[PATCH v2 10/11] target/arm: Implement FEAT_HPDS2 as a no-op

Richard Henderson posted 11 patches 2 years, 6 months ago
Maintainers: Peter Maydell <peter.maydell@linaro.org>
There is a newer version of this series
[PATCH v2 10/11] target/arm: Implement FEAT_HPDS2 as a no-op
Posted by Richard Henderson 2 years, 6 months ago
This feature allows the operating system to set TCR_ELx.HWU*
to allow the implementation to use the PBHA bits from the
block and page descriptors for for IMPLEMENTATION DEFINED
purposes.  Since QEMU has no need to use these bits, we may
simply ignore them.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 docs/system/arm/emulation.rst | 1 +
 target/arm/tcg/cpu32.c        | 2 +-
 target/arm/tcg/cpu64.c        | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst
index bdafc68819..2012bbf7c7 100644
--- a/docs/system/arm/emulation.rst
+++ b/docs/system/arm/emulation.rst
@@ -40,6 +40,7 @@ the following architecture extensions:
 - FEAT_HAFDBS (Hardware management of the access flag and dirty bit state)
 - FEAT_HCX (Support for the HCRX_EL2 register)
 - FEAT_HPDS (Hierarchical permission disables)
+- FEAT_HPDS2 (Translation table page-based hardware attributes)
 - FEAT_I8MM (AArch64 Int8 matrix multiplication instructions)
 - FEAT_IDST (ID space trap handling)
 - FEAT_IESB (Implicit error synchronization event)
diff --git a/target/arm/tcg/cpu32.c b/target/arm/tcg/cpu32.c
index 47d2e8e781..1f918ff537 100644
--- a/target/arm/tcg/cpu32.c
+++ b/target/arm/tcg/cpu32.c
@@ -62,7 +62,7 @@ void aa32_max_features(ARMCPU *cpu)
     cpu->isar.id_mmfr3 = t;
 
     t = cpu->isar.id_mmfr4;
-    t = FIELD_DP32(t, ID_MMFR4, HPDS, 1);         /* FEAT_AA32HPD */
+    t = FIELD_DP32(t, ID_MMFR4, HPDS, 2);         /* FEAT_HPDS2 */
     t = FIELD_DP32(t, ID_MMFR4, AC2, 1);          /* ACTLR2, HACTLR2 */
     t = FIELD_DP32(t, ID_MMFR4, CNP, 1);          /* FEAT_TTCNP */
     t = FIELD_DP32(t, ID_MMFR4, XNX, 1);          /* FEAT_XNX */
diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
index 0054bb6dfa..b12e10d3ab 100644
--- a/target/arm/tcg/cpu64.c
+++ b/target/arm/tcg/cpu64.c
@@ -865,7 +865,7 @@ void aarch64_max_tcg_initfn(Object *obj)
     t = FIELD_DP64(t, ID_AA64MMFR1, HAFDBS, 2);   /* FEAT_HAFDBS */
     t = FIELD_DP64(t, ID_AA64MMFR1, VMIDBITS, 2); /* FEAT_VMID16 */
     t = FIELD_DP64(t, ID_AA64MMFR1, VH, 1);       /* FEAT_VHE */
-    t = FIELD_DP64(t, ID_AA64MMFR1, HPDS, 1);     /* FEAT_HPDS */
+    t = FIELD_DP64(t, ID_AA64MMFR1, HPDS, 2);     /* FEAT_HPDS2 */
     t = FIELD_DP64(t, ID_AA64MMFR1, LO, 1);       /* FEAT_LOR */
     t = FIELD_DP64(t, ID_AA64MMFR1, PAN, 3);      /* FEAT_PAN3 */
     t = FIELD_DP64(t, ID_AA64MMFR1, XNX, 1);      /* FEAT_XNX */
-- 
2.34.1
Re: [PATCH v2 10/11] target/arm: Implement FEAT_HPDS2 as a no-op
Posted by Peter Maydell 2 years, 5 months ago
On Fri, 11 Aug 2023 at 22:41, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> This feature allows the operating system to set TCR_ELx.HWU*
> to allow the implementation to use the PBHA bits from the
> block and page descriptors for for IMPLEMENTATION DEFINED
> purposes.  Since QEMU has no need to use these bits, we may
> simply ignore them.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---

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

thanks
-- PMM