Add support for FEAT_DIT. DIT (Data Independent Timing) is a required
feature for ARMv8.4. Since virtual machine execution is largely
nondeterministic and TCG is outside of the security domain, it's
implemented as a NOP.
Signed-off-by: Rebecca Cran <rebecca@nuviainc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id:
20210208065700.19454-2-rebecca@nuviainc.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
#define CPSR_IT_2_7 (0xfc00U)
#define CPSR_GE (0xfU << 16)
#define CPSR_IL (1U << 20)
+#define CPSR_DIT (1U << 21)
#define CPSR_PAN (1U << 22)
#define CPSR_J (1U << 24)
#define CPSR_IT_0_1 (3U << 25)
#define PSTATE_SS (1U << 21)
#define PSTATE_PAN (1U << 22)
#define PSTATE_UAO (1U << 23)
+#define PSTATE_DIT (1U << 24)
#define PSTATE_TCO (1U << 25)
#define PSTATE_V (1U << 28)
#define PSTATE_C (1U << 29)
return FIELD_EX32(id->id_mmfr4, ID_MMFR4, XNX) != 0;
}
+static inline bool isar_feature_aa32_dit(const ARMISARegisters *id)
+{
+ return FIELD_EX32(id->id_pfr0, ID_PFR0, DIT) != 0;
+}
+
/*
* 64-bit feature tests via id registers.
*/
return FIELD_EX64(id->id_aa64mmfr1, ID_AA64MMFR1, XNX) != 0;
}
+static inline bool isar_feature_aa64_dit(const ARMISARegisters *id)
+{
+ return FIELD_EX64(id->id_aa64pfr0, ID_AA64PFR0, DIT) != 0;
+}
+
/*
* Feature tests for "does this exist in either 32-bit or 64-bit?"
*/
.readfn = aa64_uao_read, .writefn = aa64_uao_write
};
+static uint64_t aa64_dit_read(CPUARMState *env, const ARMCPRegInfo *ri)
+{
+ return env->pstate & PSTATE_DIT;
+}
+
+static void aa64_dit_write(CPUARMState *env, const ARMCPRegInfo *ri,
+ uint64_t value)
+{
+ env->pstate = (env->pstate & ~PSTATE_DIT) | (value & PSTATE_DIT);
+}
+
+static const ARMCPRegInfo dit_reginfo = {
+ .name = "DIT", .state = ARM_CP_STATE_AA64,
+ .opc0 = 3, .opc1 = 3, .crn = 4, .crm = 2, .opc2 = 5,
+ .type = ARM_CP_NO_RAW, .access = PL0_RW,
+ .readfn = aa64_dit_read, .writefn = aa64_dit_write
+};
+
static CPAccessResult aa64_cacheop_poc_access(CPUARMState *env,
const ARMCPRegInfo *ri,
bool isread)
define_one_arm_cp_reg(cpu, &uao_reginfo);
}
+ if (cpu_isar_feature(aa64_dit, cpu)) {
+ define_one_arm_cp_reg(cpu, &dit_reginfo);
+ }
+
if (arm_feature(env, ARM_FEATURE_EL2) && cpu_isar_feature(aa64_vh, cpu)) {
define_arm_cp_regs(cpu, vhe_reginfo);
}
if (isar_feature_aa32_pan(id)) {
valid |= CPSR_PAN;
}
+ if (isar_feature_aa32_dit(id)) {
+ valid |= CPSR_DIT;
+ }
return valid;
}
if (isar_feature_aa64_uao(id)) {
valid |= PSTATE_UAO;
}
+ if (isar_feature_aa64_dit(id)) {
+ valid |= PSTATE_DIT;
+ }
if (isar_feature_aa64_mte(id)) {
valid |= PSTATE_TCO;
}
tcg_temp_free_i32(t1);
break;
+ case 0x1a: /* DIT */
+ if (!dc_isar_feature(aa64_dit, s)) {
+ goto do_unallocated;
+ }
+ if (crm & 1) {
+ set_pstate_bits(PSTATE_DIT);
+ } else {
+ clear_pstate_bits(PSTATE_DIT);
+ }
+ /* There's no need to rebuild hflags because DIT is a nop */
+ break;
+
case 0x1e: /* DAIFSet */
t1 = tcg_const_i32(crm);
gen_helper_msr_i_daifset(cpu_env, t1);