kvm: arm64: Enable hardware updates of the Access Flag for Stage 2 page tables

[karo-tx-linux.git] / arch / arm64 / kvm / hyp / s2-setup.c

diff --git a/arch/arm64/kvm/hyp/s2-setup.c b/arch/arm64/kvm/hyp/s2-setup.c
index bcbe761a5a3d1fa579fb211d89c165ace3b7c5d1..b81f4091c909ce1e2650986648cdde1e2d1a23d0 100644 (file)
--- a/arch/arm64/kvm/hyp/s2-setup.c
+++ b/arch/arm64/kvm/hyp/s2-setup.c
@@ -65,6 +65,14 @@ u32 __hyp_text __init_stage2_translation(void)
         */
        val |= 64 - (parange > 40 ? 40 : parange);
 
+       /*
+        * Check the availability of Hardware Access Flag / Dirty Bit
+        * Management in ID_AA64MMFR1_EL1 and enable the feature in VTCR_EL2.
+        */
+       tmp = (read_sysreg(id_aa64mmfr1_el1) >> ID_AA64MMFR1_HADBS_SHIFT) & 0xf;
+       if (IS_ENABLED(CONFIG_ARM64_HW_AFDBM) && tmp)
+               val |= VTCR_EL2_HA;
+
        /*
         * Read the VMIDBits bits from ID_AA64MMFR1_EL1 and set the VS
         * bit in VTCR_EL2.