| /* | 
 |  * ARM Generic Interrupt Controller v3 (emulation) | 
 |  * | 
 |  * Copyright (c) 2015 Huawei. | 
 |  * Copyright (c) 2016 Linaro Limited | 
 |  * Written by Shlomo Pongratz, Peter Maydell | 
 |  * | 
 |  * This code is licensed under the GPL, version 2 or (at your option) | 
 |  * any later version. | 
 |  */ | 
 |  | 
 | /* This file contains implementation code for an interrupt controller | 
 |  * which implements the GICv3 architecture. Specifically this is where | 
 |  * the device class itself and the functions for handling interrupts | 
 |  * coming in and going out live. | 
 |  */ | 
 |  | 
 | #include "qemu/osdep.h" | 
 | #include "qapi/error.h" | 
 | #include "qemu/module.h" | 
 | #include "hw/intc/arm_gicv3.h" | 
 | #include "gicv3_internal.h" | 
 |  | 
 | static bool irqbetter(GICv3CPUState *cs, int irq, uint8_t prio) | 
 | { | 
 |     /* Return true if this IRQ at this priority should take | 
 |      * precedence over the current recorded highest priority | 
 |      * pending interrupt for this CPU. We also return true if | 
 |      * the current recorded highest priority pending interrupt | 
 |      * is the same as this one (a property which the calling code | 
 |      * relies on). | 
 |      */ | 
 |     if (prio < cs->hppi.prio) { | 
 |         return true; | 
 |     } | 
 |     /* If multiple pending interrupts have the same priority then it is an | 
 |      * IMPDEF choice which of them to signal to the CPU. We choose to | 
 |      * signal the one with the lowest interrupt number. | 
 |      */ | 
 |     if (prio == cs->hppi.prio && irq <= cs->hppi.irq) { | 
 |         return true; | 
 |     } | 
 |     return false; | 
 | } | 
 |  | 
 | static uint32_t gicd_int_pending(GICv3State *s, int irq) | 
 | { | 
 |     /* Recalculate which distributor interrupts are actually pending | 
 |      * in the group of 32 interrupts starting at irq (which should be a multiple | 
 |      * of 32), and return a 32-bit integer which has a bit set for each | 
 |      * interrupt that is eligible to be signaled to the CPU interface. | 
 |      * | 
 |      * An interrupt is pending if: | 
 |      *  + the PENDING latch is set OR it is level triggered and the input is 1 | 
 |      *  + its ENABLE bit is set | 
 |      *  + the GICD enable bit for its group is set | 
 |      *  + its ACTIVE bit is not set (otherwise it would be Active+Pending) | 
 |      * Conveniently we can bulk-calculate this with bitwise operations. | 
 |      */ | 
 |     uint32_t pend, grpmask; | 
 |     uint32_t pending = *gic_bmp_ptr32(s->pending, irq); | 
 |     uint32_t edge_trigger = *gic_bmp_ptr32(s->edge_trigger, irq); | 
 |     uint32_t level = *gic_bmp_ptr32(s->level, irq); | 
 |     uint32_t group = *gic_bmp_ptr32(s->group, irq); | 
 |     uint32_t grpmod = *gic_bmp_ptr32(s->grpmod, irq); | 
 |     uint32_t enable = *gic_bmp_ptr32(s->enabled, irq); | 
 |     uint32_t active = *gic_bmp_ptr32(s->active, irq); | 
 |  | 
 |     pend = pending | (~edge_trigger & level); | 
 |     pend &= enable; | 
 |     pend &= ~active; | 
 |  | 
 |     if (s->gicd_ctlr & GICD_CTLR_DS) { | 
 |         grpmod = 0; | 
 |     } | 
 |  | 
 |     grpmask = 0; | 
