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-rw-r--r--hw/arm/boot.c95
-rw-r--r--target/arm/arm-powerctl.c53
-rw-r--r--target/arm/cpu.c95
-rw-r--r--target/arm/cpu.h22
4 files changed, 141 insertions, 124 deletions
diff --git a/hw/arm/boot.c b/hw/arm/boot.c
index 24fa169060..84ea6a807a 100644
--- a/hw/arm/boot.c
+++ b/hw/arm/boot.c
@@ -722,84 +722,35 @@ static void do_cpu_reset(void *opaque)
 
             cpu_set_pc(cs, entry);
         } else {
-            /* If we are booting Linux then we need to check whether we are
-             * booting into secure or non-secure state and adjust the state
-             * accordingly.  Out of reset, ARM is defined to be in secure state
-             * (SCR.NS = 0), we change that here if non-secure boot has been
-             * requested.
+            /*
+             * If we are booting Linux then we might need to do so at:
+             *  - AArch64 NS EL2 or NS EL1
+             *  - AArch32 Secure SVC (EL3)
+             *  - AArch32 NS Hyp (EL2)
+             *  - AArch32 NS SVC (EL1)
+             * Configure the CPU in the way boot firmware would do to
+             * drop us down to the appropriate level.
              */
-            if (arm_feature(env, ARM_FEATURE_EL3)) {
-                /* AArch64 is defined to come out of reset into EL3 if enabled.
-                 * If we are booting Linux then we need to adjust our EL as
-                 * Linux expects us to be in EL2 or EL1.  AArch32 resets into
-                 * SVC, which Linux expects, so no privilege/exception level to
-                 * adjust.
-                 */
-                if (env->aarch64) {
-                    env->cp15.scr_el3 |= SCR_RW;
-                    if (arm_feature(env, ARM_FEATURE_EL2)) {
-                        env->cp15.hcr_el2 |= HCR_RW;
-                        env->pstate = PSTATE_MODE_EL2h;
-                    } else {
-                        env->pstate = PSTATE_MODE_EL1h;
-                    }
-                    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;
-                    }
+            int target_el = arm_feature(env, ARM_FEATURE_EL2) ? 2 : 1;
 
-                    /* AArch64 kernels never boot in secure mode */
-                    assert(!info->secure_boot);
-                    /* This hook is only supported for AArch32 currently:
-                     * bootloader_aarch64[] will not call the hook, and
-                     * the code above has already dropped us into EL2 or EL1.
-                     */
-                    assert(!info->secure_board_setup);
-                }
-
-                if (arm_feature(env, ARM_FEATURE_EL2)) {
-                    /* If we have EL2 then Linux expects the HVC insn to work */
-                    env->cp15.scr_el3 |= SCR_HCE;
-                }
-
-                /* Set to non-secure if not a secure boot */
-                if (!info->secure_boot &&
-                    (cs != first_cpu || !info->secure_board_setup)) {
-                    /* Linux expects 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 (!env->aarch64 && !info->secure_boot &&
-                arm_feature(env, ARM_FEATURE_EL2)) {
+            if (env->aarch64) {
                 /*
-                 * This is an AArch32 boot not to Secure state, and
-                 * we have Hyp mode available, so boot the kernel into
-                 * Hyp mode. This is not how the CPU comes out of reset,
-                 * so we need to manually put it there.
+                 * AArch64 kernels never boot in secure mode, and we don't
+                 * support the secure_board_setup hook for AArch64.
                  */
-                cpsr_write(env, ARM_CPU_MODE_HYP, CPSR_M, CPSRWriteRaw);
+                assert(!info->secure_boot);
+                assert(!info->secure_board_setup);
+            } else {
+                if (arm_feature(env, ARM_FEATURE_EL3) &&
+                    (info->secure_boot ||
+                     (info->secure_board_setup && cs == first_cpu))) {
+                    /* Start this CPU in Secure SVC */
+                    target_el = 3;
+                }
             }
 
