As we're about to majorly extend the handling of FGT registers,
restructure the code to actually save/restore the registers
as required. This is made easy thanks to the previous addition
of the EL2 registers, allowing us to use the host context for
this purpose.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_arm.h | 21 ++++++++++
arch/arm64/kvm/hyp/include/hyp/switch.h | 56 +++++++++++++------------
2 files changed, 50 insertions(+), 27 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index 028049b147df..85908aa18908 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -333,6 +333,27 @@
BIT(18) | \
GENMASK(16, 15))
+/*
+ * FGT register definitions
+ *
+ * RES0 and polarity masks as of DDI0487J.a, to be updated as needed.
+ * We're not using the generated masks as they are usually ahead of
+ * the published ARM ARM, which we use as a reference.
+ *
+ * Once we get to a point where the two describe the same thing, we'll
+ * merge the definitions. One day.
+ */
+#define __HFGRTR_EL2_RES0 (GENMASK(63, 56) | GENMASK(53, 51))
+#define __HFGRTR_EL2_MASK GENMASK(49, 0)
+#define __HFGRTR_EL2_nMASK (GENMASK(55, 54) | BIT(50))
+
+#define __HFGWTR_EL2_RES0 (GENMASK(63, 56) | GENMASK(53, 51) | \
+ BIT(46) | BIT(42) | BIT(40) | BIT(28) | \
+ GENMASK(26, 25) | BIT(21) | BIT(18) | \
+ GENMASK(15, 14) | GENMASK(10, 9) | BIT(2))
+#define __HFGWTR_EL2_MASK GENMASK(49, 0)
+#define __HFGWTR_EL2_nMASK (GENMASK(55, 54) | BIT(50))
+
/* Hyp Prefetch Fault Address Register (HPFAR/HDFAR) */
#define HPFAR_MASK (~UL(0xf))
/*
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index 4bddb8541bec..966295178aee 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -70,20 +70,19 @@ static inline void __activate_traps_fpsimd32(struct kvm_vcpu *vcpu)
}
}
-static inline bool __hfgxtr_traps_required(void)
-{
- if (cpus_have_final_cap(ARM64_SME))
- return true;
-
- if (cpus_have_final_cap(ARM64_WORKAROUND_AMPERE_AC03_CPU_38))
- return true;
- return false;
-}
-static inline void __activate_traps_hfgxtr(void)
+static inline void __activate_traps_hfgxtr(struct kvm_vcpu *vcpu)
{
+ struct kvm_cpu_context *hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
u64 r_clr = 0, w_clr = 0, r_set = 0, w_set = 0, tmp;
+ u64 r_val, w_val;
+
+ if (!cpus_have_final_cap(ARM64_HAS_FGT))
+ return;
+
+ ctxt_sys_reg(hctxt, HFGRTR_EL2) = read_sysreg_s(SYS_HFGRTR_EL2);
+ ctxt_sys_reg(hctxt, HFGWTR_EL2) = read_sysreg_s(SYS_HFGWTR_EL2);
if (cpus_have_final_cap(ARM64_SME)) {
tmp = HFGxTR_EL2_nSMPRI_EL1_MASK | HFGxTR_EL2_nTPIDR2_EL0_MASK;
@@ -98,26 +97,31 @@ static inline void __activate_traps_hfgxtr(void)
if (cpus_have_final_cap(ARM64_WORKAROUND_AMPERE_AC03_CPU_38))
w_set |= HFGxTR_EL2_TCR_EL1_MASK;
- sysreg_clear_set_s(SYS_HFGRTR_EL2, r_clr, r_set);
- sysreg_clear_set_s(SYS_HFGWTR_EL2, w_clr, w_set);
+
+ /* The default is not to trap amything but ACCDATA_EL1 */
+ r_val = __HFGRTR_EL2_nMASK & ~HFGxTR_EL2_nACCDATA_EL1;
+ r_val |= r_set;
+ r_val &= ~r_clr;
+
+ w_val = __HFGWTR_EL2_nMASK & ~HFGxTR_EL2_nACCDATA_EL1;
+ w_val |= w_set;
+ w_val &= ~w_clr;
+
+ write_sysreg_s(r_val, SYS_HFGRTR_EL2);
+ write_sysreg_s(w_val, SYS_HFGWTR_EL2);
}
-static inline void __deactivate_traps_hfgxtr(void)
+static inline void __deactivate_traps_hfgxtr(struct kvm_vcpu *vcpu)
{
- u64 r_clr = 0, w_clr = 0, r_set = 0, w_set = 0, tmp;
+ struct kvm_cpu_context *hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
- if (cpus_have_final_cap(ARM64_SME)) {
- tmp = HFGxTR_EL2_nSMPRI_EL1_MASK | HFGxTR_EL2_nTPIDR2_EL0_MASK;
+ if (!cpus_have_final_cap(ARM64_HAS_FGT))
+ return;
- r_set |= tmp;
- w_set |= tmp;
- }
+ write_sysreg_s(ctxt_sys_reg(hctxt, HFGRTR_EL2), SYS_HFGRTR_EL2);
+ write_sysreg_s(ctxt_sys_reg(hctxt, HFGWTR_EL2), SYS_HFGWTR_EL2);
- if (cpus_have_final_cap(ARM64_WORKAROUND_AMPERE_AC03_CPU_38))
- w_clr |= HFGxTR_EL2_TCR_EL1_MASK;
- sysreg_clear_set_s(SYS_HFGRTR_EL2, r_clr, r_set);
- sysreg_clear_set_s(SYS_HFGWTR_EL2, w_clr, w_set);
}
static inline void __activate_traps_common(struct kvm_vcpu *vcpu)
@@ -145,8 +149,7 @@ static inline void __activate_traps_common(struct kvm_vcpu *vcpu)
vcpu->arch.mdcr_el2_host = read_sysreg(mdcr_el2);
write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
- if (__hfgxtr_traps_required())
- __activate_traps_hfgxtr();
+ __activate_traps_hfgxtr(vcpu);
}
static inline void __deactivate_traps_common(struct kvm_vcpu *vcpu)
@@ -162,8 +165,7 @@ static inline void __deactivate_traps_common(struct kvm_vcpu *vcpu)
vcpu_clear_flag(vcpu, PMUSERENR_ON_CPU);
}
- if (__hfgxtr_traps_required())
- __deactivate_traps_hfgxtr();
+ __deactivate_traps_hfgxtr(vcpu);
}
static inline void ___activate_traps(struct kvm_vcpu *vcpu)
--
2.34.1