 |     if (s->gicd_ctlr & GICD_CTLR_EN_GRP1NS) { | 
 |         grpmask |= group; | 
 |     } | 
 |     if (s->gicd_ctlr & GICD_CTLR_EN_GRP1S) { | 
 |         grpmask |= (~group & grpmod); | 
 |     } | 
 |     if (s->gicd_ctlr & GICD_CTLR_EN_GRP0) { | 
 |         grpmask |= (~group & ~grpmod); | 
 |     } | 
 |     pend &= grpmask; | 
 |  | 
 |     return pend; | 
 | } | 
 |  | 
 | static uint32_t gicr_int_pending(GICv3CPUState *cs) | 
 | { | 
 |     /* Recalculate which redistributor interrupts are actually pending, | 
 |      * and return a 32-bit integer which has a bit set for each interrupt | 
 |      * that is eligible to be signaled to the CPU interface. | 
 |      * | 
 |      * An interrupt is pending if: | 
 |      *  + the PENDING latch is set OR it is level triggered and the input is 1 | 
 |      *  + its ENABLE bit is set | 
 |      *  + the GICD enable bit for its group is set | 
 |      *  + its ACTIVE bit is not set (otherwise it would be Active+Pending) | 
 |      * Conveniently we can bulk-calculate this with bitwise operations. | 
 |      */ | 
 |     uint32_t pend, grpmask, grpmod; | 
 |  | 
 |     pend = cs->gicr_ipendr0 | (~cs->edge_trigger & cs->level); | 
 |     pend &= cs->gicr_ienabler0; | 
 |     pend &= ~cs->gicr_iactiver0; | 
 |  | 
 |     if (cs->gic->gicd_ctlr & GICD_CTLR_DS) { | 
 |         grpmod = 0; | 
 |     } else { | 
 |         grpmod = cs->gicr_igrpmodr0; | 
 |     } | 
 |  | 
 |     grpmask = 0; | 
 |     if (cs->gic->gicd_ctlr & GICD_CTLR_EN_GRP1NS) { | 
 |         grpmask |= cs->gicr_igroupr0; | 
 |     } | 
 |     if (cs->gic->gicd_ctlr & GICD_CTLR_EN_GRP1S) { | 
 |         grpmask |= (~cs->gicr_igroupr0 & grpmod); | 
 |     } | 
 |     if (cs->gic->gicd_ctlr & GICD_CTLR_EN_GRP0) { | 
 |         grpmask |= (~cs->gicr_igroupr0 & ~grpmod); | 
 |     } | 
 |     pend &= grpmask; | 
 |  | 
 |     return pend; | 
 | } | 
 |  | 
 | /* Update the interrupt status after state in a redistributor | 
 |  * or CPU interface has changed, but don't tell the CPU i/f. | 
 |  */ | 
 | static void gicv3_redist_update_noirqset(GICv3CPUState *cs) | 
 | { | 
 |     /* Find the highest priority pending interrupt among the | 
 |      * redistributor interrupts (SGIs and PPIs). | 
 |      */ | 
 |     bool seenbetter = false; | 
 |     uint8_t prio; | 
 |     int i; | 
 |     uint32_t pend; | 
 |  | 
 |     /* Find out which redistributor interrupts are eligible to be | 
 |      * signaled to the CPU interface. | 
 |      */ | 
 |     pend = gicr_int_pending(cs); | 
 |  | 
 |     if (pend) { | 
 |         for (i = 0; i < GIC_INTERNAL; i++) { | 
 |             if (!(pend & (1 << i))) { | 
 |                 continue; | 
 |             } | 
 |             prio = cs->gicr_ipriorityr[i]; | 
 |             if (irqbetter(cs, i, prio)) { | 
 |                 cs->hppi.irq = i; | 
 |                 cs->hppi.prio = prio; | 
 |                 seenbetter = true; | 
 |             } | 
 |         } | 
 |     } | 
 |  | 
 |     if (seenbetter) { | 
 |         cs->hppi.grp = gicv3_irq_group(cs->gic, cs, cs->hppi.irq); | 
 |     } | 
 |  | 
 |     if ((cs->gicr_ctlr & GICR_CTLR_ENABLE_LPIS) && cs->gic->lpi_enable && | 
