*/
vcpu->arch.xive_esc_on = false;
+ /* This orders xive_esc_on = false vs. subsequent stale_p = true */
+ smp_wmb(); /* goes with smp_mb() in cleanup_single_escalation */
+
return IRQ_HANDLED;
}
vcpu->arch.xive_esc_raddr = 0;
}
+/*
+ * In single escalation mode, the escalation interrupt is marked so
+ * that EOI doesn't re-enable it, but just sets the stale_p flag to
+ * indicate that the P bit has already been dealt with. However, the
+ * assembly code that enters the guest sets PQ to 00 without clearing
+ * stale_p (because it has no easy way to address it). Hence we have
+ * to adjust stale_p before shutting down the interrupt.
+ */
+void xive_cleanup_single_escalation(struct kvm_vcpu *vcpu,
+ struct kvmppc_xive_vcpu *xc, int irq)
+{
+ struct irq_data *d = irq_get_irq_data(irq);
+ struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
+
+ /*
+ * This slightly odd sequence gives the right result
+ * (i.e. stale_p set if xive_esc_on is false) even if
+ * we race with xive_esc_irq() and xive_irq_eoi().
+ */
+ xd->stale_p = false;
+ smp_mb(); /* paired with smb_wmb in xive_esc_irq */
+ if (!vcpu->arch.xive_esc_on)
+ xd->stale_p = true;
+}
+
void kvmppc_xive_cleanup_vcpu(struct kvm_vcpu *vcpu)
{
struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
/* Free escalations */
for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) {
if (xc->esc_virq[i]) {
+ if (xc->xive->single_escalation)
+ xive_cleanup_single_escalation(vcpu, xc,
+ xc->esc_virq[i]);
free_irq(xc->esc_virq[i], vcpu);
irq_dispose_mapping(xc->esc_virq[i]);
kfree(xc->esc_virq_names[i]);
static u32 xive_scan_interrupts(struct xive_cpu *xc, bool just_peek)
{
u32 irq = 0;
- u8 prio;
+ u8 prio = 0;
/* Find highest pending priority */
while (xc->pending_prio != 0) {
irq = xive_read_eq(&xc->queue[prio], just_peek);
/* Found something ? That's it */
- if (irq)
- break;
+ if (irq) {
+ if (just_peek || irq_to_desc(irq))
+ break;
+ /*
+ * We should never get here; if we do then we must
+ * have failed to synchronize the interrupt properly
+ * when shutting it down.
+ */
+ pr_crit("xive: got interrupt %d without descriptor, dropping\n",
+ irq);
+ WARN_ON(1);
+ continue;
+ }
/* Clear pending bits */
xc->pending_prio &= ~(1 << prio);
*/
static void xive_do_source_eoi(u32 hw_irq, struct xive_irq_data *xd)
{
+ xd->stale_p = false;
/* If the XIVE supports the new "store EOI facility, use it */
if (xd->flags & XIVE_IRQ_FLAG_STORE_EOI)
xive_esb_write(xd, XIVE_ESB_STORE_EOI, 0);
}
}
-/* irq_chip eoi callback */
+/* irq_chip eoi callback, called with irq descriptor lock held */
static void xive_irq_eoi(struct irq_data *d)
{
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
if (!irqd_irq_disabled(d) && !irqd_is_forwarded_to_vcpu(d) &&
!(xd->flags & XIVE_IRQ_NO_EOI))
xive_do_source_eoi(irqd_to_hwirq(d), xd);
+ else
+ xd->stale_p = true;
/*
* Clear saved_p to indicate that it's no longer occupying
*/
if (mask) {
val = xive_esb_read(xd, XIVE_ESB_SET_PQ_01);
- xd->saved_p = !!(val & XIVE_ESB_VAL_P);
- } else if (xd->saved_p)
+ if (!xd->stale_p && !!(val & XIVE_ESB_VAL_P))
+ xd->saved_p = true;
+ xd->stale_p = false;
+ } else if (xd->saved_p) {
