diff options
Diffstat (limited to 'hw/intc/arm_gic.c')
| -rw-r--r-- | hw/intc/arm_gic.c | 247 |
1 files changed, 215 insertions, 32 deletions
diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c index a8c5d19448..8bad132d5a 100644 --- a/hw/intc/arm_gic.c +++ b/hw/intc/arm_gic.c @@ -219,15 +219,99 @@ static uint16_t gic_get_current_pending_irq(GICState *s, int cpu, return pending_irq; } -static void gic_set_running_irq(GICState *s, int cpu, int irq) +static int gic_get_group_priority(GICState *s, int cpu, int irq) { - s->running_irq[cpu] = irq; - if (irq == 1023) { - s->running_priority[cpu] = 0x100; + /* Return the group priority of the specified interrupt + * (which is the top bits of its priority, with the number + * of bits masked determined by the applicable binary point register). + */ + int bpr; + uint32_t mask; + + if (gic_has_groups(s) && + !(s->cpu_ctlr[cpu] & GICC_CTLR_CBPR) && + GIC_TEST_GROUP(irq, (1 << cpu))) { + bpr = s->abpr[cpu]; } else { - s->running_priority[cpu] = GIC_GET_PRIORITY(irq, cpu); + bpr = s->bpr[cpu]; } - gic_update(s); + + /* a BPR of 0 means the group priority bits are [7:1]; + * a BPR of 1 means they are [7:2], and so on down to + * a BPR of 7 meaning no group priority bits at all. + */ + mask = ~0U << ((bpr & 7) + 1); + + return GIC_GET_PRIORITY(irq, cpu) & mask; +} + +static void gic_activate_irq(GICState *s, int cpu, int irq) +{ + /* Set the appropriate Active Priority Register bit for this IRQ, + * and update the running priority. + */ + int prio = gic_get_group_priority(s, cpu, irq); + int preemption_level = prio >> (GIC_MIN_BPR + 1); + int regno = preemption_level / 32; + int bitno = preemption_level % 32; + + if (gic_has_groups(s) && GIC_TEST_GROUP(irq, (1 << cpu))) { + s->nsapr[regno][cpu] &= (1 << bitno); + } else { + s->apr[regno][cpu] &= (1 << bitno); + } + + s->running_priority[cpu] = prio; + GIC_SET_ACTIVE(irq, 1 << cpu); +} + +static int gic_get_prio_from_apr_bits(GICState *s, int cpu) +{ + /* Recalculate the current running priority for this CPU based + * on the set bits in the Active Priority Registers. + */ + int i; + for (i = 0; i < GIC_NR_APRS; i++) { + uint32_t apr = s->apr[i][cpu] | s->nsapr[i][cpu]; + if (!apr) { + continue; + } + return (i * 32 + ctz32(apr)) << (GIC_MIN_BPR + 1); + } + return 0x100; +} + +static void gic_drop_prio(GICState *s, int cpu, int group) +{ + /* Drop the priority of the currently active interrupt in the + * specified group. + * + * Note that we can guarantee (because of the requirement to nest + * GICC_IAR reads [which activate an interrupt and raise priority] + * with GICC_EOIR writes [which drop the priority for the interrupt]) + * that the interrupt we're being called for is the highest priority + * active interrupt, meaning that it has the lowest set bit in the + * APR registers. + * + * If the guest does not honour the ordering constraints then the + * behaviour of the GIC is UNPREDICTABLE, which for us means that + * the values of the APR registers might become incorrect and the + * running priority will be wrong, so interrupts that should preempt + * might not do so, and interrupts that should not preempt might do so. + */ + int i; + + for (i = 0; i < GIC_NR_APRS; i++) { + uint32_t *papr = group ? &s->nsapr[i][cpu] : &s->apr[i][cpu]; + if (!