From 9f1d4b1d6939d39fe570d886f6a651f4764bcbcb Mon Sep 17 00:00:00 2001 From: Scott Wood Date: Thu, 3 Jan 2013 13:25:40 +0000 Subject: openpic: fix CTPR and de-assertion of interrupts Properly implement level-triggered interrupts by withdrawing an interrupt from the raised queue if the interrupt source de-asserts. Also withdraw from the raised queue if the interrupt becomes masked. When CTPR is written, check whether we need to raise or lower the interrupt output. Signed-off-by: Scott Wood Signed-off-by: Alexander Graf --- hw/openpic.c | 181 ++++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 123 insertions(+), 58 deletions(-) diff --git a/hw/openpic.c b/hw/openpic.c index 374f80e880..e773d680f4 100644 --- a/hw/openpic.c +++ b/hw/openpic.c @@ -213,6 +213,9 @@ typedef struct IRQDest { IRQQueue raised; IRQQueue servicing; qemu_irq *irqs; + + /* Count of IRQ sources asserting on non-INT outputs */ + uint32_t outputs_active[OPENPIC_OUTPUT_NB]; } IRQDest; typedef struct OpenPICState { @@ -308,7 +311,8 @@ static int IRQ_get_next(OpenPICState *opp, IRQQueue *q) return q->next; } -static void IRQ_local_pipe(OpenPICState *opp, int n_CPU, int n_IRQ) +static void IRQ_local_pipe(OpenPICState *opp, int n_CPU, int n_IRQ, + bool active, bool was_active) { IRQDest *dst; IRQSource *src; @@ -317,79 +321,113 @@ static void IRQ_local_pipe(OpenPICState *opp, int n_CPU, int n_IRQ) dst = &opp->dst[n_CPU]; src = &opp->src[n_IRQ]; + DPRINTF("%s: IRQ %d active %d was %d\n", + __func__, n_IRQ, active, was_active); + if (src->output != OPENPIC_OUTPUT_INT) { + DPRINTF("%s: output %d irq %d active %d was %d count %d\n", + __func__, src->output, n_IRQ, active, was_active, + dst->outputs_active[src->output]); + /* On Freescale MPIC, critical interrupts ignore priority, * IACK, EOI, etc. Before MPIC v4.1 they also ignore * masking. */ - src->ivpr |= IVPR_ACTIVITY_MASK; - DPRINTF("%s: Raise OpenPIC output %d cpu %d irq %d\n", - __func__, src->output, n_CPU, n_IRQ); - qemu_irq_raise(opp->dst[n_CPU].irqs[src->output]); + if (active) { + if (!was_active && dst->outputs_active[src->output]++ == 0) { + DPRINTF("%s: Raise OpenPIC output %d cpu %d irq %d\n", + __func__, src->output, n_CPU, n_IRQ); + qemu_irq_raise(dst->irqs[src->output]); + } + } else { + if (was_active && --dst->outputs_active[src->output] == 0) { + DPRINTF("%s: Lower OpenPIC output %d cpu %d irq %d\n", + __func__, src->output, n_CPU, n_IRQ); + qemu_irq_lower(dst->irqs[src->output]); + } + } + return; } priority = IVPR_PRIORITY(src->ivpr); - if (priority <= dst->ctpr) { - /* Too low priority */ - DPRINTF("%s: IRQ %d has too low priority on CPU %d\n", - __func__, n_IRQ, n_CPU); - return; - } - if (IRQ_testbit(&dst->raised, n_IRQ)) { - /* Interrupt miss */ - DPRINTF("%s: IRQ %d was missed on CPU %d\n", - __func__, n_IRQ, n_CPU); - return; - } - src->ivpr |= IVPR_ACTIVITY_MASK; - IRQ_setbit(&dst->raised, n_IRQ); - if (priority < dst->raised.priority) { - /* An higher priority IRQ is already raised */ - DPRINTF("%s: IRQ %d is hidden by raised IRQ %d on CPU %d\n", - __func__, n_IRQ, dst->raised.next, n_CPU); - return; + + /* Even if the interrupt doesn't have enough priority, + * it is still raised, in case ctpr is lowered later. + */ + if (active) { + IRQ_setbit(&dst->raised, n_IRQ); + } else { + IRQ_resetbit(&dst->raised, n_IRQ); } + IRQ_check(opp, &dst->raised); - if (IRQ_get_next(opp, &dst->servicing) != -1 && - priority <= dst->servicing.priority) { - DPRINTF("%s: IRQ %d is hidden by servicing IRQ %d on CPU %d\n", - __func__, n_IRQ, dst->servicing.next, n_CPU); - /* Already servicing a higher priority IRQ */ - return; + + if (active && priority <= dst->ctpr) { + DPRINTF("%s: IRQ %d priority %d too low for ctpr %d on CPU %d\n", + __func__, n_IRQ, priority, dst->ctpr, n_CPU); + active = 0; + } + + if (active) { + if (IRQ_get_next(opp, &dst->servicing) >= 0 && + priority <= dst->servicing.priority) { + DPRINTF("%s: IRQ %d is hidden by servicing IRQ %d on CPU %d\n", + __func__, n_IRQ, dst->servicing.next, n_CPU); + } else { + DPRINTF("%s: Raise OpenPIC INT output cpu %d irq %d/%d\n", + __func__, n_CPU, n_IRQ, dst->raised.next); + qemu_irq_raise(opp->dst[n_CPU].irqs[OPENPIC_OUTPUT_INT]); + } + } else { + IRQ_get_next(opp, &dst->servicing); + if (dst->raised.priority > dst->ctpr && + dst->raised.priority > dst->servicing.priority) { + DPRINTF("%s: IRQ %d inactive, IRQ %d prio %d above %d/%d, CPU %d\n", + __func__, n_IRQ, dst->raised.next, dst->raised.priority, + dst->ctpr, dst->servicing.priority, n_CPU); + /* IRQ line stays asserted */ + } else { + DPRINTF("%s: IRQ %d inactive, current prio %d/%d, CPU %d\n", + __func__, n_IRQ, dst->ctpr, dst->servicing.priority, n_CPU); + qemu_irq_lower(opp->dst[n_CPU].irqs[OPENPIC_OUTPUT_INT]); + } } - DPRINTF("Raise OpenPIC INT output cpu %d irq %d\n", n_CPU, n_IRQ); - qemu_irq_raise(opp->dst[n_CPU].irqs[OPENPIC_OUTPUT_INT]); } /* update pic state because registers for n_IRQ have changed value */ static void openpic_update_irq(OpenPICState *opp, int n_IRQ) { IRQSource *src; + bool active, was_active; int i; src = &opp->src[n_IRQ]; + active = src->pending; - if (!src->pending) { - /* no irq pending */ - DPRINTF("%s: IRQ %d is not pending\n", __func__, n_IRQ); - return; - } if ((src->ivpr & IVPR_MASK_MASK) && !src->nomask) { /* Interrupt source is disabled */ DPRINTF("%s: IRQ %d is disabled\n", __func__, n_IRQ); - return; + active = false; } - if (IVPR_PRIORITY(src->ivpr) == 0) { - /* Priority set to zero */ - DPRINTF("%s: IRQ %d has 0 priority\n", __func__, n_IRQ); + + was_active = !!(src->ivpr & IVPR_ACTIVITY_MASK); + + /* + * We don't have a similar check for already-active because + * ctpr may have changed and we need to withdraw the interrupt. + */ + if (!active && !was_active) { + DPRINTF("%s: IRQ %d is already inactive\n", __func__, n_IRQ); return; } - if (src->ivpr & IVPR_ACTIVITY_MASK) { - /* IRQ already active */ - DPRINTF("%s: IRQ %d is already active\n", __func__, n_IRQ); - return; + + if (active) { + src->ivpr |= IVPR_ACTIVITY_MASK; + } else { + src->ivpr &= ~IVPR_ACTIVITY_MASK; } + if (src->idr == 0) { /* No target */ DPRINTF("%s: IRQ %d has no target\n", __func__, n_IRQ); @@ -398,12 +436,12 @@ static void openpic_update_irq(OpenPICState *opp, int n_IRQ) if (src->idr == (1 << src->last_cpu)) { /* Only one CPU is allowed to receive this IRQ */ - IRQ_local_pipe(opp, src->last_cpu, n_IRQ); + IRQ_local_pipe(opp, src->last_cpu, n_IRQ, active, was_active); } else if (!