spapr: move the IRQ allocation routines under the machine

Also change the prototype to use a sPAPRMachineState and prefix them
with spapr_irq_. It will let us synchronise the IRQ allocation with
the XIVE interrupt mode when available.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

5 files changed, 125 insertions, 7 deletions

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index f1b96a4e92..53c2c58a25 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3558,6 +3558,120 @@ static ICPState *spapr_icp_get(XICSFabric *xi, int vcpu_id)
     return cpu ? ICP(cpu->intc) : NULL;
 }
 
+#define ICS_IRQ_FREE(ics, srcno)   \
+    (!((ics)->irqs[(srcno)].flags & (XICS_FLAGS_IRQ_MASK)))
+
+static int ics_find_free_block(ICSState *ics, int num, int alignnum)
+{
+    int first, i;
+
+    for (first = 0; first < ics->nr_irqs; first += alignnum) {
+        if (num > (ics->nr_irqs - first)) {
+            return -1;
+        }
+        for (i = first; i < first + num; ++i) {
+            if (!ICS_IRQ_FREE(ics, i)) {
+                break;
+            }
+        }
+        if (i == (first + num)) {
+            return first;
+        }
+    }
+
+    return -1;
+}
+
+int spapr_irq_alloc(sPAPRMachineState *spapr, int irq_hint, bool lsi,
+                    Error **errp)
+{
+    ICSState *ics = spapr->ics;
+    int irq;
+
+    if (!ics) {
+        return -1;
+    }
+    if (irq_hint) {
+        if (!ICS_IRQ_FREE(ics, irq_hint - ics->offset)) {
+            error_setg(errp, "can't allocate IRQ %d: already in use", irq_hint);
+            return -1;
+        }
+        irq = irq_hint;
+    } else {
+        irq = ics_find_free_block(ics, 1, 1);
+        if (irq < 0) {
+            error_setg(errp, "can't allocate IRQ: no IRQ left");
+            return -1;
+        }
+        irq += ics->offset;
+    }
+
+    ics_set_irq_type(ics, irq - ics->offset, lsi);
+    trace_spapr_irq_alloc(irq);
+
+    return irq;
+}
+
+/*
+ * Allocate block of consecutive IRQs, and return the number of the first IRQ in
+ * the block. If align==true, aligns the first IRQ number to num.
+ */
+int spapr_irq_alloc_block(sPAPRMachineState *spapr, int num, bool lsi,
+                          bool align, Error **errp)
+{
+    ICSState *ics = spapr->ics;
+    int i, first = -1;
+
+    if (!ics) {
+        return -1;
+    }
+
+    /*
+     * MSIMesage::data is used for storing VIRQ so
+     * it has to be aligned to num to support multiple
+     * MSI vectors. MSI-X is not affected by this.
+     * The hint is used for the first IRQ, the rest should
+     * be allocated continuously.
+     */
+    if (align) {
+        assert((num == 1) || (num == 2) || (num == 4) ||
+               (num == 8) || (num == 16) || (num == 32));
+        first = ics_find_free_block(ics, num, num);
+    } else {
+        first = ics_find_free_block(ics, num, 1);
+    }
+    if (first < 0) {
+        error_setg(errp, "can't find a free %d-IRQ block", num);
+        return -1;
+    }
+
+    for (i = first; i < first + num; ++i) {
+        ics_set_irq_type(ics, i, lsi);
+    }
+    first += ics->offset;
+
+    trace_spapr_irq_alloc_block(first, num, lsi, align);
+
+    return first;
+}
+
+void spapr_irq_free(sPAPRMachineState *spapr, int irq, int num)
+{
+    ICSState *ics = spapr->ics;
+    int srcno = irq - ics->offset;
+    int i;
+
+    if (ics_valid_irq(ics, irq)) {
+        trace_spapr_irq_free(0, irq, num);
+        for (i = srcno; i < srcno + num; ++i) {
+            if (ICS_IRQ_FREE(ics, i)) {
+                trace_spapr_irq_free_warn(0, i + ics->offset);
+            }
+            memset(&ics->irqs[i], 0, sizeof(ICSIRQState));
+        }
+    }
+}
+
 static void spapr_pic_print_info(InterruptStatsProvider *obj,
                                  Monitor *mon)
 {
diff --git a/hw/ppc/spapr_events.c b/hw/ppc/spapr_events.c
index e377fc7dde..cead596f3e 100644
--- a/hw/ppc/spapr_events.c
+++ b/hw/ppc/spapr_events.c
@@ -718,7 +718,7 @@ void spapr_events_init(sPAPRMachineState *spapr)
     spapr->event_sources = spapr_event_sources_new();
 
     spapr_event_sources_register(spapr->event_sources, EVENT_CLASS_EPOW,
-                                 spapr_ics_alloc(spapr->ics, 0, false,
+                                 spapr_irq_alloc(spapr, 0, false,
                                                   &error_fatal));
 
