diff options
Diffstat (limited to 'arch/arm64/kvm/nested.c')
| -rw-r--r-- | arch/arm64/kvm/nested.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c new file mode 100644 index 0000000000..042695a210 --- /dev/null +++ b/arch/arm64/kvm/nested.c @@ -0,0 +1,162 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2017 - Columbia University and Linaro Ltd. + * Author: Jintack Lim <jintack.lim@linaro.org> + */ + +#include <linux/kvm.h> +#include <linux/kvm_host.h> + +#include <asm/kvm_emulate.h> +#include <asm/kvm_nested.h> +#include <asm/sysreg.h> + +#include "sys_regs.h" + +/* Protection against the sysreg repainting madness... */ +#define NV_FTR(r, f) ID_AA64##r##_EL1_##f + +/* + * Our emulated CPU doesn't support all the possible features. For the + * sake of simplicity (and probably mental sanity), wipe out a number + * of feature bits we don't intend to support for the time being. + * This list should get updated as new features get added to the NV + * support, and new extension to the architecture. + */ +void access_nested_id_reg(struct kvm_vcpu *v, struct sys_reg_params *p, + const struct sys_reg_desc *r) +{ + u32 id = reg_to_encoding(r); + u64 val, tmp; + + val = p->regval; + + switch (id) { + case SYS_ID_AA64ISAR0_EL1: + /* Support everything but TME, O.S. and Range TLBIs */ + val &= ~(NV_FTR(ISAR0, TLB) | + NV_FTR(ISAR0, TME)); + break; + + case SYS_ID_AA64ISAR1_EL1: + /* Support everything but PtrAuth and Spec Invalidation */ + val &= ~(GENMASK_ULL(63, 56) | + NV_FTR(ISAR1, SPECRES) | + NV_FTR(ISAR1, GPI) | + NV_FTR(ISAR1, GPA) | + NV_FTR(ISAR1, API) | + NV_FTR(ISAR1, APA)); + break; + + case SYS_ID_AA64PFR0_EL1: + /* No AMU, MPAM, S-EL2, RAS or SVE */ + val &= ~(GENMASK_ULL(55, 52) | + NV_FTR(PFR0, AMU) | + NV_FTR(PFR0, MPAM) | + NV_FTR(PFR0, SEL2) | + NV_FTR(PFR0, RAS) | + NV_FTR(PFR0, SVE) | + NV_FTR(PFR0, EL3) | + NV_FTR(PFR0, EL2) | + NV_FTR(PFR0, EL1)); + /* 64bit EL1/EL2/EL3 only */ + val |= FIELD_PREP(NV_FTR(PFR0, EL1), 0b0001); + val |= FIELD_PREP(NV_FTR(PFR0, EL2), 0b0001); + val |= FIELD_PREP(NV_FTR(PFR0, EL3), 0b0001); + break; + + case SYS_ID_AA64PFR1_EL1: + /* Only support SSBS */ + val &= NV_FTR(PFR1, SSBS); + break; + + case SYS_ID_AA64MMFR0_EL1: + /* Hide ECV, ExS, Secure Memory */ + val &= ~(NV_FTR(MMFR0, ECV) | + NV_FTR(MMFR0, EXS) | + NV_FTR(MMFR0, TGRAN4_2) | + NV_FTR(MMFR0, TGRAN16_2) | + NV_FTR(MMFR0, TGRAN64_2) | + NV_FTR(MMFR0, SNSMEM)); + + /* Disallow unsupported S2 page sizes */ + switch (PAGE_SIZE) { + case SZ_64K: + val |= FIELD_PREP(NV_FTR(MMFR0, TGRAN16_2), 0b0001); + fallthrough; + case SZ_16K: + val |= FIELD_PREP(NV_FTR(MMFR0, TGRAN4_2), 0b0001); + fallthrough; + case SZ_4K: + /* Support everything */ + break; + } + /* + * Since we can't support a guest S2 page size smaller than + * the host's own page size (due to KVM only populating its + * own S2 using the kernel's page size), advertise the + * limitation using FEAT_GTG. + */ + switch (PAGE_SIZE) { + case SZ_4K: + val |= FIELD_PREP(NV_FTR(MMFR0, TGRAN4_2), 0b0010); + fallthrough; + case SZ_16K: + val |= FIELD_PREP(NV_FTR(MMFR0, TGRAN16_2), 0b0010); + fallthrough; + case SZ_64K: + val |= FIELD_PREP(NV_FTR(MMFR0, TGRAN64_2), 0b0010); + break; + } + /* Cap PARange to 48bits */ + tmp = FIELD_GET(NV_FTR(MMFR0, PARANGE), val); + if (tmp > 0b0101) { + val &= ~NV_FTR(MMFR0, PARANGE); + val |= FIELD_PREP(NV_FTR(MMFR0, PARANGE), 0b0101); + } + break; + + case SYS_ID_AA64MMFR1_EL1: + val &= (NV_FTR(MMFR1, HCX) | + NV_FTR(MMFR1, PAN) | + NV_FTR(MMFR1, LO) | + NV_FTR(MMFR1, HPDS) | + NV_FTR(MMFR1, VH) | + NV_FTR(MMFR1, VMIDBits)); + break; + + case SYS_ID_AA64MMFR2_EL1: + val &= ~(NV_FTR(MMFR2, BBM) | + NV_FTR(MMFR2, TTL) | + GENMASK_ULL(47, 44) | + NV_FTR(MMFR2, ST) | + NV_FTR(MMFR2, CCIDX) | + NV_FTR(MMFR2, VARange)); + + /* Force TTL support */ + val |= FIELD_PREP(NV_FTR(MMFR2, TTL), 0b0001); + break; + + case SYS_ID_AA64DFR0_EL1: + /* Only limited support for PMU, Debug, BPs and WPs */ + val &= (NV_FTR(DFR0, PMUVer) | + NV_FTR(DFR0, WRPs) | + NV_FTR(DFR0, BRPs) | + NV_FTR(DFR0, DebugVer)); + + /* Cap Debug to ARMv8.1 */ + tmp = FIELD_GET(NV_FTR(DFR0, DebugVer), val); + if (tmp > 0b0111) { + val &= ~NV_FTR(DFR0, DebugVer); + val |= FIELD_PREP(NV_FTR(DFR0, DebugVer), 0b0111); + } + break; + + default: + /* Unknown register, just wipe it clean */ + val = 0; + break; + } + + p->regval = val; +} |