| /* |
| * ARM Generic Interrupt Controller v3 |
| * |
| * 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 "hw/sysbus.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 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) { |
| 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) |
| { |
| /* Recalculate our cached idea of the current highest priority |
| * pending interrupt, but don't set IRQ or FIQ lines. |
| */ |
| 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, |
| }, |
| { |
| .read_with_attrs = gicv3_redist_read, |
| .write_with_attrs = gicv3_redist_write, |
| .endianness = DEVICE_NATIVE_ENDIAN, |
| } |
| }; |
| |
| 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) |