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-rw-r--r--hw/intc/armv7m_nvic.c261
1 files changed, 261 insertions, 0 deletions
diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c
index ab822f4251..fff6e694e6 100644
--- a/hw/intc/armv7m_nvic.c
+++ b/hw/intc/armv7m_nvic.c
@@ -655,6 +655,102 @@ void armv7m_nvic_set_pending_derived(void *opaque, int irq, bool secure)
     do_armv7m_nvic_set_pending(opaque, irq, secure, true);
 }
 
+void armv7m_nvic_set_pending_lazyfp(void *opaque, int irq, bool secure)
+{
+    /*
+     * Pend an exception during lazy FP stacking. This differs
+     * from the usual exception pending because the logic for
+     * whether we should escalate depends on the saved context
+     * in the FPCCR register, not on the current state of the CPU/NVIC.
+     */
+    NVICState *s = (NVICState *)opaque;
+    bool banked = exc_is_banked(irq);
+    VecInfo *vec;
+    bool targets_secure;
+    bool escalate = false;
+    /*
+     * We will only look at bits in fpccr if this is a banked exception
+     * (in which case 'secure' tells us whether it is the S or NS version).
+     * All the bits for the non-banked exceptions are in fpccr_s.
+     */
+    uint32_t fpccr_s = s->cpu->env.v7m.fpccr[M_REG_S];
+    uint32_t fpccr = s->cpu->env.v7m.fpccr[secure];
+
+    assert(irq > ARMV7M_EXCP_RESET && irq < s->num_irq);
+    assert(!secure || banked);
+
+    vec = (banked && secure) ? &s->sec_vectors[irq] : &s->vectors[irq];
+
+    targets_secure = banked ? secure : exc_targets_secure(s, irq);
+
+    switch (irq) {
+    case ARMV7M_EXCP_DEBUG:
+        if (!(fpccr_s & R_V7M_FPCCR_MONRDY_MASK)) {
+            /* Ignore DebugMonitor exception */
+            return;
+        }
+        break;
+    case ARMV7M_EXCP_MEM:
+        escalate = !(fpccr & R_V7M_FPCCR_MMRDY_MASK);
+        break;
+    case ARMV7M_EXCP_USAGE:
+        escalate = !(fpccr & R_V7M_FPCCR_UFRDY_MASK);
+        break;
+    case ARMV7M_EXCP_BUS:
+        escalate = !(fpccr_s & R_V7M_FPCCR_BFRDY_MASK);
+        break;
+    case ARMV7M_EXCP_SECURE:
+        escalate = !(fpccr_s & R_V7M_FPCCR_SFRDY_MASK);
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    if (escalate) {
+        /*
+         * Escalate to HardFault: faults that initially targeted Secure
+         * continue to do so, even if HF normally targets NonSecure.
+         */
+        irq = ARMV7M_EXCP_HARD;
+        if (arm_feature(&s->cpu->env, ARM_FEATURE_M_SECURITY) &&
+            (targets_secure ||
+             !(s->cpu->env.v7m.aircr & R_V7M_AIRCR_BFHFNMINS_MASK))) {
+            vec = &s->sec_vectors[irq];
+        } else {
+            vec = &s->vectors[irq];
+        }
+    }
+
+    if (!vec->enabled ||
+        nvic_exec_prio(s) <= exc_group_prio(s, vec->prio, secure)) {
+        if (!(fpccr_s & R_V7M_FPCCR_HFRDY_MASK)) {
+            /*
+             * We want to escalate to HardFault but the context the
+             * FP state belongs to prevents the exception pre-empting.
+             */
+            cpu_abort(&s->cpu->parent_obj,
+                      "Lockup: can't escalate to HardFault during "
+                      "lazy FP register stacking\n");
+        }
+    }
+
+    if (escalate) {
+        s->cpu->env.v7m.hfsr |= R_V7M_HFSR_FORCED_MASK;
+    }
+    if (!vec->pending) {
+        vec->pending = 1;
+        /*
+         * We do not call nvic_irq_update(), because we know our caller
+         * is going to handle causing us to take the exception by
+         * raising EXCP_LAZYFP, so raising the IRQ line would be
+         * pointless extra work. We just need to recompute the
+         * priorities so that armv7m_nvic_can_take_pending_exception()
+         * returns the right answer.
