[PATCH V2] arm64: KVM: Configure TCR_EL2.ps at runtime

[tchalamarla at caviumnetworks.com]

From: Tirumalesh Chalamarla <tchalamarla at caviumnetworks.com>

Setting TCR_EL2.ps to 40 bits is wrong on systems with ps size is
less than 40 bits. and with systems where RAM is at higher address,
this will break KVM.

This patch sets TCR_EL2.ps at runtime similar to VTCR_EL.ps

Signed-off-by: Tirumalesh Chalamarla <tchalamarla at caviumnetworks.com>
---
 arch/arm64/include/asm/kvm_arm.h |  5 ++++-
 arch/arm64/kvm/hyp-init.S        | 10 ++++++----
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index 738a95f..92f2ffd 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -107,7 +107,10 @@
 #define TCR_EL2_MASK	(TCR_EL2_TG0 | TCR_EL2_SH0 | \
 			 TCR_EL2_ORGN0 | TCR_EL2_IRGN0 | TCR_EL2_T0SZ)
 
-#define TCR_EL2_FLAGS	(TCR_EL2_RES1 | TCR_EL2_PS_40B)
+/*
+ * TCR_EL2.ps is configured at runtime similar to VTCR_EL2
+ */
+#define TCR_EL2_FLAGS	(TCR_EL2_RES1)
 
 /* VTCR_EL2 Registers bits */
 #define VTCR_EL2_RES1		(1 << 31)
diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S
index 3e568dc..b246de1e 100644
--- a/arch/arm64/kvm/hyp-init.S
+++ b/arch/arm64/kvm/hyp-init.S
@@ -85,15 +85,17 @@ __do_hyp_init:
 	ldr_l	x5, idmap_t0sz
 	bfi	x4, x5, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH
 #endif
-	msr	tcr_el2, x4
-
-	ldr	x4, =VTCR_EL2_FLAGS
 	/*
 	 * Read the PARange bits from ID_AA64MMFR0_EL1 and set the PS bits in
-	 * VTCR_EL2.
+	 * TCR_EL2 and VTCR_EL2.
 	 */
 	mrs	x5, ID_AA64MMFR0_EL1
 	bfi	x4, x5, #16, #3
+
+	msr	tcr_el2, x4
+
+	ldr	x4, =VTCR_EL2_FLAGS
+	bfi	x4, x5, #16, #3
 	/*
 	 * Read the VMIDBits bits from ID_AA64MMFR1_EL1 and set the VS bit in
 	 * VTCR_EL2.
-- 
2.1.0