Add FEAT_SCTLR2, which introduces the SCTLR2_EL1, SCTLR2_EL2, and
SCTLR2_EL3 registers. These registers are extensions of the SCTLR_ELx
ones.
Because the bits in these registers depend on other CPU features, and
only FEAT_MEC is supported at the moment, this commit only implements
the EMEC bits in CTLR2_EL2 and SCTLR2_EL3.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
---
docs/system/arm/emulation.rst | 1 +
target/arm/cpu-features.h | 5 +++
target/arm/cpu.h | 15 +++++++
target/arm/helper.c | 78 +++++++++++++++++++++++++++++++++++
target/arm/internals.h | 1 +
target/arm/tcg/cpu64.c | 1 +
6 files changed, 101 insertions(+)
diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst
index 890dc6fee2..66043b0747 100644
--- a/docs/system/arm/emulation.rst
+++ b/docs/system/arm/emulation.rst
@@ -121,6 +121,7 @@ the following architecture extensions:
- FEAT_RPRES (Increased precision of FRECPE and FRSQRTE)
- FEAT_S2FWB (Stage 2 forced Write-Back)
- FEAT_SB (Speculation Barrier)
+- FEAT_SCTLR2 (Extension to SCTLR_ELx)
- FEAT_SEL2 (Secure EL2)
- FEAT_SHA1 (SHA1 instructions)
- FEAT_SHA256 (SHA256 instructions)
diff --git a/target/arm/cpu-features.h b/target/arm/cpu-features.h
index 552d8757b7..44d6b655a9 100644
--- a/target/arm/cpu-features.h
+++ b/target/arm/cpu-features.h
@@ -416,6 +416,11 @@ static inline bool isar_feature_aa64_rdm(const ARMISARegisters *id)
return FIELD_EX64_IDREG(id, ID_AA64ISAR0, RDM) != 0;
}
+static inline bool isar_feature_aa64_sctlr2(const ARMISARegisters *id)
+{
+ return FIELD_EX64_IDREG(id, ID_AA64MMFR3, SCTLRX) != 0;
+}
+
static inline bool isar_feature_aa64_sha3(const ARMISARegisters *id)
{
return FIELD_EX64_IDREG(id, ID_AA64ISAR0, SHA3) != 0;
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index a93eebe077..32d30b7bb9 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -337,6 +337,7 @@ typedef struct CPUArchState {
};
uint64_t sctlr_el[4];
};
+ uint64_t sctlr2_el[4]; /* Extension to System control register. */
uint64_t vsctlr; /* Virtualization System control register. */
uint64_t cpacr_el1; /* Architectural feature access control register */
uint64_t cptr_el[4]; /* ARMv8 feature trap registers */
@@ -1433,6 +1434,19 @@ void pmu_init(ARMCPU *cpu);
#define SCTLR_SPINTMASK (1ULL << 62) /* FEAT_NMI */
#define SCTLR_TIDCP (1ULL << 63) /* FEAT_TIDCP1 */
+#define SCTLR2_EMEC (1ULL << 1) /* FEAT_MEC */
+#define SCTLR2_NMEA (1ULL << 2) /* FEAT_DoubleFault2 */
+#define SCTLR2_ENADERR (1ULL << 3) /* FEAT_ADERR */
+#define SCTLR2_ENANERR (1ULL << 4) /* FEAT_ANERR */
+#define SCTLR2_EASE (1ULL << 5) /* FEAT_DoubleFault2 */