xive_esb_read(xd, XIVE_ESB_SET_PQ_10);
- else
+ xd->saved_p = false;
+ } else {
xive_esb_read(xd, XIVE_ESB_SET_PQ_00);
+ xd->stale_p = false;
+ }
}
/*
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
int target, rc;
+ xd->saved_p = false;
+ xd->stale_p = false;
pr_devel("xive_irq_startup: irq %d [0x%x] data @%p\n",
d->irq, hw_irq, d);
return 0;
}
+/* called with irq descriptor lock held */
static void xive_irq_shutdown(struct irq_data *d)
{
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
xive_do_source_set_mask(xd, true);
/*
- * The above may have set saved_p. We clear it otherwise it
- * will prevent re-enabling later on. It is ok to forget the
- * fact that the interrupt might be in a queue because we are
- * accounting that already in xive_dec_target_count() and will
- * be re-routing it to a new queue with proper accounting when
- * it's started up again
- */
- xd->saved_p = false;
-
- /*
* Mask the interrupt in HW in the IVT/EAS and set the number
* to be the "bad" IRQ number
*/
return 1;
}
+/*
+ * Caller holds the irq descriptor lock, so this won't be called
+ * concurrently with xive_get_irqchip_state on the same interrupt.
+ */
static int xive_irq_set_vcpu_affinity(struct irq_data *d, void *state)
{
struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
/* Set it to PQ=10 state to prevent further sends */
pq = xive_esb_read(xd, XIVE_ESB_SET_PQ_10);
+ if (!xd->stale_p) {
+ xd->saved_p = !!(pq & XIVE_ESB_VAL_P);
+ xd->stale_p = !xd->saved_p;
+ }
/* No target ? nothing to do */
if (xd->target == XIVE_INVALID_TARGET) {
* An untargetted interrupt should have been
* also masked at the source
*/
- WARN_ON(pq & 2);
+ WARN_ON(xd->saved_p);
return 0;
}
* This saved_p is cleared by the host EOI, when we know
* for sure the queue slot is no longer in use.
*/
- if (pq & 2) {
- pq = xive_esb_read(xd, XIVE_ESB_SET_PQ_11);
- xd->saved_p = true;
+ if (xd->saved_p) {
+ xive_esb_read(xd, XIVE_ESB_SET_PQ_11);
/*
* Sync the XIVE source HW to ensure the interrupt
*/
if (xive_ops->sync_source)
xive_ops->sync_source(hw_irq);
- } else
- xd->saved_p = false;
+ }
} else {
irqd_clr_forwarded_to_vcpu(d);
return 0;
}
+/* Called with irq descriptor lock held. */
+static int xive_get_irqchip_state(struct irq_data *data,
+ enum irqchip_irq_state which, bool *state)
+{
+ struct xive_irq_data *xd = irq_data_get_irq_handler_data(data);
+
+ switch (which) {
+ case IRQCHIP_STATE_ACTIVE:
+ *state = !xd->stale_p &&
+ (xd->saved_p ||
+ !!(xive_esb_read(xd, XIVE_ESB_GET) & XIVE_ESB_VAL_P));
+ return 0;
+ default:
+ return -EINVAL;
+ }
+}
+
static struct irq_chip xive_irq_chip = {
.name = "XIVE-IRQ",
.irq_startup = xive_irq_startup,
.irq_set_type = xive_irq_set_type,
.irq_retrigger = xive_irq_retrigger,
.irq_set_vcpu_affinity = xive_irq_set_vcpu_affinity,
+ .irq_get_irqchip_state = xive_get_irqchip_state,
};
bool is_xive_irq(struct irq_chip *chip)
xd = irq_desc_get_handler_data(desc);
/*
+ * Clear saved_p to indicate that it's no longer pending
+ */
+ xd->saved_p = false;
+
+ /*
* For LSIs, we EOI, this will cause a resend if it's
* still asserted. Otherwise do an MSI retrigger.
*/
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