+            arm_emulate_firmware_reset(cs, target_el);
+
             if (cs == first_cpu) {
                 AddressSpace *as = arm_boot_address_space(cpu, info);
 
diff --git a/target/arm/arm-powerctl.c b/target/arm/arm-powerctl.c
index 326a03153d..c078849403 100644
--- a/target/arm/arm-powerctl.c
+++ b/target/arm/arm-powerctl.c
@@ -65,60 +65,9 @@ static void arm_set_cpu_on_async_work(CPUState *target_cpu_state,
 
     /* Initialize the cpu we are turning on */
     cpu_reset(target_cpu_state);
+    arm_emulate_firmware_reset(target_cpu_state, info->target_el);
     target_cpu_state->halted = 0;
 
-    if (info->target_aa64) {
-        if ((info->target_el < 3) && arm_feature(&target_cpu->env,
-                                                 ARM_FEATURE_EL3)) {
-            /*
-             * As target mode is AArch64, we need to set lower
-             * exception level (the requested level 2) to AArch64
-             */
-            target_cpu->env.cp15.scr_el3 |= SCR_RW;
-        }
-
-        if ((info->target_el < 2) && arm_feature(&target_cpu->env,
-                                                 ARM_FEATURE_EL2)) {
-            /*
-             * As target mode is AArch64, we need to set lower
-             * exception level (the requested level 1) to AArch64
-             */
-            target_cpu->env.cp15.hcr_el2 |= HCR_RW;
-        }
-
-        target_cpu->env.pstate = aarch64_pstate_mode(info->target_el, true);
-    } else {
-        /* We are requested to boot in AArch32 mode */
-        static const uint32_t mode_for_el[] = { 0,
-                                                ARM_CPU_MODE_SVC,
-                                                ARM_CPU_MODE_HYP,
-                                                ARM_CPU_MODE_SVC };
-
-        cpsr_write(&target_cpu->env, mode_for_el[info->target_el], CPSR_M,
-                   CPSRWriteRaw);
-    }
-
-    if (info->target_el == 3) {
-        /* Processor is in secure mode */
-        target_cpu->env.cp15.scr_el3 &= ~SCR_NS;
-    } else {
-        /* Processor is not in secure mode */
-        target_cpu->env.cp15.scr_el3 |= SCR_NS;
-
-        /* Set NSACR.{CP11,CP10} so NS can access the FPU */
-        target_cpu->env.cp15.nsacr |= 3 << 10;
-
-        /*
-         * If QEMU is providing the equivalent of EL3 firmware, then we need
-         * to make sure a CPU targeting EL2 comes out of reset with a
-         * functional HVC insn.
-         */
-        if (arm_feature(&target_cpu->env, ARM_FEATURE_EL3)
-            && info->target_el == 2) {
-            target_cpu->env.cp15.scr_el3 |= SCR_HCE;
-        }
-    }
-
     /* We check if the started CPU is now at the correct level */
     assert(info->target_el == arm_current_el(&target_cpu->env));
 
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,
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index a9edfb8353..76d4cef9e3 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1149,6 +1149,28 @@ int arm_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
 int arm_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
                              int cpuid, DumpState *s);
 
+/**
+ * arm_emulate_firmware_reset: Emulate firmware CPU reset handling
+ * @cpu: CPU (which must have been freshly reset)
+ * @target_el: exception level to put the CPU into
+ * @secure: whether to put the CPU in secure state
+ *
+ * When QEMU is directly running a guest kernel at a lower level than
+ * EL3 it implicitly emulates some aspects of the guest firmware.
+ * This includes that on reset we need to configure the parts of the
+ * CPU corresponding to EL3 so that the real guest code can run at its
+ * lower exception level. This function does that post-reset CPU setup,
+ * for when we do direct boot of a guest kernel, and for when we
+ * emulate PSCI and similar firmware interfaces starting a CPU at a
+ * lower exception level.
+ *
+ * @target_el must be an EL implemented by the CPU between 1 and 3.
+ * We do not support dropping into a Secure EL other than 3.
+ *
+ * It is the responsibility of the caller to call arm_rebuild_hflags().
+ */
+void arm_emulate_firmware_reset(CPUState *cpustate, int target_el);
+
 #ifdef TARGET_AARCH64
 int aarch64_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
 int aarch64_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);