diff options
Diffstat (limited to 'arch/arm64/kvm/hyp-init.S')
| -rw-r--r-- | arch/arm64/kvm/hyp-init.S | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S index c3191168a994..178ba2248a98 100644 --- a/arch/arm64/kvm/hyp-init.S +++ b/arch/arm64/kvm/hyp-init.S @@ -20,6 +20,7 @@ #include <asm/assembler.h> #include <asm/kvm_arm.h> #include <asm/kvm_mmu.h> +#include <asm/pgtable-hwdef.h> .text .pushsection .hyp.idmap.text, "ax" @@ -65,6 +66,25 @@ __do_hyp_init: and x4, x4, x5 ldr x5, =TCR_EL2_FLAGS orr x4, x4, x5 + +#ifndef CONFIG_ARM64_VA_BITS_48 + /* + * If we are running with VA_BITS < 48, we may be running with an extra + * level of translation in the ID map. This is only the case if system + * RAM is out of range for the currently configured page size and number + * of translation levels, in which case we will also need the extra + * level for the HYP ID map, or we won't be able to enable the EL2 MMU. + * + * However, at EL2, there is only one TTBR register, and we can't switch + * between translation tables *and* update TCR_EL2.T0SZ at the same + * time. Bottom line: we need the extra level in *both* our translation + * tables. + * + * So use the same T0SZ value we use for the ID map. + */ + ldr_l x5, idmap_t0sz + bfi x4, x5, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH +#endif msr tcr_el2, x4 ldr x4, =VTCR_EL2_FLAGS @@ -91,6 +111,10 @@ __do_hyp_init: msr sctlr_el2, x4 isb + /* Skip the trampoline dance if we merged the boot and runtime PGDs */ + cmp x0, x1 + b.eq merged + /* MMU is now enabled. Get ready for the trampoline dance */ ldr x4, =TRAMPOLINE_VA adr x5, target @@ -105,6 +129,7 @@ target: /* We're now in the trampoline code, switch page tables */ tlbi alle2 dsb sy +merged: /* Set the stack and new vectors */ kern_hyp_va x2 mov sp, x2 |