diff mbox series

[2/4] target/arm: Tidy sve_exception_el for CPACR_EL1 access

Message ID 20220127063428.30212-3-richard.henderson@linaro.org (mailing list archive)
State New, archived
Headers show
Series target/arm: SVE fixes versus VHE | expand

Commit Message

Richard Henderson Jan. 27, 2022, 6:34 a.m. UTC 
Extract entire fields for ZEN and FPEN, rather than testing specific bits.
This makes it easier to follow the code versus the ARM spec.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/helper.c | 36 +++++++++++++++++-------------------
 1 file changed, 17 insertions(+), 19 deletions(-)

Comments

Peter Maydell Jan. 28, 2022, 6:15 p.m. UTC | #1 
On Thu, 27 Jan 2022 at 06:34, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Extract entire fields for ZEN and FPEN, rather than testing specific bits.
> This makes it easier to follow the code versus the ARM spec.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM
Zenghui Yu Jan. 29, 2022, 6:50 a.m. UTC | #2 
On 2022/1/27 14:34, Richard Henderson wrote:
> Extract entire fields for ZEN and FPEN, rather than testing specific bits.
> This makes it easier to follow the code versus the ARM spec.
> 
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
diff mbox series

Patch

diff --git a/target/arm/helper.c b/target/arm/helper.c
index d9ee2ba5f4..cd48560786 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -6154,30 +6154,28 @@  int sve_exception_el(CPUARMState *env, int el)
     uint64_t hcr_el2 = arm_hcr_el2_eff(env);
 
     if (el <= 1 && (hcr_el2 & (HCR_E2H | HCR_TGE)) != (HCR_E2H | HCR_TGE)) {
-        bool disabled = false;
-
-        /* The CPACR.ZEN controls traps to EL1:
-         * 0, 2 : trap EL0 and EL1 accesses
-         * 1    : trap only EL0 accesses
-         * 3    : trap no accesses
-         */
-        if (!extract32(env->cp15.cpacr_el1, 16, 1)) {
-            disabled = true;
-        } else if (!extract32(env->cp15.cpacr_el1, 17, 1)) {
-            disabled = el == 0;
-        }
-        if (disabled) {
+        /* Check CPACR.ZEN.  */
+        switch (extract32(env->cp15.cpacr_el1, 16, 2)) {
+        case 1:
+            if (el != 0) {
+                break;
+            }
+            /* fall through */
+        case 0:
+        case 2:
             /* route_to_el2 */
             return hcr_el2 & HCR_TGE ? 2 : 1;
         }
 
         /* Check CPACR.FPEN.  */
-        if (!extract32(env->cp15.cpacr_el1, 20, 1)) {
-            disabled = true;
-        } else if (!extract32(env->cp15.cpacr_el1, 21, 1)) {
-            disabled = el == 0;
-        }
-        if (disabled) {
+        switch (extract32(env->cp15.cpacr_el1, 20, 2)) {
+        case 1:
+            if (el != 0) {
+                break;
+            }
+            /* fall through */
+        case 0:
+        case 2:
             return 0;
         }
     }