 |         (cs->gic->gicd_ctlr & GICD_CTLR_EN_GRP1NS) && | 
 |         (cs->hpplpi.prio != 0xff)) { | 
 |         if (irqbetter(cs, cs->hpplpi.irq, cs->hpplpi.prio)) { | 
 |             cs->hppi.irq = cs->hpplpi.irq; | 
 |             cs->hppi.prio = cs->hpplpi.prio; | 
 |             cs->hppi.grp = cs->hpplpi.grp; | 
 |             seenbetter = true; | 
 |         } | 
 |     } | 
 |  | 
 |     /* If the best interrupt we just found would preempt whatever | 
 |      * was the previous best interrupt before this update, then | 
 |      * we know it's definitely the best one now. | 
 |      * If we didn't find an interrupt that would preempt the previous | 
 |      * best, and the previous best is outside our range (or there was no | 
 |      * previous pending interrupt at all), then that is still valid, and | 
 |      * we leave it as the best. | 
 |      * Otherwise, we need to do a full update (because the previous best | 
 |      * interrupt has reduced in priority and any other interrupt could | 
 |      * now be the new best one). | 
 |      */ | 
 |     if (!seenbetter && cs->hppi.prio != 0xff && | 
 |         (cs->hppi.irq < GIC_INTERNAL || | 
 |          cs->hppi.irq >= GICV3_LPI_INTID_START)) { | 
 |         gicv3_full_update_noirqset(cs->gic); | 
 |     } | 
 | } | 
 |  | 
 | /* Update the GIC status after state in a redistributor or | 
 |  * CPU interface has changed, and inform the CPU i/f of | 
 |  * its new highest priority pending interrupt. | 
 |  */ | 
 | void gicv3_redist_update(GICv3CPUState *cs) | 
 | { | 
 |     gicv3_redist_update_noirqset(cs); | 
 |     gicv3_cpuif_update(cs); | 
 | } | 
 |  | 
 | /* Update the GIC status after state in the distributor has | 
 |  * changed affecting @len interrupts starting at @start, | 
 |  * but don't tell the CPU i/f. | 
 |  */ | 
 | static void gicv3_update_noirqset(GICv3State *s, int start, int len) | 
 | { | 
 |     int i; | 
 |     uint8_t prio; | 
 |     uint32_t pend = 0; | 
 |  | 
 |     assert(start >= GIC_INTERNAL); | 
 |     assert(len > 0); | 
 |  | 
 |     for (i = 0; i < s->num_cpu; i++) { | 
 |         s->cpu[i].seenbetter = false; | 
 |     } | 
 |  | 
 |     /* Find the highest priority pending interrupt in this range. */ | 
 |     for (i = start; i < start + len; i++) { | 
 |         GICv3CPUState *cs; | 
 |  | 
 |         if (i == start || (i & 0x1f) == 0) { | 
 |             /* Calculate the next 32 bits worth of pending status */ | 
 |             pend = gicd_int_pending(s, i & ~0x1f); | 
 |         } | 
 |  | 
 |         if (!(pend & (1 << (i & 0x1f)))) { | 
 |             continue; | 
 |         } | 
 |         cs = s->gicd_irouter_target[i]; | 
 |         if (!cs) { | 
 |             /* Interrupts targeting no implemented CPU should remain pending | 
 |              * and not be forwarded to any CPU. | 
 |              */ | 
 |             continue; | 
 |         } | 
 |         prio = s->gicd_ipriority[i]; | 
 |         if (irqbetter(cs, i, prio)) { | 
 |             cs->hppi.irq = i; | 
 |             cs->hppi.prio = prio; | 
 |             cs->seenbetter = true; | 
 |         } | 
 |     } | 
 |  | 