+#define SCTLR2_ENIDCP128 (1ULL << 6) /* FEAT_SYSREG128 */
+#define SCTLR2_ENPACM (1ULL << 7) /* FEAT_PAuth_LR */
+#define SCTLR2_ENPACM0 (1ULL << 8 /* FEAT_PAuth_LR */
+#define SCTLR2_CPTA (1ULL << 9) /* FEAT_CPA2 */
+#define SCTLR2_CPTA0 (1ULL << 10) /* FEAT_CPA2 */
+#define SCTLR2_CPTM (1ULL << 11) /* FEAT_CPA2 */
+#define SCTLR2_CPTM0 (1ULL << 12) /* FEAT_CAP2 */
+
#define CPSR_M (0x1fU)
#define CPSR_T (1U << 5)
#define CPSR_F (1U << 6)
@@ -1725,6 +1739,7 @@ static inline void xpsr_write(CPUARMState *env, uint32_t val, uint32_t mask)
#define SCR_HXEN (1ULL << 38)
#define SCR_TRNDR (1ULL << 40)
#define SCR_ENTP2 (1ULL << 41)
+#define SCR_SCTLR2EN (1ULL << 44)
#define SCR_GPF (1ULL << 48)
#define SCR_MECEN (1ULL << 49)
#define SCR_NSE (1ULL << 62)
diff --git a/target/arm/helper.c b/target/arm/helper.c
index 984406c945..5707eea822 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -6144,6 +6144,8 @@ static void define_arm_vh_e2h_redirects_aliases(ARMCPU *cpu)
static const struct E2HAlias aliases[] = {
{ K(3, 0, 1, 0, 0), K(3, 4, 1, 0, 0), K(3, 5, 1, 0, 0),
"SCTLR", "SCTLR_EL2", "SCTLR_EL12" },
+ { K(3, 0, 1, 0, 3), K(3, 4, 1, 0, 3), K(3, 5, 1, 0, 3),
+ "SCTLR2_EL1", "SCTLR2_EL2", "SCTLR2_EL12" },
{ K(3, 0, 1, 0, 2), K(3, 4, 1, 1, 2), K(3, 5, 1, 0, 2),
"CPACR", "CPTR_EL2", "CPACR_EL12" },
{ K(3, 0, 2, 0, 0), K(3, 4, 2, 0, 0), K(3, 5, 2, 0, 0),
@@ -7816,6 +7818,78 @@ static const ARMCPRegInfo actlr2_hactlr2_reginfo[] = {
.resetvalue = 0 },
};
+static CPAccessResult sctlr2_el2_access(CPUARMState *env,
+ const ARMCPRegInfo *ri,
+ bool isread)
+{
+ if (arm_current_el(env) < 3 && !(env->cp15.scr_el3 & SCR_SCTLR2EN)) {
+ return CP_ACCESS_TRAP_EL3;
+ }
+ return CP_ACCESS_OK;
+};
+
+static CPAccessResult sctlr2_el1_access(CPUARMState *env,
+ const ARMCPRegInfo *ri,
+ bool isread)
+{
+ CPAccessResult ret = access_tvm_trvm(env, ri, isread);
+ if (ret != CP_ACCESS_OK) {
+ return ret;
+ }
+ if (arm_current_el(env) < 2 && !(arm_hcrx_el2_eff(env) & HCRX_SCTLR2EN)) {
+ return CP_ACCESS_TRAP_EL2;
+ }
+ return sctlr2_el2_access(env, ri, isread);
+};
+
+static void sctlr2_el1_write(CPUARMState *env, const ARMCPRegInfo *ri,
+ uint64_t value)
+{
+ /* This register does not control any feature yet. */
+};
+
+static void sctlr2_el2_write(CPUARMState *env, const ARMCPRegInfo *ri,
+ uint64_t value)
+{
+ uint64_t valid_mask = 0;
+
+ if (cpu_isar_feature(aa64_mec, env_archcpu(env))) {
+ valid_mask |= SCTLR2_EMEC;
+ }
+ value &= valid_mask;
+ raw_write(env, ri, value);
+};
+
+static void sctlr2_el3_write(CPUARMState *env, const ARMCPRegInfo *ri,
+ uint64_t value)
+{
+ uint64_t valid_mask = 0;
+
