On 31/03/2025 10:43, Yicong Yang wrote:
From: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
Instructions introduced by FEAT_{LS64, LS64_V} is controlled by
HCRX_EL2.{EnALS, EnASR}. Configure all of these to allow usage
at EL0/1.
This doesn't mean these instructions are always available in
EL0/1 if provided. The hypervisor still have the control at
runtime.
Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
---
arch/arm64/include/asm/el2_setup.h | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index ebceaae3c749..0259941602c4 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -57,9 +57,19 @@
/* Enable GCS if supported */
mrs_s x1, SYS_ID_AA64PFR1_EL1
ubfx x1, x1, #ID_AA64PFR1_EL1_GCS_SHIFT, #4
- cbz x1, .Lset_hcrx_\@
+ cbz x1, .Lskip_gcs_hcrx_\@
orr x0, x0, #HCRX_EL2_GCSEn
+.Lskip_gcs_hcrx_\@:
minor nit: For consistency, could we rename this "set_ls64", similar to
"set_hcrx" ?
+ /* Enable LS64, LS64_V if supported */
+ mrs_s x1, SYS_ID_AA64ISAR1_EL1
+ ubfx x1, x1, #ID_AA64ISAR1_EL1_LS64_SHIFT, #4
+ cbz x1, .Lset_hcrx_\@
+ orr x0, x0, #HCRX_EL2_EnALS
+ cmp x1, #ID_AA64ISAR1_EL1_LS64_LS64_V
+ b.lt .Lset_hcrx_\@
+ orr x0, x0, #HCRX_EL2_EnASR
+
.Lset_hcrx_\@:
msr_s SYS_HCRX_EL2, x0
.Lskip_hcrx_\@:
Suzuki