*papr) { + continue; + } + /* Clear lowest set bit */ + *papr &= *papr - 1; + break; + } + + s->running_priority[cpu] = gic_get_prio_from_apr_bits(s, cpu); } uint32_t gic_acknowledge_irq(GICState *s, int cpu, MemTxAttrs attrs) @@ -239,7 +323,7 @@ uint32_t gic_acknowledge_irq(GICState *s, int cpu, MemTxAttrs attrs) * for the case where this GIC supports grouping and the pending interrupt * is in the wrong group. */ - irq = gic_get_current_pending_irq(s, cpu, attrs);; + irq = gic_get_current_pending_irq(s, cpu, attrs); if (irq >= GIC_MAXIRQ) { DPRINTF("ACK, no pending interrupt or it is hidden: %d\n", irq); @@ -250,7 +334,6 @@ uint32_t gic_acknowledge_irq(GICState *s, int cpu, MemTxAttrs attrs) DPRINTF("ACK, pending interrupt (%d) has insufficient priority\n", irq); return 1023; } - s->last_active[irq][cpu] = s->running_irq[cpu]; if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) { /* Clear pending flags for both level and edge triggered interrupts. @@ -281,7 +364,8 @@ uint32_t gic_acknowledge_irq(GICState *s, int cpu, MemTxAttrs attrs) } } - gic_set_running_irq(s, cpu, irq); + gic_activate_irq(s, cpu, irq); + gic_update(s); DPRINTF("ACK %d\n", irq); return ret; } @@ -411,8 +495,9 @@ static uint8_t gic_get_running_priority(GICState *s, int cpu, MemTxAttrs attrs) void gic_complete_irq(GICState *s, int cpu, int irq, MemTxAttrs attrs) { - int update = 0; int cm = 1 << cpu; + int group; + DPRINTF("EOI %d\n", irq); if (irq >= s->num_irq) { /* This handles two cases: @@ -425,8 +510,9 @@ void gic_complete_irq(GICState *s, int cpu, int irq, MemTxAttrs attrs) */ return; } - if (s->running_irq[cpu] == 1023) + if (s->running_priority[cpu] == 0x100) { return; /* No active IRQ. */ + } if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) { /* Mark level triggered interrupts as pending if they are still @@ -435,11 +521,12 @@ void gic_complete_irq(GICState *s, int cpu, int irq, MemTxAttrs attrs) && GIC_TEST_LEVEL(irq, cm) && (GIC_TARGET(irq) & cm) != 0) { DPRINTF("Set %d pending mask %x\n", irq, cm); GIC_SET_PENDING(irq, cm); - update = 1; } } - if (s->security_extn && !attrs.secure && !GIC_TEST_GROUP(irq, cm)) { + group = gic_has_groups(s) && GIC_TEST_GROUP(irq, cm); + + if (s->security_extn && !attrs.secure && !group) { DPRINTF("Non-secure EOI for Group0 interrupt %d ignored\n", irq); return; } @@ -449,23 +536,9 @@ void gic_complete_irq(GICState *s, int cpu, int irq, MemTxAttrs attrs) * i.e. go ahead and complete the irq anyway. */ - if (irq != s->running_irq[cpu]) { - /* Complete an IRQ that is not currently running. */ - int tmp = s->running_irq[cpu]; - while (s->last_active[tmp][cpu] != 1023) { - if (s->last_active[tmp][cpu] == irq) { - s->last_active[tmp][cpu] = s->last_active[irq][cpu]; - break; - } - tmp = s->last_active[tmp][cpu]; - } - if (update) { - gic_update(s); - } - } else { - /* Complete the current running IRQ. */ - gic_set_running_irq(s, cpu, s->last_active[s->running_irq[cpu]][cpu]); - } + gic_drop_prio(s, cpu, group); + GIC_CLEAR_ACTIVE(irq, cm); + gic_update(s); } static uint32_t gic_dist_readb(void *opaque, hwaddr