(src->ivpr & IVPR_MODE_MASK)) { /* Directed delivery mode */ for (i = 0; i < opp->nb_cpus; i++) { if (src->destmask & (1 << i)) { - IRQ_local_pipe(opp, i, n_IRQ); + IRQ_local_pipe(opp, i, n_IRQ, active, was_active); } } } else { @@ -413,7 +451,7 @@ static void openpic_update_irq(OpenPICState *opp, int n_IRQ) i = 0; } if (src->destmask & (1 << i)) { - IRQ_local_pipe(opp, i, n_IRQ); + IRQ_local_pipe(opp, i, n_IRQ, active, was_active); src->last_cpu = i; break; } @@ -437,16 +475,25 @@ static void openpic_set_irq(void *opaque, int n_IRQ, int level) if (src->level) { /* level-sensitive irq */ src->pending = level; - if (!level) { - src->ivpr &= ~IVPR_ACTIVITY_MASK; - } + openpic_update_irq(opp, n_IRQ); } else { /* edge-sensitive irq */ if (level) { src->pending = 1; + openpic_update_irq(opp, n_IRQ); + } + + if (src->output != OPENPIC_OUTPUT_INT) { + /* Edge-triggered interrupts shouldn't be used + * with non-INT delivery, but just in case, + * try to make it do something sane rather than + * cause an interrupt storm. This is close to + * what you'd probably see happen in real hardware. + */ + src->pending = 0; + openpic_update_irq(opp, n_IRQ); } } - openpic_update_irq(opp, n_IRQ); } static void openpic_reset(DeviceState *d) @@ -934,6 +981,21 @@ static void openpic_cpu_write_internal(void *opaque, hwaddr addr, break; case 0x80: /* CTPR */ dst->ctpr = val & 0x0000000F; + + DPRINTF("%s: set CPU %d ctpr to %d, raised %d servicing %d\n", + __func__, idx, dst->ctpr, dst->raised.priority, + dst->servicing.priority); + + if (dst->raised.priority <= dst->ctpr) { + DPRINTF("%s: Lower OpenPIC INT output cpu %d due to ctpr\n", + __func__, idx); + qemu_irq_lower(dst->irqs[OPENPIC_OUTPUT_INT]); + } else if (dst->raised.priority > dst->servicing.priority) { + DPRINTF("%s: Raise OpenPIC INT output cpu %d irq %d\n", + __func__, idx, dst->raised.next); + qemu_irq_raise(dst->irqs[OPENPIC_OUTPUT_INT]); + } + break; case 0x90: /* WHOAMI */ /* Read-only register */ @@ -995,22 +1057,21 @@ static uint32_t openpic_iack(OpenPICState *opp, IRQDest *dst, int cpu) src = &opp->src[irq]; if (!(src->ivpr & IVPR_ACTIVITY_MASK) || !(IVPR_PRIORITY(src->ivpr) > dst->ctpr)) { - /* - Spurious level-sensitive IRQ - * - Priorities has been changed - * and the pending IRQ isn't allowed anymore - */ - src->ivpr &= ~IVPR_ACTIVITY_MASK; + fprintf(stderr, "%s: bad raised IRQ %d ctpr %d ivpr 0x%08x\n", + __func__, irq, dst->ctpr, src->ivpr); + openpic_update_irq(opp, irq); retval = opp->spve; } else { /* IRQ enter servicing state */ IRQ_setbit(&dst->servicing, irq); retval = IVPR_VECTOR(opp, src->ivpr); } - IRQ_resetbit(&dst->raised, irq); + if (!src->level) { /* edge-sensitive IRQ */ src->ivpr &= ~IVPR_ACTIVITY_MASK; src->pending = 0; + IRQ_resetbit(&dst->raised, irq); } if ((irq >= opp->irq_ipi0) && (irq < (opp->irq_ipi0 + MAX_IPI))) { @@ -1208,6 +1269,8 @@ static void openpic_save(QEMUFile* f, void *opaque) qemu_put_sbe32s(f, &opp->dst[i].ctpr); openpic_save_IRQ_queue(f, &opp->dst[i].raised); openpic_save_IRQ_queue(f, &opp->dst[i].servicing); + qemu_put_buffer(f, (uint8_t *)&opp->dst[i].outputs_active, + sizeof(opp->dst[i].outputs_active)); } for (i = 0; i < MAX_TMR; i++) { @@ -1264,6 +1327,8 @@ static int openpic_load(QEMUFile* f, void *opaque, int version_id) qemu_get_sbe32s(f, &opp->dst[i].ctpr); openpic_load_IRQ_queue(f, &opp->dst[i].raised); openpic_load_IRQ_queue(f, &opp->dst[i].servicing); + qemu_get_buffer(f, (uint8_t *)&opp->dst[i].outputs_active, + sizeof(opp->dst[i].outputs_active)); } for (i = 0; i < MAX_TMR; i++) { -- cgit v1.2.3