[PATCH v3 15/25] arm64: Disable GICv5 read/write/instruction traps

Lorenzo Pieralisi lpieralisi at kernel.org
Tue May 6 05:23:44 PDT 2025


GICv5 trap configuration registers value is UNKNOWN at reset.

Initialize GICv5 EL2 trap configuration registers to prevent
trapping GICv5 instruction/register access upon entering the
kernel.

Signed-off-by: Lorenzo Pieralisi <lpieralisi at kernel.org>
Cc: Will Deacon <will at kernel.org>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Marc Zyngier <maz at kernel.org>
---
 arch/arm64/include/asm/el2_setup.h | 45 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index ebceaae3c749b84395c9c5eccf0caf874697ad11..109b72b657d2fbb6d39e0446c10d1b62e0a780b3 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -165,6 +165,50 @@
 .Lskip_gicv3_\@:
 .endm
 
+/* GICv5 system register access */
+.macro __init_el2_gicv5
+	mrs_s	x0, SYS_ID_AA64PFR2_EL1
+	ubfx	x0, x0, #ID_AA64PFR2_EL1_GCIE_SHIFT, #4
+	cbz	x0, .Lskip_gicv5_\@
+
+	mov	x0, #(ICH_HFGITR_EL2_GICRCDNMIA		| \
+		      ICH_HFGITR_EL2_GICRCDIA		| \
+		      ICH_HFGITR_EL2_GICCDDI		| \
+		      ICH_HFGITR_EL2_GICCDEOI		| \
+		      ICH_HFGITR_EL2_GICCDHM		| \
+		      ICH_HFGITR_EL2_GICCRDRCFG		| \
+		      ICH_HFGITR_EL2_GICCDPEND		| \
+		      ICH_HFGITR_EL2_GICCDAFF		| \
+		      ICH_HFGITR_EL2_GICCDPRI		| \
+		      ICH_HFGITR_EL2_GICCDDIS		| \
+		      ICH_HFGITR_EL2_GICCDEN)
+	msr_s	SYS_ICH_HFGITR_EL2, x0		// Disable instruction traps
+	mov_q	x0, (ICH_HFGRTR_EL2_ICC_PPI_ACTIVERn_EL1	| \
+		     ICH_HFGRTR_EL2_ICC_PPI_PRIORITYRn_EL1	| \
+		     ICH_HFGRTR_EL2_ICC_PPI_PENDRn_EL1		| \
+		     ICH_HFGRTR_EL2_ICC_PPI_ENABLERn_EL1	| \
+		     ICH_HFGRTR_EL2_ICC_PPI_HMRn_EL1		| \
+		     ICH_HFGRTR_EL2_ICC_IAFFIDR_EL1		| \
+		     ICH_HFGRTR_EL2_ICC_ICSR_EL1		| \
+		     ICH_HFGRTR_EL2_ICC_PCR_EL1			| \
+		     ICH_HFGRTR_EL2_ICC_HPPIR_EL1		| \
+		     ICH_HFGRTR_EL2_ICC_HAPR_EL1		| \
+		     ICH_HFGRTR_EL2_ICC_CR0_EL1			| \
+		     ICH_HFGRTR_EL2_ICC_IDRn_EL1		| \
+		     ICH_HFGRTR_EL2_ICC_APR_EL1)
+	msr_s	SYS_ICH_HFGRTR_EL2, x0		// Disable reg read traps
+	mov_q	x0, (ICH_HFGWTR_EL2_ICC_PPI_ACTIVERn_EL1	| \
+		     ICH_HFGWTR_EL2_ICC_PPI_PRIORITYRn_EL1	| \
+		     ICH_HFGWTR_EL2_ICC_PPI_PENDRn_EL1		| \
+		     ICH_HFGWTR_EL2_ICC_PPI_ENABLERn_EL1	| \
+		     ICH_HFGWTR_EL2_ICC_ICSR_EL1		| \
+		     ICH_HFGWTR_EL2_ICC_PCR_EL1			| \
+		     ICH_HFGWTR_EL2_ICC_CR0_EL1			| \
+		     ICH_HFGWTR_EL2_ICC_APR_EL1)
+	msr_s	SYS_ICH_HFGWTR_EL2, x0		// Disable reg write traps
+.Lskip_gicv5_\@:
+.endm
+
 .macro __init_el2_hstr
 	msr	hstr_el2, xzr			// Disable CP15 traps to EL2
 .endm
@@ -323,6 +367,7 @@
 	__init_el2_lor
 	__init_el2_stage2
 	__init_el2_gicv3
+	__init_el2_gicv5
 	__init_el2_hstr
 	__init_el2_mpam
 	__init_el2_nvhe_idregs

-- 
2.48.0




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