offset, MemTxAttrs attrs) @@ -922,6 +995,68 @@ static MemTxResult gic_dist_write(void *opaque, hwaddr offset, uint64_t data, } } +static inline uint32_t gic_apr_ns_view(GICState *s, int cpu, int regno) +{ + /* Return the Nonsecure view of GICC_APR<regno>. This is the + * second half of GICC_NSAPR. + */ + switch (GIC_MIN_BPR) { + case 0: + if (regno < 2) { + return s->nsapr[regno + 2][cpu]; + } + break; + case 1: + if (regno == 0) { + return s->nsapr[regno + 1][cpu]; + } + break; + case 2: + if (regno == 0) { + return extract32(s->nsapr[0][cpu], 16, 16); + } + break; + case 3: + if (regno == 0) { + return extract32(s->nsapr[0][cpu], 8, 8); + } + break; + default: + g_assert_not_reached(); + } + return 0; +} + +static inline void gic_apr_write_ns_view(GICState *s, int cpu, int regno, + uint32_t value) +{ + /* Write the Nonsecure view of GICC_APR<regno>. */ + switch (GIC_MIN_BPR) { + case 0: + if (regno < 2) { + s->nsapr[regno + 2][cpu] = value; + } + break; + case 1: + if (regno == 0) { + s->nsapr[regno + 1][cpu] = value; + } + break; + case 2: + if (regno == 0) { + s->nsapr[0][cpu] = deposit32(s->nsapr[0][cpu], 16, 16, value); + } + break; + case 3: + if (regno == 0) { + s->nsapr[0][cpu] = deposit32(s->nsapr[0][cpu], 8, 8, value); + } + break; + default: + g_assert_not_reached(); + } +} + static MemTxResult gic_cpu_read(GICState *s, int cpu, int offset, uint64_t *data, MemTxAttrs attrs) { @@ -962,8 +1097,31 @@ static MemTxResult gic_cpu_read(GICState *s, int cpu, int offset, } break; case 0xd0: case 0xd4: case 0xd8: case 0xdc: - *data = s->apr[(offset - 0xd0) / 4][cpu]; + { + int regno = (offset - 0xd0) / 4; + + if (regno >= GIC_NR_APRS || s->revision != 2) { + *data = 0; + } else if (s->security_extn && !attrs.secure) { + /* NS view of GICC_APR<n> is the top half of GIC_NSAPR<n> */ + *data = gic_apr_ns_view(s, regno, cpu); + } else { + *data = s->apr[regno][cpu]; + } break; + } + case 0xe0: case 0xe4: case 0xe8: case 0xec: + { + int regno = (offset - 0xe0) / 4; + + if (regno >= GIC_NR_APRS || s->revision != 2 || !gic_has_groups(s) || + (s->security_extn && !attrs.secure)) { + *data = 0; + } else { + *data = s->nsapr[regno][cpu]; + } + break; + } default: qemu_log_mask(LOG_GUEST_ERROR, "gic_cpu_read: Bad offset %x\n", (int)offset); @@ -1001,8 +1159,33 @@ static MemTxResult gic_cpu_write(GICState *s, int cpu, int offset, } break; case 0xd0: case 0xd4: case 0xd8: case 0xdc: - qemu_log_mask(LOG_UNIMP, "Writing APR not implemented\n"); + { + int regno = (offset - 0xd0) / 4; + + if (regno >= GIC_NR_APRS || s->revision != 2) { + return MEMTX_OK; + } + if (s->security_extn && !attrs.secure) { + /* NS view of GICC_APR<n> is the top half of GIC_NSAPR<n> */ + gic_apr_write_ns_view(s, regno, cpu, value); + } else { + s->apr[regno][cpu] = value; + } break; + } + case 0xe0: case 0xe4: case 0xe8: case 0xec: + { + int regno = (offset - 0xe0) / 4; + + if (regno >= GIC_NR_APRS || s->revision != 2) { + return MEMTX_OK; + } + if (!gic_has_groups(s) || (s->security_extn && !attrs.secure)) { + return MEMTX_OK; + } + s->nsapr[regno][cpu] = value; + break; + } default: qemu_log_mask(LOG_GUEST_ERROR, "gic_cpu_write: Bad offset %x\n", (int)offset); |