[PATCH v4 16/20] arm64: enable Permission Indirection Extension (PIE)

[Joey Gouly]

Now that the necessary changes have been made, set the Permission Indirection
registers and enable the Permission Indirection Extension.

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>
Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>
---
 arch/arm64/mm/proc.S | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 9513a8d2ce0e..2baeec419f62 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -454,6 +454,21 @@ SYM_FUNC_START(__cpu_setup)
 #endif	/* CONFIG_ARM64_HW_AFDBM */
 	msr	mair_el1, mair
 	msr	tcr_el1, tcr
+
+	mrs_s	x1, SYS_ID_AA64MMFR3_EL1
+	ubfx	x1, x1, #ID_AA64MMFR3_EL1_S1PIE_SHIFT, #4
+	cbz	x1, .Lskip_indirection
+
+	mov_q	x0, PIE_E0
+	msr	REG_PIRE0_EL1, x0
+	mov_q	x0, PIE_E1
+	msr	REG_PIR_EL1, x0
+
+	mov	x0, TCR2_EL1x_PIE
+	msr	REG_TCR2_EL1, x0
+
+.Lskip_indirection:
+
 	/*
 	 * Prepare SCTLR
 	 */
-- 
2.25.1