+         */
+        nvic_recompute_state(s);
+    }
+}
+
 /* Make pending IRQ active.  */
 void armv7m_nvic_acknowledge_irq(void *opaque)
 {
@@ -746,6 +842,40 @@ int armv7m_nvic_complete_irq(void *opaque, int irq, bool secure)
     return ret;
 }
 
+bool armv7m_nvic_get_ready_status(void *opaque, int irq, bool secure)
+{
+    /*
+     * Return whether an exception is "ready", i.e. it is enabled and is
+     * configured at a priority which would allow it to interrupt the
+     * current execution priority.
+     *
+     * irq and secure have the same semantics as for armv7m_nvic_set_pending():
+     * for non-banked exceptions secure is always false; for banked exceptions
+     * it indicates which of the exceptions is required.
+     */
+    NVICState *s = (NVICState *)opaque;
+    bool banked = exc_is_banked(irq);
+    VecInfo *vec;
+    int running = nvic_exec_prio(s);
+
+    assert(irq > ARMV7M_EXCP_RESET && irq < s->num_irq);
+    assert(!secure || banked);
+
+    /*
+     * HardFault is an odd special case: we always check against -1,
+     * even if we're secure and HardFault has priority -3; we never
+     * need to check for enabled state.
+     */
+    if (irq == ARMV7M_EXCP_HARD) {
+        return running > -1;
+    }
+
+    vec = (banked && secure) ? &s->sec_vectors[irq] : &s->vectors[irq];
+
+    return vec->enabled &&
+        exc_group_prio(s, vec->prio, secure) < running;
+}
+
 /* callback when external interrupt line is changed */
 static void set_irq_level(void *opaque, int n, int level)
 {
@@ -1077,6 +1207,16 @@ static uint32_t nvic_readl(NVICState *s, uint32_t offset, MemTxAttrs attrs)
     }
     case 0xd84: /* CSSELR */
         return cpu->env.v7m.csselr[attrs.secure];
+    case 0xd88: /* CPACR */
+        if (!arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            return 0;
+        }
+        return cpu->env.v7m.cpacr[attrs.secure];
+    case 0xd8c: /* NSACR */
+        if (!attrs.secure || !arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            return 0;
+        }
+        return cpu->env.v7m.nsacr;
     /* TODO: Implement debug registers.  */
     case 0xd90: /* MPU_TYPE */
         /* Unified MPU; if the MPU is not present this value is zero */
@@ -1222,6 +1362,49 @@ static uint32_t nvic_readl(NVICState *s, uint32_t offset, MemTxAttrs attrs)
             return 0;
         }
         return cpu->env.v7m.sfar;
+    case 0xf34: /* FPCCR */
+        if (!arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            return 0;
+        }
+        if (attrs.secure) {
+            return cpu->env.v7m.fpccr[M_REG_S];
+        } else {
+            /*
+             * NS can read LSPEN, CLRONRET and MONRDY. It can read
+             * BFRDY and HFRDY if AIRCR.BFHFNMINS != 0;
+             * other non-banked bits RAZ.
+             * TODO: MONRDY should RAZ/WI if DEMCR.SDME is set.
+             */
+            uint32_t value = cpu->env.v7m.fpccr[M_REG_S];
+            uint32_t mask = R_V7M_FPCCR_LSPEN_MASK |
+                R_V7M_FPCCR_CLRONRET_MASK |
+                R_V7M_FPCCR_MONRDY_MASK;
+
+            if (s->cpu->env.v7m.aircr & R_V7M_AIRCR_BFHFNMINS_MASK) {
+                mask |= R_V7M_FPCCR_BFRDY_MASK | R_V7M_FPCCR_HFRDY_MASK;
+            }
+
+            value &= mask;
+
+            value |= cpu->env.v7m.fpccr[M_REG_NS];
+            return value;
+        }
+    case 0xf38: /* FPCAR */
+        if (!arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            return 0;
+        }
+        return cpu->env.v7m.fpcar[attrs.secure];
+    case 0xf3c: /* FPDSCR */
+        if (!arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            return 0;
+        }
+        return cpu->env.v7m.fpdscr[attrs.secure];
+    case 0xf40: /* MVFR0 */
+        return cpu->isar.mvfr0;
+    case 0xf44: /* MVFR1 */
+        return cpu->isar.mvfr1;
+    case 0xf48: /* MVFR2 */
+        return cpu->isar.mvfr2;
     default:
     bad_offset:
         qemu_log_mask(LOG_GUEST_ERROR, "NVIC: Bad read offset 0x%x\n", offset);