+ if (cpu_isar_feature(aa64_mec, env_archcpu(env))) {
+ valid_mask |= SCTLR2_EMEC;
+ }
+ value &= valid_mask;
+ raw_write(env, ri, value);
+};
+
+static const ARMCPRegInfo sctlr2_reginfo[] = {
+ { .name = "SCTLR2_EL1", .state = ARM_CP_STATE_AA64,
+ .opc0 = 3, .opc1 = 0, .opc2 = 3, .crn = 1, .crm = 0,
+ .access = PL1_RW, .accessfn = sctlr2_el1_access,
+ .writefn = sctlr2_el1_write, .fgt = FGT_SCTLR_EL1,
+ .nv2_redirect_offset = 0x278 | NV2_REDIR_NV1,
+ .fieldoffset = offsetof(CPUARMState, cp15.sctlr2_el[1]) },
+ { .name = "SCTLR2_EL2", .state = ARM_CP_STATE_AA64,
+ .opc0 = 3, .opc1 = 4, .opc2 = 3, .crn = 1, .crm = 0,
+ .access = PL2_RW, .accessfn = sctlr2_el2_access,
+ .writefn = sctlr2_el2_write,
+ .fieldoffset = offsetof(CPUARMState, cp15.sctlr2_el[2]) },
+ { .name = "SCTLR2_EL3", .state = ARM_CP_STATE_AA64,
+ .opc0 = 3, .opc1 = 6, .opc2 = 3, .crn = 1, .crm = 0,
+ .access = PL3_RW, .writefn = sctlr2_el3_write,
+ .fieldoffset = offsetof(CPUARMState, cp15.sctlr2_el[3]) },
+};
+
void register_cp_regs_for_features(ARMCPU *cpu)
{
/* Register all the coprocessor registers based on feature bits */
@@ -9084,6 +9158,10 @@ void register_cp_regs_for_features(ARMCPU *cpu)
define_arm_cp_regs(cpu, mec_reginfo);
}
+ if (cpu_isar_feature(aa64_sctlr2, cpu)) {
+ define_arm_cp_regs(cpu, sctlr2_reginfo);
+ }
+
if (cpu_isar_feature(any_predinv, cpu)) {
define_arm_cp_regs(cpu, predinv_reginfo);
}
diff --git a/target/arm/internals.h b/target/arm/internals.h
index 21a8d67edd..398e0b4a7d 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -232,6 +232,7 @@ FIELD(VTCR, SL2, 33, 1)
#define HCRX_CMOW (1ULL << 9)
#define HCRX_MCE2 (1ULL << 10)
#define HCRX_MSCEN (1ULL << 11)
+#define HCRX_SCTLR2EN (1ULL << 15)
#define HPFAR_NS (1ULL << 63)
diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
index d0df50a2f3..bdd2fe7f5b 100644
--- a/target/arm/tcg/cpu64.c
+++ b/target/arm/tcg/cpu64.c
@@ -1247,6 +1247,7 @@ void aarch64_max_tcg_initfn(Object *obj)
t = FIELD_DP64(t, ID_AA64MMFR2, E0PD, 1); /* FEAT_E0PD */
SET_IDREG(isar, ID_AA64MMFR2, t);
+ FIELD_DP64_IDREG(isar, ID_AA64MMFR3, SCTLRX, 1); /* FEAT_SCTLR2 */
FIELD_DP64_IDREG(isar, ID_AA64MMFR3, SPEC_FPACC, 1); /* FEAT_FPACC_SPEC */
t = GET_IDREG(isar, ID_AA64ZFR0);
--
2.34.1On 7/8/25 13:17, Gustavo Romero wrote:
> Add FEAT_SCTLR2, which introduces the SCTLR2_EL1, SCTLR2_EL2, and
> SCTLR2_EL3 registers. These registers are extensions of the SCTLR_ELx
> ones.
>
> Because the bits in these registers depend on other CPU features, and
> only FEAT_MEC is supported at the moment, this commit only implements
> the EMEC bits in CTLR2_EL2 and SCTLR2_EL3.