     /* NOTE: if machine supports modern/dedicated hotplug event source,
@@ -731,7 +731,7 @@ void spapr_events_init(sPAPRMachineState *spapr)
      */
     if (spapr->use_hotplug_event_source) {
         spapr_event_sources_register(spapr->event_sources, EVENT_CLASS_HOT_PLUG,
-                                     spapr_ics_alloc(spapr->ics, 0, false,
+                                     spapr_irq_alloc(spapr, 0, false,
                                                       &error_fatal));
     }
 
diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
index 5a3122a9f9..e0ef77a480 100644
--- a/hw/ppc/spapr_pci.c
+++ b/hw/ppc/spapr_pci.c
@@ -314,7 +314,7 @@ static void rtas_ibm_change_msi(PowerPCCPU *cpu, sPAPRMachineState *spapr,
             return;
         }
 
-        spapr_ics_free(spapr->ics, msi->first_irq, msi->num);
+        spapr_irq_free(spapr, msi->first_irq, msi->num);
         if (msi_present(pdev)) {
             spapr_msi_setmsg(pdev, 0, false, 0, 0);
         }
@@ -352,7 +352,7 @@ static void rtas_ibm_change_msi(PowerPCCPU *cpu, sPAPRMachineState *spapr,
     }
 
     /* Allocate MSIs */
-    irq = spapr_ics_alloc_block(spapr->ics, req_num, false,
+    irq = spapr_irq_alloc_block(spapr, req_num, false,
                            ret_intr_type == RTAS_TYPE_MSI, &err);
     if (err) {
         error_reportf_err(err, "Can't allocate MSIs for device %x: ",
@@ -363,7 +363,7 @@ static void rtas_ibm_change_msi(PowerPCCPU *cpu, sPAPRMachineState *spapr,
 
     /* Release previous MSIs */
     if (msi) {
-        spapr_ics_free(spapr->ics, msi->first_irq, msi->num);
+        spapr_irq_free(spapr, msi->first_irq, msi->num);
         g_hash_table_remove(phb->msi, &config_addr);
     }
 
@@ -1675,7 +1675,7 @@ static void spapr_phb_realize(DeviceState *dev, Error **errp)
         uint32_t irq;
         Error *local_err = NULL;
 
-        irq = spapr_ics_alloc_block(spapr->ics, 1, true, false, &local_err);
+        irq = spapr_irq_alloc_block(spapr, 1, true, false, &local_err);
         if (local_err) {
             error_propagate(errp, local_err);
             error_prepend(errp, "can't allocate LSIs: ");
diff --git a/hw/ppc/spapr_vio.c b/hw/ppc/spapr_vio.c
index ea3bc8bd9e..bb7ed2c537 100644
--- a/hw/ppc/spapr_vio.c
+++ b/hw/ppc/spapr_vio.c
@@ -454,7 +454,7 @@ static void spapr_vio_busdev_realize(DeviceState *qdev, Error **errp)
         dev->qdev.id = id;
     }
 
-    dev->irq = spapr_ics_alloc(spapr->ics, dev->irq, false, &local_err);
+    dev->irq = spapr_irq_alloc(spapr, dev->irq, false, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         return;
diff --git a/hw/ppc/trace-events b/hw/ppc/trace-events
index 4a6a6490fa..b7c3e64b5e 100644
--- a/hw/ppc/trace-events
+++ b/hw/ppc/trace-events
@@ -12,6 +12,10 @@ spapr_pci_msi_retry(unsigned config_addr, unsigned req_num, unsigned max_irqs) "
 # hw/ppc/spapr.c
 spapr_cas_failed(unsigned long n) "DT diff buffer is too small: %ld bytes"
 spapr_cas_continue(unsigned long n) "Copy changes to the guest: %ld bytes"
+spapr_irq_alloc(int irq) "irq %d"
+spapr_irq_alloc_block(int first, int num, bool lsi, int align) "first irq %d, %d irqs, lsi=%d, alignnum %d"
+spapr_irq_free(int src, int irq, int num) "Source#%d, first irq %d, %d irqs"
+spapr_irq_free_warn(int src, int irq) "Source#%d, irq %d is already free"
 
 # hw/ppc/spapr_hcall.c
 spapr_cas_pvr_try(uint32_t pvr) "0x%x"