[PATCH v4 04/29] arm64: disable trapping of POR_EL0 to EL2

Joey Gouly joey.gouly at arm.com
Fri May 3 23:01:22 AEST 2024


Allow EL0 or EL1 to access POR_EL0 without being trapped to EL2.

Signed-off-by: Joey Gouly <joey.gouly at arm.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will at kernel.org>
Acked-by: Catalin Marinas <catalin.marinas at arm.com>
---
 arch/arm64/include/asm/el2_setup.h | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index b7afaa026842..df5614be4b70 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -184,12 +184,20 @@
 .Lset_pie_fgt_\@:
 	mrs_s	x1, SYS_ID_AA64MMFR3_EL1
 	ubfx	x1, x1, #ID_AA64MMFR3_EL1_S1PIE_SHIFT, #4
-	cbz	x1, .Lset_fgt_\@
+	cbz	x1, .Lset_poe_fgt_\@
 
 	/* Disable trapping of PIR_EL1 / PIRE0_EL1 */
 	orr	x0, x0, #HFGxTR_EL2_nPIR_EL1
 	orr	x0, x0, #HFGxTR_EL2_nPIRE0_EL1
 
+.Lset_poe_fgt_\@:
+	mrs_s	x1, SYS_ID_AA64MMFR3_EL1
+	ubfx	x1, x1, #ID_AA64MMFR3_EL1_S1POE_SHIFT, #4
+	cbz	x1, .Lset_fgt_\@
+
+	/* Disable trapping of POR_EL0 */
+	orr	x0, x0, #HFGxTR_EL2_nPOR_EL0
+
 .Lset_fgt_\@:
 	msr_s	SYS_HFGRTR_EL2, x0
 	msr_s	SYS_HFGWTR_EL2, x0
-- 
2.25.1



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