[PATCH v2 05/21] arm64: KVM: VHE: Turn VTCR_EL2 setup into a reusable macro

From: Marc Zyngier
Date: Mon Jan 25 2016 - 10:54:51 EST


On a VHE-capable system, there is no point in setting VTCR_EL2
at KVM init time. We can perfectly set it up when the kernel
boots, removing the need for a more complicated configuration.

In order to allow this, turn VTCR_EL2 setup into a macro that
we'll be able to reuse at boot time.

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
arch/arm64/include/asm/kvm_mmu.h | 23 +++++++++++++++++++++++
arch/arm64/kvm/hyp-init.S | 18 +-----------------
2 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 7364339..d3e6d7b 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -56,6 +56,29 @@

#ifdef __ASSEMBLY__

+#include <asm/kvm_arm.h>
+
+.macro setup_vtcr tmp1, tmp2
+ mov \tmp1, #(VTCR_EL2_FLAGS & 0xffff)
+ movk \tmp1, #(VTCR_EL2_FLAGS >> 16), lsl #16
+ /*
+ * Read the PARange bits from ID_AA64MMFR0_EL1 and set the PS bits in
+ * VTCR_EL2.
+ */
+ mrs \tmp2, id_aa64mmfr0_el1
+ bfi \tmp1, \tmp2, #16, #3
+ /*
+ * Read the VMIDBits bits from ID_AA64MMFR1_EL1 and set the VS bit in
+ * VTCR_EL2.
+ */
+ mrs \tmp2, ID_AA64MMFR1_EL1
+ ubfx \tmp2, \tmp2, #5, #1
+ lsl \tmp2, \tmp2, #VTCR_EL2_VS
+ orr \tmp1, \tmp1, \tmp2
+
+ msr vtcr_el2, \tmp1
+ isb
+.endm
/*
* Convert a kernel VA into a HYP VA.
* reg: VA to be converted.
diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S
index 3e568dc..4143e2c 100644
--- a/arch/arm64/kvm/hyp-init.S
+++ b/arch/arm64/kvm/hyp-init.S
@@ -87,23 +87,7 @@ __do_hyp_init:
#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.
- */
- mrs x5, ID_AA64MMFR0_EL1
- bfi x4, x5, #16, #3
- /*
- * Read the VMIDBits bits from ID_AA64MMFR1_EL1 and set the VS bit in
- * VTCR_EL2.
- */
- mrs x5, ID_AA64MMFR1_EL1
- ubfx x5, x5, #5, #1
- lsl x5, x5, #VTCR_EL2_VS
- orr x4, x4, x5
-
- msr vtcr_el2, x4
+ setup_vtcr x4, x5

mrs x4, mair_el1
msr mair_el2, x4
--
2.1.4