spapr/irq: introduce a spapr_irq_init_device() helper

The way the XICS and the XIVE devices are initialized follows the same
pattern. First, try to connect to the KVM device and if not possible
fallback on the emulated device, unless a kernel_irqchip is required.
The spapr_irq_init_device() routine implements this sequence in
generic way using new sPAPR IRQ handlers ->init_emu() and ->init_kvm().

The XIVE init sequence is moved under the associated sPAPR IRQ
->init() handler. This will change again when KVM support is added for
the dual interrupt mode.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20190513084245.25755-12-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/intc/spapr_xive.c

@@ -281,7 +281,6 @@ static void spapr_xive_realize(DeviceState *dev, Error **errp)
     XiveSource *xsrc = &xive->source;
     XiveENDSource *end_xsrc = &xive->end_source;
     Error *local_err = NULL;
-    MachineState *machine = MACHINE(qdev_get_machine());
 
     if (!xive->nr_irqs) {
         error_setg(errp, "Number of interrupt needs to be greater 0");
@@ -332,27 +331,12 @@ static void spapr_xive_realize(DeviceState *dev, Error **errp)
                            xive->tm_base + XIVE_TM_USER_PAGE * (1 << TM_SHIFT));
 
     qemu_register_reset(spapr_xive_reset, dev);
+}
 
-    if (kvm_enabled() && machine_kernel_irqchip_allowed(machine)) {
-        kvmppc_xive_connect(xive, &local_err);
-        if (local_err && machine_kernel_irqchip_required(machine)) {
-            error_prepend(&local_err,
-                          "kernel_irqchip requested but unavailable: ");
-            error_propagate(errp, local_err);
-            return;
-        }
-
-        if (!local_err) {
-            return;
-        }
-
-        /*
-         * We failed to initialize the XIVE KVM device, fallback to
-         * emulated mode
-         */
-        error_prepend(&local_err, "kernel_irqchip allowed but unavailable: ");
-        warn_report_err(local_err);
-    }
+void spapr_xive_init(SpaprXive *xive, Error **errp)
+{
+    XiveSource *xsrc = &xive->source;
+    XiveENDSource *end_xsrc = &xive->end_source;
 
     /* TIMA initialization */
     memory_region_init_io(&xive->tm_mmio, OBJECT(xive), &xive_tm_ops, xive,

hw/ppc/spapr_irq.c

@@ -62,6 +62,35 @@ void spapr_irq_msi_reset(SpaprMachineState *spapr)
     bitmap_clear(spapr->irq_map, 0, spapr->irq_map_nr);
 }
 
+static void spapr_irq_init_device(SpaprMachineState *spapr,
+                                  SpaprIrq *irq, Error **errp)
+{
+    MachineState *machine = MACHINE(spapr);
+    Error *local_err = NULL;
+
+    if (kvm_enabled() && machine_kernel_irqchip_allowed(machine)) {
+        irq->init_kvm(spapr, &local_err);
+        if (local_err && machine_kernel_irqchip_required(machine)) {
+            error_prepend(&local_err,
+                          "kernel_irqchip requested but unavailable: ");
+            error_propagate(errp, local_err);
+            return;
+        }
+
+        if (!local_err) {
+            return;
+        }
+
+        /*
+         * We failed to initialize the KVM device, fallback to
+         * emulated mode
+         */
+        error_prepend(&local_err, "kernel_irqchip allowed but unavailable: ");
+        warn_report_err(local_err);
+    }
+
+    irq->init_emu(spapr, errp);
+}
 
 /*
  * XICS IRQ backend.
@@ -70,28 +99,13 @@ void spapr_irq_msi_reset(SpaprMachineState *spapr)
 static void spapr_irq_init_xics(SpaprMachineState *spapr, int nr_irqs,
                                 Error **errp)
 {
-    MachineState *machine = MACHINE(spapr);
     Object *obj;
     Error *local_err = NULL;
-    bool xics_kvm = false;
 
-    if (kvm_enabled()) {
-        if (machine_kernel_irqchip_allowed(machine) &&
-            !xics_kvm_init(spapr, &local_err)) {
-            xics_kvm = true;
-        }
-        if (machine_kernel_irqchip_required(machine) && !xics_kvm) {
-            error_prepend(&local_err,
-                          "kernel_irqchip requested but unavailable: ");
-            error_propagate(errp, local_err);
-            return;
-        }
-        error_free(local_err);
-        local_err = NULL;
-    }
-
-    if (!xics_kvm) {
-        xics_spapr_init(spapr);
+    spapr_irq_init_device(spapr, &spapr_irq_xics, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
     }
 
     obj = object_new(TYPE_ICS_SIMPLE);
@@ -220,6 +234,18 @@ static const char *spapr_irq_get_nodename_xics(SpaprMachineState *spapr)
     return XICS_NODENAME;
 }
 
