KVM: arm64: Handle HAFGRTR_EL2 trapping in nested virt

Add the encodings to fine grain trapping fields for HAFGRTR_EL2
and add the associated handling code in nested virt. Based on
DDI0601 2023-09. Add the missing field definitions as well,
both to generate the correct RES0 mask and to be able to toggle
their FGT bits.

Also add the code for handling FGT trapping, reading of the
register, to nested virt.

Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-10-tabba@google.com

4 files changed, 75 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 824f29f04916..ba14648e2de2 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -443,6 +443,7 @@ enum vcpu_sysreg {
 	HFGITR_EL2,
 	HDFGRTR_EL2,
 	HDFGWTR_EL2,
+	HAFGRTR_EL2,
 	CNTHP_CTL_EL2,
 	CNTHP_CVAL_EL2,
 	CNTHV_CTL_EL2,
diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c
index 89901550db34..431fd429932d 100644
--- a/arch/arm64/kvm/emulate-nested.c
+++ b/arch/arm64/kvm/emulate-nested.c
@@ -1012,6 +1012,7 @@ enum fgt_group_id {
 	HDFGRTR_GROUP,
 	HDFGWTR_GROUP,
 	HFGITR_GROUP,
+	HAFGRTR_GROUP,
 
 	/* Must be last */
 	__NR_FGT_GROUP_IDS__
@@ -1689,6 +1690,49 @@ static const struct encoding_to_trap_config encoding_to_fgt[] __initconst = {
 	SR_FGT(SYS_PMCR_EL0,		HDFGWTR, PMCR_EL0, 1),
 	SR_FGT(SYS_PMSWINC_EL0,		HDFGWTR, PMSWINC_EL0, 1),
 	SR_FGT(SYS_OSLAR_EL1,		HDFGWTR, OSLAR_EL1, 1),
+	/*
+	 * HAFGRTR_EL2
+	 */
+	SR_FGT(SYS_AMEVTYPER1_EL0(15),	HAFGRTR, AMEVTYPER115_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(14),	HAFGRTR, AMEVTYPER114_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(13),	HAFGRTR, AMEVTYPER113_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(12),	HAFGRTR, AMEVTYPER112_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(11),	HAFGRTR, AMEVTYPER111_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(10),	HAFGRTR, AMEVTYPER110_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(9),	HAFGRTR, AMEVTYPER19_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(8),	HAFGRTR, AMEVTYPER18_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(7),	HAFGRTR, AMEVTYPER17_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(6),	HAFGRTR, AMEVTYPER16_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(5),	HAFGRTR, AMEVTYPER15_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(4),	HAFGRTR, AMEVTYPER14_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(3),	HAFGRTR, AMEVTYPER13_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(2),	HAFGRTR, AMEVTYPER12_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(1),	HAFGRTR, AMEVTYPER11_EL0, 1),
+	SR_FGT(SYS_AMEVTYPER1_EL0(0),	HAFGRTR, AMEVTYPER10_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(15),	HAFGRTR, AMEVCNTR115_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(14),	HAFGRTR, AMEVCNTR114_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(13),	HAFGRTR, AMEVCNTR113_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(12),	HAFGRTR, AMEVCNTR112_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(11),	HAFGRTR, AMEVCNTR111_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(10),	HAFGRTR, AMEVCNTR110_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(9),	HAFGRTR, AMEVCNTR19_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(8),	HAFGRTR, AMEVCNTR18_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(7),	HAFGRTR, AMEVCNTR17_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(6),	HAFGRTR, AMEVCNTR16_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(5),	HAFGRTR, AMEVCNTR15_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(4),	HAFGRTR, AMEVCNTR14_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(3),	HAFGRTR, AMEVCNTR13_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(2),	HAFGRTR, AMEVCNTR12_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(1),	HAFGRTR, AMEVCNTR11_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR1_EL0(0),	HAFGRTR, AMEVCNTR10_EL0, 1),
+	SR_FGT(SYS_AMCNTENCLR1_EL0,	HAFGRTR, AMCNTEN1, 1),
+	SR_FGT(SYS_AMCNTENSET1_EL0,	HAFGRTR, AMCNTEN1, 1),
+	SR_FGT(SYS_AMCNTENCLR0_EL0,	HAFGRTR, AMCNTEN0, 1),
+	SR_FGT(SYS_AMCNTENSET0_EL0,	HAFGRTR, AMCNTEN0, 1),
+	SR_FGT(SYS_AMEVCNTR0_EL0(3),	HAFGRTR, AMEVCNTR03_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR0_EL0(2),	HAFGRTR, AMEVCNTR02_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR0_EL0(1),	HAFGRTR, AMEVCNTR01_EL0, 1),
+	SR_FGT(SYS_AMEVCNTR0_EL0(0),	HAFGRTR, AMEVCNTR00_EL0, 1),
 };
 
