diff options
Diffstat (limited to 'target/arm/cpu.c')
| -rw-r--r-- | target/arm/cpu.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 6c6c551573..aa4e006f21 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -553,6 +553,101 @@ static void arm_cpu_reset_hold(Object *obj) } } +void arm_emulate_firmware_reset(CPUState *cpustate, int target_el) +{ + ARMCPU *cpu = ARM_CPU(cpustate); + CPUARMState *env = &cpu->env; + bool have_el3 = arm_feature(env, ARM_FEATURE_EL3); + bool have_el2 = arm_feature(env, ARM_FEATURE_EL2); + + /* + * Check we have the EL we're aiming for. If that is the + * highest implemented EL, then cpu_reset has already done + * all the work. + */ + switch (target_el) { + case 3: + assert(have_el3); + return; + case 2: + assert(have_el2); + if (!have_el3) { + return; + } + break; + case 1: + if (!have_el3 && !have_el2) { + return; + } + break; + default: + g_assert_not_reached(); + } + + if (have_el3) { + /* + * Set the EL3 state so code can run at EL2. This should match + * the requirements set by Linux in its booting spec. + */ + if (env->aarch64) { + env->cp15.scr_el3 |= SCR_RW; + if (cpu_isar_feature(aa64_pauth, cpu)) { + env->cp15.scr_el3 |= SCR_API | SCR_APK; + } + if (cpu_isar_feature(aa64_mte, cpu)) { + env->cp15.scr_el3 |= SCR_ATA; + } + if (cpu_isar_feature(aa64_sve, cpu)) { + env->cp15.cptr_el[3] |= R_CPTR_EL3_EZ_MASK; + env->vfp.zcr_el[3] = 0xf; + } + if (cpu_isar_feature(aa64_sme, cpu)) { + env->cp15.cptr_el[3] |= R_CPTR_EL3_ESM_MASK; + env->cp15.scr_el3 |= SCR_ENTP2; + env->vfp.smcr_el[3] = 0xf; + } + if (cpu_isar_feature(aa64_hcx, cpu)) { + env->cp15.scr_el3 |= SCR_HXEN; + } + if (cpu_isar_feature(aa64_fgt, cpu)) { + env->cp15.scr_el3 |= SCR_FGTEN; + } + } + + if (target_el == 2) { + /* If the guest is at EL2 then Linux expects the HVC insn to work */ + env->cp15.scr_el3 |= SCR_HCE; + } + + /* Put CPU into non-secure state */ + env->cp15.scr_el3 |= SCR_NS; + /* Set NSACR.{CP11,CP10} so NS can access the FPU */ + env->cp15.nsacr |= 3 << 10; + } + + if (have_el2 && target_el < 2) { + /* Set EL2 state so code can run at EL1. */ + if (env->aarch64) { + env->cp15.hcr_el2 |= HCR_RW; + } + } + + /* Set the CPU to the desired state */ + if (env->aarch64) { + env->pstate = aarch64_pstate_mode(target_el, true); + } else { + static const uint32_t mode_for_el[] = { + 0, + ARM_CPU_MODE_SVC, + ARM_CPU_MODE_HYP, + ARM_CPU_MODE_SVC, + }; + + cpsr_write(env, mode_for_el[target_el], CPSR_M, CPSRWriteRaw); + } +} + + #if defined(CONFIG_TCG) && !defined(CONFIG_USER_ONLY) static inline bool arm_excp_unmasked(CPUState *cs, unsigned int excp_idx, |