@@ -1469,6 +1652,18 @@ static void nvic_writel(NVICState *s, uint32_t offset, uint32_t value,
             cpu->env.v7m.csselr[attrs.secure] = value & R_V7M_CSSELR_INDEX_MASK;
         }
         break;
+    case 0xd88: /* CPACR */
+        if (arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            /* We implement only the Floating Point extension's CP10/CP11 */
+            cpu->env.v7m.cpacr[attrs.secure] = value & (0xf << 20);
+        }
+        break;
+    case 0xd8c: /* NSACR */
+        if (attrs.secure && arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            /* We implement only the Floating Point extension's CP10/CP11 */
+            cpu->env.v7m.nsacr = value & (3 << 10);
+        }
+        break;
     case 0xd90: /* MPU_TYPE */
         return; /* RO */
     case 0xd94: /* MPU_CTRL */
@@ -1697,6 +1892,72 @@ static void nvic_writel(NVICState *s, uint32_t offset, uint32_t value,
         }
         break;
     }
+    case 0xf34: /* FPCCR */
+        if (arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            /* Not all bits here are banked. */
+            uint32_t fpccr_s;
+
+            if (!arm_feature(&cpu->env, ARM_FEATURE_V8)) {
+                /* Don't allow setting of bits not present in v7M */
+                value &= (R_V7M_FPCCR_LSPACT_MASK |
+                          R_V7M_FPCCR_USER_MASK |
+                          R_V7M_FPCCR_THREAD_MASK |
+                          R_V7M_FPCCR_HFRDY_MASK |
+                          R_V7M_FPCCR_MMRDY_MASK |
+                          R_V7M_FPCCR_BFRDY_MASK |
+                          R_V7M_FPCCR_MONRDY_MASK |
+                          R_V7M_FPCCR_LSPEN_MASK |
+                          R_V7M_FPCCR_ASPEN_MASK);
+            }
+            value &= ~R_V7M_FPCCR_RES0_MASK;
+
+            if (!attrs.secure) {
+                /* Some non-banked bits are configurably writable by NS */
+                fpccr_s = cpu->env.v7m.fpccr[M_REG_S];
+                if (!(fpccr_s & R_V7M_FPCCR_LSPENS_MASK)) {
+                    uint32_t lspen = FIELD_EX32(value, V7M_FPCCR, LSPEN);
+                    fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, LSPEN, lspen);
+                }
+                if (!(fpccr_s & R_V7M_FPCCR_CLRONRETS_MASK)) {
+                    uint32_t cor = FIELD_EX32(value, V7M_FPCCR, CLRONRET);
+                    fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, CLRONRET, cor);
+                }
+                if ((s->cpu->env.v7m.aircr & R_V7M_AIRCR_BFHFNMINS_MASK)) {
+                    uint32_t hfrdy = FIELD_EX32(value, V7M_FPCCR, HFRDY);
+                    uint32_t bfrdy = FIELD_EX32(value, V7M_FPCCR, BFRDY);
+                    fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, HFRDY, hfrdy);
+                    fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, BFRDY, bfrdy);
+                }
+                /* TODO MONRDY should RAZ/WI if DEMCR.SDME is set */
+                {
+                    uint32_t monrdy = FIELD_EX32(value, V7M_FPCCR, MONRDY);
+                    fpccr_s = FIELD_DP32(fpccr_s, V7M_FPCCR, MONRDY, monrdy);
+                }
+
+                /*
+                 * All other non-banked bits are RAZ/WI from NS; write
+                 * just the banked bits to fpccr[M_REG_NS].
+                 */
+                value &= R_V7M_FPCCR_BANKED_MASK;
+                cpu->env.v7m.fpccr[M_REG_NS] = value;
+            } else {
+                fpccr_s = value;
+            }
+            cpu->env.v7m.fpccr[M_REG_S] = fpccr_s;
+        }
+        break;
+    case 0xf38: /* FPCAR */
+        if (arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            value &= ~7;
+            cpu->env.v7m.fpcar[attrs.secure] = value;
+        }
+        break;
+    case 0xf3c: /* FPDSCR */
+        if (arm_feature(&cpu->env, ARM_FEATURE_VFP)) {
+            value &= 0x07c00000;
+            cpu->env.v7m.fpdscr[attrs.secure] = value;
+        }
+        break;
     case 0xf50: /* ICIALLU */
     case 0xf58: /* ICIMVAU */
     case 0xf5c: /* DCIMVAC */