_DP64(env->cp15.cpacr_el1,
+                                             CPACR_EL1, ZEN, 3);
             env->vfp.zcr_el[1] = cpu->sve_default_vq - 1;
         }
         /*