 |     /* If the best interrupt we just found would preempt whatever | 
 |      * was the previous best interrupt before this update, then | 
 |      * we know it's definitely the best one now. | 
 |      * If we didn't find an interrupt that would preempt the previous | 
 |      * best, and the previous best is outside our range (or there was | 
 |      * no previous pending interrupt at all), then that | 
 |      * is still valid, and we leave it as the best. | 
 |      * Otherwise, we need to do a full update (because the previous best | 
 |      * interrupt has reduced in priority and any other interrupt could | 
 |      * now be the new best one). | 
 |      */ | 
 |     for (i = 0; i < s->num_cpu; i++) { | 
 |         GICv3CPUState *cs = &s->cpu[i]; | 
 |  | 
 |         if (cs->seenbetter) { | 
 |             cs->hppi.grp = gicv3_irq_group(cs->gic, cs, cs->hppi.irq); | 
 |         } | 
 |  | 
 |         if (!cs->seenbetter && cs->hppi.prio != 0xff && | 
 |             cs->hppi.irq >= start && cs->hppi.irq < start + len) { | 
 |             gicv3_full_update_noirqset(s); | 
 |             break; | 
 |         } | 
 |     } | 
 | } | 
 |  | 
 | void gicv3_update(GICv3State *s, int start, int len) | 
 | { | 
 |     int i; | 
 |  | 
 |     gicv3_update_noirqset(s, start, len); | 
 |     for (i = 0; i < s->num_cpu; i++) { | 
 |         gicv3_cpuif_update(&s->cpu[i]); | 
 |     } | 
 | } | 
 |  | 
 | void gicv3_full_update_noirqset(GICv3State *s) | 
 | { | 
 |     /* Completely recalculate the GIC status from scratch, but | 
 |      * don't update any outbound IRQ lines. | 
 |      */ | 
 |     int i; | 
 |  | 
 |     for (i = 0; i < s->num_cpu; i++) { | 
 |         s->cpu[i].hppi.prio = 0xff; | 
 |     } | 
 |  | 
 |     /* Note that we can guarantee that these functions will not | 
 |      * recursively call back into gicv3_full_update(), because | 
 |      * at each point the "previous best" is always outside the | 
 |      * range we ask them to update. | 
 |      */ | 
 |     gicv3_update_noirqset(s, GIC_INTERNAL, s->num_irq - GIC_INTERNAL); | 
 |  | 
 |     for (i = 0; i < s->num_cpu; i++) { | 
 |         gicv3_redist_update_noirqset(&s->cpu[i]); | 
 |     } | 
 | } | 
 |  | 
 | void gicv3_full_update(GICv3State *s) | 
 | { | 
 |     /* Completely recalculate the GIC status from scratch, including | 
 |      * updating outbound IRQ lines. | 
 |      */ | 
 |     int i; | 
 |  | 
 |     gicv3_full_update_noirqset(s); | 
 |     for (i = 0; i < s->num_cpu; i++) { | 
 |         gicv3_cpuif_update(&s->cpu[i]); | 
 |     } | 
 | } | 
 |  | 
 | /* Process a change in an external IRQ input. */ | 
 | static void gicv3_set_irq(void *opaque, int irq, int level) | 
 | { | 
 |     /* Meaning of the 'irq' parameter: | 
 |      *  [0..N-1] : external interrupts | 
 |      *  [N..N+31] : PPI (internal) interrupts for CPU 0 | 
 |      *  [N+32..N+63] : PPI (internal interrupts for CPU 1 | 
 |      *  ... | 
 |      */ | 
 |     GICv3State *s = opaque; | 
 |  | 
 |     if (irq < (s->num_irq - GIC_INTERNAL)) { | 
 |         /* external interrupt (SPI) */ | 
 |         gicv3_dist_set_irq(s, irq + GIC_INTERNAL, level); | 
 |     } else { | 
 |         /* per-cpu interrupt (PPI) */ | 