>
> Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
> ---
> docs/system/arm/emulation.rst | 1 +
> target/arm/cpu-features.h | 5 +++
> target/arm/cpu.h | 15 +++++++
> target/arm/helper.c | 78 +++++++++++++++++++++++++++++++++++
> target/arm/internals.h | 1 +
> target/arm/tcg/cpu64.c | 1 +
> 6 files changed, 101 insertions(+)
>
> diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst
> index 890dc6fee2..66043b0747 100644
> --- a/docs/system/arm/emulation.rst
> +++ b/docs/system/arm/emulation.rst
> @@ -121,6 +121,7 @@ the following architecture extensions:
> - FEAT_RPRES (Increased precision of FRECPE and FRSQRTE)
> - FEAT_S2FWB (Stage 2 forced Write-Back)
> - FEAT_SB (Speculation Barrier)
> +- FEAT_SCTLR2 (Extension to SCTLR_ELx)
> - FEAT_SEL2 (Secure EL2)
> - FEAT_SHA1 (SHA1 instructions)
> - FEAT_SHA256 (SHA256 instructions)
> diff --git a/target/arm/cpu-features.h b/target/arm/cpu-features.h
> index 552d8757b7..44d6b655a9 100644
> --- a/target/arm/cpu-features.h
> +++ b/target/arm/cpu-features.h
> @@ -416,6 +416,11 @@ static inline bool isar_feature_aa64_rdm(const ARMISARegisters *id)
> return FIELD_EX64_IDREG(id, ID_AA64ISAR0, RDM) != 0;
> }
>
> +static inline bool isar_feature_aa64_sctlr2(const ARMISARegisters *id)
> +{
> + return FIELD_EX64_IDREG(id, ID_AA64MMFR3, SCTLRX) != 0;
> +}
> +
> static inline bool isar_feature_aa64_sha3(const ARMISARegisters *id)
> {
> return FIELD_EX64_IDREG(id, ID_AA64ISAR0, SHA3) != 0;
> diff --git a/target/arm/cpu.h b/target/arm/cpu.h
> index a93eebe077..32d30b7bb9 100644
> --- a/target/arm/cpu.h
> +++ b/target/arm/cpu.h
> @@ -337,6 +337,7 @@ typedef struct CPUArchState {
> };
> uint64_t sctlr_el[4];
> };
> + uint64_t sctlr2_el[4]; /* Extension to System control register. */
> uint64_t vsctlr; /* Virtualization System control register. */
> uint64_t cpacr_el1; /* Architectural feature access control register */
> uint64_t cptr_el[4]; /* ARMv8 feature trap registers */
> @@ -1433,6 +1434,19 @@ void pmu_init(ARMCPU *cpu);
> #define SCTLR_SPINTMASK (1ULL << 62) /* FEAT_NMI */
> #define SCTLR_TIDCP (1ULL << 63) /* FEAT_TIDCP1 */
>
> +#define SCTLR2_EMEC (1ULL << 1) /* FEAT_MEC */
> +#define SCTLR2_NMEA (1ULL << 2) /* FEAT_DoubleFault2 */
> +#define SCTLR2_ENADERR (1ULL << 3) /* FEAT_ADERR */
> +#define SCTLR2_ENANERR (1ULL << 4) /* FEAT_ANERR */
> +#define SCTLR2_EASE (1ULL << 5) /* FEAT_DoubleFault2 */
> +#define SCTLR2_ENIDCP128 (1ULL << 6) /* FEAT_SYSREG128 */
> +#define SCTLR2_ENPACM (1ULL << 7) /* FEAT_PAuth_LR */
> +#define SCTLR2_ENPACM0 (1ULL << 8 /* FEAT_PAuth_LR */
> +#define SCTLR2_CPTA (1ULL << 9) /* FEAT_CPA2 */
> +#define SCTLR2_CPTA0 (1ULL << 10) /* FEAT_CPA2 */
> +#define SCTLR2_CPTM (1ULL << 11) /* FEAT_CPA2 */
> +#define SCTLR2_CPTM0 (1ULL << 12) /* FEAT_CAP2 */
