[PATCH] Documentation (arm64):Advanced SIMD and floating point support condition

[Xiquan Zhang]

From: zhangyu <zhangyu550@xxxxxxxxxx>

Because the kernel code cannot be started from el1
according to the booting.rst.
It is found that CPTR_EL2.FPEN is not configured.
After the configuration, the problem is solved.

Signed-off-by: zhangyu <zhangyu550@xxxxxxxxxx>
Signed-off-by: zhangxiquan <zhangxiquan@xxxxxxxxxxxxx>
---
 Documentation/arch/arm64/booting.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/arch/arm64/booting.rst b/Documentation/arch/arm64/booting.rst
index dee7b6de864f..ccefc42b51bc 100644
--- a/Documentation/arch/arm64/booting.rst
+++ b/Documentation/arch/arm64/booting.rst
@@ -309,6 +309,7 @@ Before jumping into the kernel, the following conditions must be met:
   - If EL2 is present and the kernel is entered at EL1:

     - CPTR_EL2.TFP (bit 10) must be initialised to 0b0.
+    - CPTR_EL2.FPEN (bit 21:20) must be initialised to 0b11.

   For CPUs with the Scalable Vector Extension (FEAT_SVE) present:

--
2.45.1.windows.1