diff mbox series

docs/system/arm: Document FEAT_RME

Message ID 20230622143046.1578160-1-richard.henderson@linaro.org
State Accepted
Commit 57223a4c24d58493d1eade8c1b38fd707f845d5e
Headers show
Series docs/system/arm: Document FEAT_RME | expand

Commit Message

Richard Henderson June 22, 2023, 2:30 p.m. UTC
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 docs/system/arm/cpu-features.rst | 23 +++++++++++++++++++++++
 docs/system/arm/emulation.rst    |  1 +
 2 files changed, 24 insertions(+)

Comments

Alex Bennée June 22, 2023, 3:50 p.m. UTC | #1
Richard Henderson <richard.henderson@linaro.org> writes:

> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Peter Maydell June 23, 2023, 10:21 a.m. UTC | #2
On Thu, 22 Jun 2023 at 15:30, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  docs/system/arm/cpu-features.rst | 23 +++++++++++++++++++++++
>  docs/system/arm/emulation.rst    |  1 +
>  2 files changed, 24 insertions(+)
>
> diff --git a/docs/system/arm/cpu-features.rst b/docs/system/arm/cpu-features.rst
> index f4524b6d3e..741bf3a299 100644
> --- a/docs/system/arm/cpu-features.rst
> +++ b/docs/system/arm/cpu-features.rst
> @@ -435,3 +435,26 @@ As with ``sve-default-vector-length``, if the default length is larger
>  than the maximum vector length enabled, the actual vector length will
>  be reduced.  If this property is set to ``-1`` then the default vector
>  length is set to the maximum possible length.
> +
> +RME CPU Properties
> +==================
> +
> +The status of RME support with QEMU is experimental.  At this time We

I fixed the capital 'W' here...

> +only support RME within the CPU proper, not within the SMMU or GIC.
> +The feature is enabled by the CPU property ``x-rme``, with the ``x-``
> +prefix present as a reminder of the experimental status, and defaults off.


> --- a/docs/system/arm/emulation.rst
> +++ b/docs/system/arm/emulation.rst
> @@ -66,6 +66,7 @@ the following architecture extensions:
>  - FEAT_RAS (Reliability, availability, and serviceability)
>  - FEAT_RASv1p1 (RAS Extension v1.1)
>  - FEAT_RDM (Advanced SIMD rounding double multiply accumulate instructions)
> +- FEAT_RME (Realm Management Extension)

...and added "(NB: support status in QEMU is experimental)"
to this line, and have applied it to target-arm.next; thanks.

-- PMM
diff mbox series

Patch

diff --git a/docs/system/arm/cpu-features.rst b/docs/system/arm/cpu-features.rst
index f4524b6d3e..741bf3a299 100644
--- a/docs/system/arm/cpu-features.rst
+++ b/docs/system/arm/cpu-features.rst
@@ -435,3 +435,26 @@  As with ``sve-default-vector-length``, if the default length is larger
 than the maximum vector length enabled, the actual vector length will
 be reduced.  If this property is set to ``-1`` then the default vector
 length is set to the maximum possible length.
+
+RME CPU Properties
+==================
+
+The status of RME support with QEMU is experimental.  At this time We
+only support RME within the CPU proper, not within the SMMU or GIC.
+The feature is enabled by the CPU property ``x-rme``, with the ``x-``
+prefix present as a reminder of the experimental status, and defaults off.
+
+The method for enabling RME will change in some future QEMU release
+without notice or backward compatibility.
+
+RME Level 0 GPT Size Property
+-----------------------------
+
+To aid firmware developers in testing different possible CPU
+configurations, ``x-l0gptsz=S`` may be used to specify the value
+to encode into ``GPCCR_EL3.L0GPTSZ``, a read-only field that
+specifies the size of the Level 0 Granule Protection Table.
+Legal values for ``S`` are 30, 34, 36, and 39; the default is 30.
+
+As with ``x-rme``, the ``x-l0gptsz`` property may be renamed or
+removed in some future QEMU release.
diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst
index ecbbd63adf..b54718a867 100644
--- a/docs/system/arm/emulation.rst
+++ b/docs/system/arm/emulation.rst
@@ -66,6 +66,7 @@  the following architecture extensions:
 - FEAT_RAS (Reliability, availability, and serviceability)
 - FEAT_RASv1p1 (RAS Extension v1.1)
 - FEAT_RDM (Advanced SIMD rounding double multiply accumulate instructions)
+- FEAT_RME (Realm Management Extension)
 - FEAT_RNG (Random number generator)
 - FEAT_S2FWB (Stage 2 forced Write-Back)
 - FEAT_SB (Speculation Barrier)