diff mbox series

[05/22] target/arm: SCR_EL3.NS may be RES1

Message ID 20230124000027.3565716-6-richard.henderson@linaro.org
State New
Headers show
Series target/arm: Implement FEAT_RME | expand

Commit Message

Richard Henderson Jan. 24, 2023, midnight UTC
With RME, SEL2 must also be present to support secure state.
The NS bit is RES1 if SEL2 is not present.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/helper.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Peter Maydell Feb. 7, 2023, 2:39 p.m. UTC | #1
On Tue, 24 Jan 2023 at 00:05, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> With RME, SEL2 must also be present to support secure state.
> The NS bit is RES1 if SEL2 is not present.

I couldn't find the bit of the spec that says this --
could you give me a page reference?

thanks
-- PMM
Richard Henderson Feb. 7, 2023, 7:43 p.m. UTC | #2
On 2/7/23 04:39, Peter Maydell wrote:
> On Tue, 24 Jan 2023 at 00:05, Richard Henderson
> <richard.henderson@linaro.org> wrote:
>>
>> With RME, SEL2 must also be present to support secure state.
>> The NS bit is RES1 if SEL2 is not present.
> 
> I couldn't find the bit of the spec that says this --
> could you give me a page reference?

DDI0615D.a RME Supplement, R_GSWWH.
and the bit about secure state is I_DJJQJ.


r~
diff mbox series

Patch

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 293f8eda8c..783b675bd1 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -1853,6 +1853,9 @@  static void scr_write(CPUARMState *env, const ARMCPRegInfo *ri, uint64_t value)
         }
         if (cpu_isar_feature(aa64_sel2, cpu)) {
             valid_mask |= SCR_EEL2;
+        } else if (cpu_isar_feature(aa64_rme, cpu)) {
+            /* With RME and without SEL2, NS is RES1. */
+            value |= SCR_NS;
         }
         if (cpu_isar_feature(aa64_mte, cpu)) {
             valid_mask |= SCR_ATA;