When the APLIC is emulated in the kernel, the GPIO output lines to CPUs
can be remove. In this case the APLIC trigger CPU interrupts by KVM APIs.

This patch also move the code that claim the CPU interrupts to the
beginning of APLIC realization. This can avoid the unnecessary resource
allocation before checking failed.

Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com>
---
 hw/intc/riscv_aplic.c | 49 +++++++++++++++++++++++--------------------
 1 file changed, 26 insertions(+), 23 deletions(-)

diff --git a/hw/intc/riscv_aplic.c b/hw/intc/riscv_aplic.c
index 0974c6a5db39..e5714267c096 100644
--- a/hw/intc/riscv_aplic.c
+++ b/hw/intc/riscv_aplic.c
@@ -893,6 +893,26 @@ static void riscv_aplic_realize(DeviceState *dev, Error **errp)
     RISCVAPLICState *aplic = RISCV_APLIC(dev);
 
     if (riscv_use_emulated_aplic(aplic->msimode)) {
+        /* Create output IRQ lines for non-MSI mode */
+        if (!aplic->msimode) {
+            /* Claim the CPU interrupt to be triggered by this APLIC */
+            for (i = 0; i < aplic->num_harts; i++) {
+                RISCVCPU *cpu;
+
+                cpu = RISCV_CPU(cpu_by_arch_id(aplic->hartid_base + i));
+                if (riscv_cpu_claim_interrupts(cpu,
+                    (aplic->mmode) ? MIP_MEIP : MIP_SEIP) < 0) {
+                    error_report("%s already claimed",
+                                 (aplic->mmode) ? "MEIP" : "SEIP");
+                    exit(1);
+                }
+            }
+
+            aplic->external_irqs = g_malloc(sizeof(qemu_irq) *
+                                            aplic->num_harts);
+            qdev_init_gpio_out(dev, aplic->external_irqs, aplic->num_harts);
+        }
+
         aplic->bitfield_words = (aplic->num_irqs + 31) >> 5;
         aplic->sourcecfg = g_new0(uint32_t, aplic->num_irqs);
         aplic->state = g_new0(uint32_t, aplic->num_irqs);
@@ -927,23 +947,6 @@ static void riscv_aplic_realize(DeviceState *dev, Error **errp)
         }
     }
 
-    /* Create output IRQ lines for non-MSI mode */
-    if (!aplic->msimode) {
-        aplic->external_irqs = g_malloc(sizeof(qemu_irq) * aplic->num_harts);
-        qdev_init_gpio_out(dev, aplic->external_irqs, aplic->num_harts);
-
-        /* Claim the CPU interrupt to be triggered by this APLIC */
-        for (i = 0; i < aplic->num_harts; i++) {
-            RISCVCPU *cpu = RISCV_CPU(cpu_by_arch_id(aplic->hartid_base + i));
-            if (riscv_cpu_claim_interrupts(cpu,
-                (aplic->mmode) ? MIP_MEIP : MIP_SEIP) < 0) {
-                error_report("%s already claimed",
-                             (aplic->mmode) ? "MEIP" : "SEIP");
-                exit(1);
-            }
-        }
-    }
-
     msi_nonbroken = true;
 }
 
@@ -1067,15 +1070,15 @@ DeviceState *riscv_aplic_create(hwaddr addr, hwaddr size,
 
     if (riscv_use_emulated_aplic(msimode)) {
         sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr);
-    }
 
-    if (!msimode) {
-        for (i = 0; i < num_harts; i++) {
-            CPUState *cpu = cpu_by_arch_id(hartid_base + i);
+        if (!msimode) {
+            for (i = 0; i < num_harts; i++) {
+                CPUState *cpu = cpu_by_arch_id(hartid_base + i);
 
-            qdev_connect_gpio_out_named(dev, NULL, i,
-                                        qdev_get_gpio_in(DEVICE(cpu),
+                qdev_connect_gpio_out_named(dev, NULL, i,
+                                            qdev_get_gpio_in(DEVICE(cpu),
                                             (mmode) ? IRQ_M_EXT : IRQ_S_EXT));
+            }
         }
     }
 
-- 
2.17.1