> +
> #define CPSR_M (0x1fU)
> #define CPSR_T (1U << 5)
> #define CPSR_F (1U << 6)
> @@ -1725,6 +1739,7 @@ static inline void xpsr_write(CPUARMState *env, uint32_t val, uint32_t mask)
> #define SCR_HXEN (1ULL << 38)
> #define SCR_TRNDR (1ULL << 40)
> #define SCR_ENTP2 (1ULL << 41)
> +#define SCR_SCTLR2EN (1ULL << 44)
> #define SCR_GPF (1ULL << 48)
> #define SCR_MECEN (1ULL << 49)
> #define SCR_NSE (1ULL << 62)
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 984406c945..5707eea822 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -6144,6 +6144,8 @@ static void define_arm_vh_e2h_redirects_aliases(ARMCPU *cpu)
> static const struct E2HAlias aliases[] = {
> { K(3, 0, 1, 0, 0), K(3, 4, 1, 0, 0), K(3, 5, 1, 0, 0),
> "SCTLR", "SCTLR_EL2", "SCTLR_EL12" },
> + { K(3, 0, 1, 0, 3), K(3, 4, 1, 0, 3), K(3, 5, 1, 0, 3),
> + "SCTLR2_EL1", "SCTLR2_EL2", "SCTLR2_EL12" },
> { K(3, 0, 1, 0, 2), K(3, 4, 1, 1, 2), K(3, 5, 1, 0, 2),
> "CPACR", "CPTR_EL2", "CPACR_EL12" },
> { K(3, 0, 2, 0, 0), K(3, 4, 2, 0, 0), K(3, 5, 2, 0, 0),
> @@ -7816,6 +7818,78 @@ static const ARMCPRegInfo actlr2_hactlr2_reginfo[] = {
> .resetvalue = 0 },
> };
>
> +static CPAccessResult sctlr2_el2_access(CPUARMState *env,
> + const ARMCPRegInfo *ri,
> + bool isread)
> +{
> + if (arm_current_el(env) < 3 && !(env->cp15.scr_el3 & SCR_SCTLR2EN)) {
> + return CP_ACCESS_TRAP_EL3;
> + }
Missing a check for arm_feature(env, ARM_FEATURE_EL3).
> + return CP_ACCESS_OK;
> +};
Stray ;
> +
> +static CPAccessResult sctlr2_el1_access(CPUARMState *env,
> + const ARMCPRegInfo *ri,
> + bool isread)
> +{
> + CPAccessResult ret = access_tvm_trvm(env, ri, isread);
> + if (ret != CP_ACCESS_OK) {
> + return ret;
> + }
> + if (arm_current_el(env) < 2 && !(arm_hcrx_el2_eff(env) & HCRX_SCTLR2EN)) {
> + return CP_ACCESS_TRAP_EL2;
> + }
> + return sctlr2_el2_access(env, ri, isread);
> +};
Stray ;
> +
> +static void sctlr2_el1_write(CPUARMState *env, const ARMCPRegInfo *ri,
> + uint64_t value)
> +{
> + /* This register does not control any feature yet. */
> +};
Stray ;
> +
> +static void sctlr2_el2_write(CPUARMState *env, const ARMCPRegInfo *ri,
> + uint64_t value)
> +{
> + uint64_t valid_mask = 0;
> +
> + if (cpu_isar_feature(aa64_mec, env_archcpu(env))) {
> + valid_mask |= SCTLR2_EMEC;
> + }
> + value &= valid_mask;
> + raw_write(env, ri, value);
> +};
Stray ;
> +
> +static void sctlr2_el3_write(CPUARMState *env, const ARMCPRegInfo *ri,
> + uint64_t value)
> +{
> + uint64_t valid_mask = 0;
> +
> + if (cpu_isar_feature(aa64_mec, env_archcpu(env))) {
> + valid_mask |= SCTLR2_EMEC;
> + }
> + value &= valid_mask;
> + raw_write(env, ri, value);
> +};
Stray ;
Otherwise,
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
r~
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