* (typically dom0).
* 2. VIRQs, typically used for timers. These are per-cpu events.
* 3. IPIs.
- * 4. Hardware interrupts. Not supported at present.
+ * 4. PIRQs - Hardware interrupts.
*
* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
*/
#include <xen/interface/hvm/hvm_op.h>
#include <xen/interface/hvm/params.h>
+/* Leave low irqs free for identity mapping */
+#define LEGACY_IRQS 16
+
/*
* This lock protects updates to the following mapping and reference-count
* arrays. The lock does not need to be acquired to read the mapping tables.
enum ipi_vector ipi;
struct {
unsigned short gsi;
- unsigned short vector;
+ unsigned char vector;
+ unsigned char flags;
} pirq;
} u;
};
+#define PIRQ_NEEDS_EOI (1 << 0)
static struct irq_info irq_info[NR_IRQS];
static struct irq_chip xen_dynamic_chip;
static struct irq_chip xen_percpu_chip;
+static struct irq_chip xen_pirq_chip;
/* Constructor for packed IRQ information. */
static struct irq_info mk_unbound_info(void)
return ret;
}
+static bool pirq_needs_eoi(unsigned irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ return info->u.pirq.flags & PIRQ_NEEDS_EOI;
+}
+
static inline unsigned long active_evtchns(unsigned int cpu,
struct shared_info *sh,
unsigned int idx)
return irq;
}
+static bool identity_mapped_irq(unsigned irq)
+{
+ /* only identity map legacy irqs */
+ return irq < LEGACY_IRQS;
+}
+
+static void pirq_unmask_notify(int irq)
+{
+ struct physdev_eoi eoi = { .irq = irq };
+
+ if (unlikely(pirq_needs_eoi(irq))) {
+ int rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
+ WARN_ON(rc);
+ }
+}
+
+static void pirq_query_unmask(int irq)
+{
+ struct physdev_irq_status_query irq_status;
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ irq_status.irq = irq;
+ if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
+ irq_status.flags = 0;
+
+ info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
+ if (irq_status.flags & XENIRQSTAT_needs_eoi)
+ info->u.pirq.flags |= PIRQ_NEEDS_EOI;
+}
+
+static bool probing_irq(int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ return desc && desc->action == NULL;
+}
+
+static unsigned int startup_pirq(unsigned int irq)
+{
+ struct evtchn_bind_pirq bind_pirq;
+ struct irq_info *info = info_for_irq(irq);
+ int evtchn = evtchn_from_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ if (VALID_EVTCHN(evtchn))
+ goto out;
+
+ bind_pirq.pirq = irq;
+ /* NB. We are happy to share unless we are probing. */
+ bind_pirq.flags = probing_irq(irq) ? 0 : BIND_PIRQ__WILL_SHARE;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq) != 0) {
+ if (!probing_irq(irq))
+ printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
+ irq);
+ return 0;
+ }
+ evtchn = bind_pirq.port;
+
+ pirq_query_unmask(irq);
+
+ evtchn_to_irq[evtchn] = irq;
+ bind_evtchn_to_cpu(evtchn, 0);
+ info->evtchn = evtchn;
+
+out:
+ unmask_evtchn(evtchn);
+ pirq_unmask_notify(irq);
+
+ return 0;
+}
+
+static void shutdown_pirq(unsigned int irq)
+{
+ struct evtchn_close close;
+ struct irq_info *info = info_for_irq(irq);
+ int evtchn = evtchn_from_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ if (!VALID_EVTCHN(evtchn))
+ return;
+
+ mask_evtchn(evtchn);
+
+ close.port = evtchn;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
+ BUG();
+
+ bind_evtchn_to_cpu(evtchn, 0);
+ evtchn_to_irq[evtchn] = -1;
+ info->evtchn = 0;
+}
+
+static void enable_pirq(unsigned int irq)
+{
+ startup_pirq(irq);
+}
+
+static void disable_pirq(unsigned int irq)
+{
+}
+
+static void ack_pirq(unsigned int irq)
+{
+ int evtchn = evtchn_from_irq(irq);
+
+ move_native_irq(irq);
+
+ if (VALID_EVTCHN(evtchn)) {
+ mask_evtchn(evtchn);
+ clear_evtchn(evtchn);
+ }
+}
+
+static void end_pirq(unsigned int irq)
+{
+ int evtchn = evtchn_from_irq(irq);
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ if (WARN_ON(!desc))
+ return;
+
+ if ((desc->status & (IRQ_DISABLED|IRQ_PENDING)) ==
+ (IRQ_DISABLED|IRQ_PENDING)) {
+ shutdown_pirq(irq);
+ } else if (VALID_EVTCHN(evtchn)) {
+ unmask_evtchn(evtchn);
+ pirq_unmask_notify(irq);
+ }
+}
+
+static int find_irq_by_gsi(unsigned gsi)
+{
+ int irq;
+
+ for (irq = 0; irq < NR_IRQS; irq++) {
+ struct irq_info *info = info_for_irq(irq);
+
+ if (info == NULL || info->type != IRQT_PIRQ)
+ continue;
+
+ if (gsi_from_irq(irq) == gsi)
+ return irq;
+ }
+
+ return -1;
+}
+
+/*
+ * Allocate a physical irq, along with a vector. We don't assign an
+ * event channel until the irq actually started up. Return an
+ * existing irq if we've already got one for the gsi.
+ */
+int xen_allocate_pirq(unsigned gsi)
+{
+ int irq;
+ struct physdev_irq irq_op;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ irq = find_irq_by_gsi(gsi);
+ if (irq != -1) {
+ printk(KERN_INFO "xen_allocate_pirq: returning irq %d for gsi %u\n",
+ irq, gsi);
+ goto out; /* XXX need refcount? */
+ }
+
+ if (identity_mapped_irq(gsi)) {
+ irq = gsi;
+ dynamic_irq_init(irq);
+ } else
+ irq = find_unbound_irq();
+
+ set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
+ handle_level_irq, "pirq");
+
+ irq_op.irq = irq;
+ if (HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
+ dynamic_irq_cleanup(irq);
+ irq = -ENOSPC;
+ goto out;
+ }
+
+ irq_info[irq] = mk_pirq_info(0, gsi, irq_op.vector);
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+
+ return irq;
+}
+
+int xen_vector_from_irq(unsigned irq)
+{
+ return vector_from_irq(irq);
+}
+
+int xen_gsi_from_irq(unsigned irq)
+{
+ return gsi_from_irq(irq);
+}
+
int bind_evtchn_to_irq(unsigned int evtchn)
{
int irq;
.retrigger = retrigger_dynirq,
};
+static struct irq_chip xen_pirq_chip __read_mostly = {
+ .name = "xen-pirq",
+
+ .startup = startup_pirq,
+ .shutdown = shutdown_pirq,
+
+ .enable = enable_pirq,
+ .unmask = enable_pirq,
+
+ .disable = disable_pirq,
+ .mask = disable_pirq,
+
+ .ack = ack_pirq,
+ .end = end_pirq,
+
+ .set_affinity = set_affinity_irq,
+
+ .retrigger = retrigger_dynirq,
+};
+
static struct irq_chip xen_percpu_chip __read_mostly = {
.name = "xen-percpu",
projects / firefly-linux-kernel-4.4.55.git / blobdiff