 static union trap_config get_trap_config(u32 sysreg)
@@ -1909,6 +1953,10 @@ bool __check_nv_sr_forward(struct kvm_vcpu *vcpu)
 			val = sanitised_sys_reg(vcpu, HDFGWTR_EL2);
 		break;
 
+	case HAFGRTR_GROUP:
+		val = sanitised_sys_reg(vcpu, HAFGRTR_EL2);
+		break;
+
 	case HFGITR_GROUP:
 		val = sanitised_sys_reg(vcpu, HFGITR_EL2);
 		switch (tc.fgf) {
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index 7b4909dfd1f5..0436f0da98a4 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -80,6 +80,14 @@ static inline void __activate_traps_fpsimd32(struct kvm_vcpu *vcpu)
 	} while(0)
 
 
+static inline bool cpu_has_amu(void)
+{
+       u64 pfr0 = read_sysreg_s(SYS_ID_AA64PFR0_EL1);
+
+       return cpuid_feature_extract_unsigned_field(pfr0,
+               ID_AA64PFR0_EL1_AMU_SHIFT);
+}
+
 static inline void __activate_traps_hfgxtr(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpu_context *hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
@@ -156,6 +164,20 @@ static inline void __activate_traps_hfgxtr(struct kvm_vcpu *vcpu)
 
 	write_sysreg_s(r_val, SYS_HDFGRTR_EL2);
 	write_sysreg_s(w_val, SYS_HDFGWTR_EL2);
+
+       if (!cpu_has_amu())
+               return;
+
+	ctxt_sys_reg(hctxt, HAFGRTR_EL2) = read_sysreg_s(SYS_HAFGRTR_EL2);
+
+	r_clr = r_set = 0;
+	compute_clr_set(vcpu, HAFGRTR_EL2, r_clr, r_set);
+
+	r_val = __HAFGRTR_EL2_nMASK;
+	r_val |= r_set;
+	r_val &= ~r_clr;
+
+	write_sysreg_s(r_val, SYS_HAFGRTR_EL2);
 }
 
 static inline void __deactivate_traps_hfgxtr(struct kvm_vcpu *vcpu)
@@ -174,6 +196,9 @@ static inline void __deactivate_traps_hfgxtr(struct kvm_vcpu *vcpu)
 	write_sysreg_s(ctxt_sys_reg(hctxt, HFGITR_EL2), SYS_HFGITR_EL2);
 	write_sysreg_s(ctxt_sys_reg(hctxt, HDFGRTR_EL2), SYS_HDFGRTR_EL2);
 	write_sysreg_s(ctxt_sys_reg(hctxt, HDFGWTR_EL2), SYS_HDFGWTR_EL2);
+
+	if (vcpu_has_amu())
+		write_sysreg_s(ctxt_sys_reg(hctxt, HAFGRTR_EL2), SYS_HAFGRTR_EL2);
 }
 
 static inline void __activate_traps_common(struct kvm_vcpu *vcpu)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 4735e1b37fb3..8bb297a2df38 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -2532,6 +2532,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 	{ SYS_DESC(SYS_DACR32_EL2), trap_undef, reset_unknown, DACR32_EL2 },
 	EL2_REG(HDFGRTR_EL2, access_rw, reset_val, 0),
 	EL2_REG(HDFGWTR_EL2, access_rw, reset_val, 0),
+	EL2_REG(HAFGRTR_EL2, access_rw, reset_val, 0),
 	EL2_REG(SPSR_EL2, access_rw, reset_val, 0),
 	EL2_REG(ELR_EL2, access_rw, reset_val, 0),
 	{ SYS_DESC(SYS_SP_EL1), access_sp_el1},