+static void spapr_irq_init_emu_xics(SpaprMachineState *spapr, Error **errp)
+{
+    xics_spapr_init(spapr);
+}
+
+static void spapr_irq_init_kvm_xics(SpaprMachineState *spapr, Error **errp)
+{
+    if (kvm_enabled()) {
+        xics_kvm_init(spapr, errp);
+    }
+}
+
 #define SPAPR_IRQ_XICS_NR_IRQS     0x1000
 #define SPAPR_IRQ_XICS_NR_MSIS     \
     (XICS_IRQ_BASE + SPAPR_IRQ_XICS_NR_IRQS - SPAPR_IRQ_MSI)
@@ -240,6 +266,8 @@ SpaprIrq spapr_irq_xics = {
     .reset       = spapr_irq_reset_xics,
     .set_irq     = spapr_irq_set_irq_xics,
     .get_nodename = spapr_irq_get_nodename_xics,
+    .init_emu    = spapr_irq_init_emu_xics,
+    .init_kvm    = spapr_irq_init_kvm_xics,
 };
 
 /*
@@ -251,6 +279,7 @@ static void spapr_irq_init_xive(SpaprMachineState *spapr, int nr_irqs,
     uint32_t nr_servers = spapr_max_server_number(spapr);
     DeviceState *dev;
     int i;
+    Error *local_err = NULL;
 
     dev = qdev_create(NULL, TYPE_SPAPR_XIVE);
     qdev_prop_set_uint32(dev, "nr-irqs", nr_irqs);
@@ -268,6 +297,12 @@ static void spapr_irq_init_xive(SpaprMachineState *spapr, int nr_irqs,
     }
 
     spapr_xive_hcall_init(spapr);
+
+    spapr_irq_init_device(spapr, &spapr_irq_xive, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
 }
 
 static int spapr_irq_claim_xive(SpaprMachineState *spapr, int irq, bool lsi,
@@ -375,6 +410,18 @@ static const char *spapr_irq_get_nodename_xive(SpaprMachineState *spapr)
     return spapr->xive->nodename;
 }
 
+static void spapr_irq_init_emu_xive(SpaprMachineState *spapr, Error **errp)
+{
+    spapr_xive_init(spapr->xive, errp);
+}
+
+static void spapr_irq_init_kvm_xive(SpaprMachineState *spapr, Error **errp)
+{
+    if (kvm_enabled()) {
+        kvmppc_xive_connect(spapr->xive, errp);
+    }
+}
+
 /*
  * XIVE uses the full IRQ number space. Set it to 8K to be compatible
  * with XICS.
@@ -399,6 +446,8 @@ SpaprIrq spapr_irq_xive = {
     .reset       = spapr_irq_reset_xive,
     .set_irq     = spapr_irq_set_irq_xive,
     .get_nodename = spapr_irq_get_nodename_xive,
+    .init_emu    = spapr_irq_init_emu_xive,
+    .init_kvm    = spapr_irq_init_kvm_xive,
 };
 
 /*
@@ -560,6 +609,8 @@ SpaprIrq spapr_irq_dual = {
     .reset       = spapr_irq_reset_dual,
     .set_irq     = spapr_irq_set_irq_dual,
     .get_nodename = spapr_irq_get_nodename_dual,
+    .init_emu    = NULL, /* should not be used */
+    .init_kvm    = NULL, /* should not be used */
 };
 
 

include/hw/ppc/spapr_irq.h

@@ -48,6 +48,8 @@ typedef struct SpaprIrq {
     void (*reset)(SpaprMachineState *spapr, Error **errp);
     void (*set_irq)(void *opaque, int srcno, int val);
     const char *(*get_nodename)(SpaprMachineState *spapr);
+    void (*init_emu)(SpaprMachineState *spapr, Error **errp);
+    void (*init_kvm)(SpaprMachineState *spapr, Error **errp);
 } SpaprIrq;
 
 extern SpaprIrq spapr_irq_xics;

include/hw/ppc/spapr_xive.h

@@ -66,6 +66,7 @@ void spapr_xive_map_mmio(SpaprXive *xive);
 
 int spapr_xive_end_to_target(uint8_t end_blk, uint32_t end_idx,
                              uint32_t *out_server, uint8_t *out_prio);
+void spapr_xive_init(SpaprXive *xive, Error **errp);
 
 /*
  * KVM XIVE device helpers