Subject: [PATCH v3 07/17] arm64: Use CPACR_EL1 format to set CPTR_EL2 when E2H is set

From: Marc Zyngier <[email-masked]>
Date: Fri, 9 Jun 2023 17:21:50 +0100

When HCR_EL2.E2H is set, the CPTR_EL2 register takes the CPACR_EL1
format. Yes, this is good fun.

Hack the bits of startup code that assume E2H=0 while setting up
CPTR_EL2 to make them grok the CPTR_EL1 format.

Signed-off-by: Marc Zyngier <[email-masked]>
---
 arch/arm64/include/asm/el2_setup.h | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index 225bf1f2514d..bba508ffa12d 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -129,8 +129,15 @@
 .endm
 
 /* Coprocessor traps */
-.macro __init_el2_nvhe_cptr
+.macro __init_el2_cptr
+	mrs	x1, hcr_el2
+	and	x1, x1, #HCR_E2H
+	cbz	x1, .LnVHE_\@
+	mov	x0, #(CPACR_EL1_FPEN_EL1EN | CPACR_EL1_FPEN_EL0EN)
+	b	.Lset_cptr_\@
+.LnVHE_\@:
 	mov	x0, #0x33ff
+.Lset_cptr_\@:
 	msr	cptr_el2, x0			// Disable copro. traps to EL2
 .endm
 
@@ -196,7 +203,7 @@
 	__init_el2_gicv3
 	__init_el2_hstr
 	__init_el2_nvhe_idregs
-	__init_el2_nvhe_cptr
+	__init_el2_cptr
 	__init_el2_fgt
 	__init_el2_nvhe_prepare_eret
 .endm
@@ -244,7 +251,17 @@
 
 .Linit_sve_\@:	/* SVE register access */
 	mrs	x0, cptr_el2			// Disable SVE traps
+	mrs	x1, hcr_el2
+	and	x1, x1, #HCR_E2H
+	cbz	x1, .Lcptr_nvhe_\@
+
+	// VHE case
+	orr	x0, x0, #(CPACR_EL1_ZEN_EL1EN | CPACR_EL1_ZEN_EL0EN)
+	b	.Lset_cptr_\@
+
+.Lcptr_nvhe_\@: // nVHE case
 	bic	x0, x0, #CPTR_EL2_TZ
+.Lset_cptr_\@:
 	msr	cptr_el2, x0
 	isb
 	mov	x1, #ZCR_ELx_LEN_MASK		// SVE: Enable full vector
-- 
2.34.1

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