 |         int cpu; | 
 |  | 
 |         irq -= (s->num_irq - GIC_INTERNAL); | 
 |         cpu = irq / GIC_INTERNAL; | 
 |         irq %= GIC_INTERNAL; | 
 |         assert(cpu < s->num_cpu); | 
 |         /* Raising SGIs via this function would be a bug in how the board | 
 |          * model wires up interrupts. | 
 |          */ | 
 |         assert(irq >= GIC_NR_SGIS); | 
 |         gicv3_redist_set_irq(&s->cpu[cpu], irq, level); | 
 |     } | 
 | } | 
 |  | 
 | static void arm_gicv3_post_load(GICv3State *s) | 
 | { | 
 |     int i; | 
 |     /* Recalculate our cached idea of the current highest priority | 
 |      * pending interrupt, but don't set IRQ or FIQ lines. | 
 |      */ | 
 |     for (i = 0; i < s->num_cpu; i++) { | 
 |         gicv3_redist_update_lpi_only(&s->cpu[i]); | 
 |     } | 
 |     gicv3_full_update_noirqset(s); | 
 |     /* Repopulate the cache of GICv3CPUState pointers for target CPUs */ | 
 |     gicv3_cache_all_target_cpustates(s); | 
 | } | 
 |  | 
 | static const MemoryRegionOps gic_ops[] = { | 
 |     { | 
 |         .read_with_attrs = gicv3_dist_read, | 
 |         .write_with_attrs = gicv3_dist_write, | 
 |         .endianness = DEVICE_NATIVE_ENDIAN, | 
 |         .valid.min_access_size = 1, | 
 |         .valid.max_access_size = 8, | 
 |         .impl.min_access_size = 1, | 
 |         .impl.max_access_size = 8, | 
 |     }, | 
 |     { | 
 |         .read_with_attrs = gicv3_redist_read, | 
 |         .write_with_attrs = gicv3_redist_write, | 
 |         .endianness = DEVICE_NATIVE_ENDIAN, | 
 |         .valid.min_access_size = 1, | 
 |         .valid.max_access_size = 8, | 
 |         .impl.min_access_size = 1, | 
 |         .impl.max_access_size = 8, | 
 |     } | 
 | }; | 
 |  | 
 | static void arm_gic_realize(DeviceState *dev, Error **errp) | 
 | { | 
 |     /* Device instance realize function for the GIC sysbus device */ | 
 |     GICv3State *s = ARM_GICV3(dev); | 
 |     ARMGICv3Class *agc = ARM_GICV3_GET_CLASS(s); | 
 |     Error *local_err = NULL; | 
 |  | 
 |     agc->parent_realize(dev, &local_err); | 
 |     if (local_err) { | 
 |         error_propagate(errp, local_err); | 
 |         return; | 
 |     } | 
 |  | 
 |     gicv3_init_irqs_and_mmio(s, gicv3_set_irq, gic_ops); | 
 |  | 
 |     gicv3_init_cpuif(s); | 
 | } | 
 |  | 
 | static void arm_gicv3_class_init(ObjectClass *klass, void *data) | 
 | { | 
 |     DeviceClass *dc = DEVICE_CLASS(klass); | 
 |     ARMGICv3CommonClass *agcc = ARM_GICV3_COMMON_CLASS(klass); | 
 |     ARMGICv3Class *agc = ARM_GICV3_CLASS(klass); | 
 |  | 
 |     agcc->post_load = arm_gicv3_post_load; | 
 |     device_class_set_parent_realize(dc, arm_gic_realize, &agc->parent_realize); | 
 | } | 
 |  | 
 | static const TypeInfo arm_gicv3_info = { | 
 |     .name = TYPE_ARM_GICV3, | 
 |     .parent = TYPE_ARM_GICV3_COMMON, | 
 |     .instance_size = sizeof(GICv3State), | 
 |     .class_init = arm_gicv3_class_init, | 
 |     .class_size = sizeof(ARMGICv3Class), | 
 | }; | 
 |  | 
 | static void arm_gicv3_register_types(void) | 
 | { | 
 |     type_register_static(&arm_gicv3_info); | 
 | } | 
 |  | 
 | type_init(arm_gicv3_register_types) |