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arm64: kvm: 4.6-rc1: Fix VTCR_EL2 VS setting 

When we detect support for 16bit VMID in ID_AA64MMFR1, we set the
VTCR_EL2_VS field to 1 to make use of 16bit vmids. But, with
commit 3a3604bc5e ("arm64: KVM: Switch to C-based stage2 init")
this is broken and we corrupt VTCR_EL2:T0SZ instead of updating the VS
field. VTCR_EL2_VS was actually defined to the field shift (19) and
not the real value for VS. This patch fixes the issue.

Fixes: commit 3a3604bc5e ("arm64: KVM: Switch to C-based stage2 init")
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
hifive-unleashed-5.1
Suzuki K Poulose 2016-03-30 14:33:59 +01:00 committed by Christoffer Dall
parent f55532a0c0
commit cb678d6016
3 changed files with 10 additions and 3 deletions
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4
arch/arm64/include/asm/kvm_arm.h
View File

@ -124,7 +124,9 @@
#define VTCR_EL2_SL0_LVL1 (1 << 6)
#define VTCR_EL2_T0SZ_MASK 0x3f
#define VTCR_EL2_T0SZ_40B 24
#define VTCR_EL2_VS 19
#define VTCR_EL2_VS_SHIFT 19
#define VTCR_EL2_VS_8BIT (0 << VTCR_EL2_VS_SHIFT)
#define VTCR_EL2_VS_16BIT (1 << VTCR_EL2_VS_SHIFT)
/*
* We configure the Stage-2 page tables to always restrict the IPA space to be

3
arch/arm64/include/asm/sysreg.h
View File

@ -141,6 +141,9 @@
#define ID_AA64MMFR1_VMIDBITS_SHIFT 4
#define ID_AA64MMFR1_HADBS_SHIFT 0
#define ID_AA64MMFR1_VMIDBITS_8 0
#define ID_AA64MMFR1_VMIDBITS_16 2
/* id_aa64mmfr2 */
#define ID_AA64MMFR2_UAO_SHIFT 4

6
arch/arm64/kvm/hyp/s2-setup.c
View File

@ -36,8 +36,10 @@ void __hyp_text __init_stage2_translation(void)
* Read the VMIDBits bits from ID_AA64MMFR1_EL1 and set the VS
* bit in VTCR_EL2.
*/
tmp = (read_sysreg(id_aa64mmfr1_el1) >> 4) & 0xf;
val |= (tmp == 2) ? VTCR_EL2_VS : 0;
tmp = (read_sysreg(id_aa64mmfr1_el1) >> ID_AA64MMFR1_VMIDBITS_SHIFT) & 0xf;
val |= (tmp == ID_AA64MMFR1_VMIDBITS_16) ?
VTCR_EL2_VS_16BIT :
VTCR_EL2_VS_8BIT;
write_sysreg(val, vtcr_el2);
}