[PATCH v4 2/3] Add dintc kvm_irqchip_in_kernel support

Function kvm_dintc_realize() is added if kvm_irqchip_in_kernel is
set. It is to create and initialize DINTC device in kernel mode.
and use kvm_irqchip_send_msi() to send  msi to kernel.

Signed-off-by: Song Gao <[email protected]>
Reviewed-by: Bibo Mao <[email protected]>
---
 hw/intc/loongarch_dintc.c         | 13 +++++++++
 hw/intc/loongarch_dintc_kvm.c     | 48 +++++++++++++++++++++++++++++++
 hw/intc/meson.build               |  2 ++
 include/hw/intc/loongarch_dintc.h | 10 +++++++
 4 files changed, 73 insertions(+)
 create mode 100644 hw/intc/loongarch_dintc_kvm.c

diff --git a/hw/intc/loongarch_dintc.c b/hw/intc/loongarch_dintc.c
index e40292887c..94d418261c 100644
--- a/hw/intc/loongarch_dintc.c
+++ b/hw/intc/loongarch_dintc.c
@@ -68,6 +68,15 @@ static void loongarch_dintc_mem_write(void *opaque, hwaddr addr,
     }
     irq_num = FIELD_EX64(msg_addr, MSG_ADDR, IRQ_NUM);
 
+    if (kvm_irqchip_in_kernel()) {
+        MSIMessage msg;
+
+        msg.address = msg_addr;
+        msg.data = val;
+        kvm_irqchip_send_msi(kvm_state, msg);
+        return;
+    }
+
     async_run_on_cpu(cs, do_set_vcpu_dintc_irq,
                          RUN_ON_CPU_HOST_INT(irq_num));
     qemu_set_irq(s->cpu[cpu_num].parent_irq, 1);
@@ -110,6 +119,10 @@ static void loongarch_dintc_realize(DeviceState *dev, Error **errp)
         qdev_init_gpio_out(dev, &s->cpu[i].parent_irq, 1);
     }
 
+    if (kvm_irqchip_in_kernel()) {
+        kvm_dintc_realize(dev, errp);
+    }
+
     return;
 }
 
diff --git a/hw/intc/loongarch_dintc_kvm.c b/hw/intc/loongarch_dintc_kvm.c
new file mode 100644
index 0000000000..1137bcd9a6
--- /dev/null
+++ b/hw/intc/loongarch_dintc_kvm.c
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * LoongArch DINTC interrupt kvm support
+ *
+ * Copyright (C) 2025 Loongson Technology Corporation Limited
+ */
+
+#include "qemu/osdep.h"
+#include "hw/intc/loongarch_dintc.h"
+#include "linux/kvm.h"
+#include "qapi/error.h"
+#include "system/kvm.h"
+
+void kvm_dintc_realize(DeviceState *dev, Error **errp)
+{
+    LoongArchDINTCState *lds = LOONGARCH_DINTC(dev);
+    int ret;
+
+    ret = kvm_create_device(kvm_state, KVM_DEV_TYPE_LOONGARCH_DMSINTC, false);
+    if (ret < 0) {
+        fprintf(stderr, "create KVM_DEV_TYPE_LOONGARCH_AVEC failed: %s\n",
+               strerror(-ret));
+        abort();
+    }
+    lds->dev_fd = ret;
+
+    /* init dintc config */
+    lds->msg_addr_base = VIRT_DINTC_BASE;
+    lds->msg_addr_size = VIRT_DINTC_SIZE;
+
+    ret = kvm_device_access(lds->dev_fd, KVM_DEV_LOONGARCH_DMSINTC_GRP_CTRL,
+                            KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE,
+                            &lds->msg_addr_base, true, NULL);
+    if (ret < 0) {
+        fprintf(stderr, "KVM_DEV_LOONGARCH_DINTC_MSG_ADDR_BASE failed: %s\n",
+                strerror(ret));
+        abort();
+    }
+
+    ret = kvm_device_access(lds->dev_fd, KVM_DEV_LOONGARCH_DMSINTC_GRP_CTRL,
+                            KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE,
+                            &lds->msg_addr_size, true, NULL);
+    if (ret < 0) {
+        fprintf(stderr, "KVM_DEV_LOONGARCH_DINTC_MSG_ADDR_SIZE failed: %s\n",
+                strerror(ret));
+        abort();
+    }
+}
diff --git a/hw/intc/meson.build b/hw/intc/meson.build
index a1401cb521..4373f16d0b 100644
--- a/hw/intc/meson.build
+++ b/hw/intc/meson.build
@@ -90,3 +90,5 @@ specific_ss.add(when: 'CONFIG_LOONGARCH_EXTIOI', if_true: files('loongarch_extio
 specific_ss.add(when: ['CONFIG_KVM', 'CONFIG_LOONGARCH_EXTIOI'],
                if_true: files('loongarch_extioi_kvm.c'))
 specific_ss.add(when: 'CONFIG_LOONGARCH_DINTC', if_true: files('loongarch_dintc.c'))
+specific_ss.add(when: ['CONFIG_KVM', 'CONFIG_LOONGARCH_DINTC'],
+               if_true: files('loongarch_dintc_kvm.c'))
diff --git a/include/hw/intc/loongarch_dintc.h b/include/hw/intc/loongarch_dintc.h
index 1f4f65705a..95a7879e26 100644
--- a/include/hw/intc/loongarch_dintc.h
+++ b/include/hw/intc/loongarch_dintc.h
@@ -9,8 +9,13 @@
 #include "hw/core/sysbus.h"
 #include "hw/loongarch/virt.h"
 #include "system/memory.h"
+#include "hw/pci-host/ls7a.h"
 
 #define NR_VECTORS     256
+#define IRQ_BIT_BASE    5
+#define IRQ_BIT_LEN     8
+#define CPU_BIT_BASE   13
+#define CPU_BIT_LEN     8
 
 #define TYPE_LOONGARCH_DINTC "loongarch_dintc"
 OBJECT_DECLARE_TYPE(LoongArchDINTCState, LoongArchDINTCClass, LOONGARCH_DINTC)
@@ -25,7 +30,10 @@ struct LoongArchDINTCState {
     SysBusDevice parent_obj;
     MemoryRegion dintc_mmio;
     DINTCCore *cpu;
+    int dev_fd;
     uint32_t num_cpu;
+    uint64_t msg_addr_base;
+    uint64_t msg_addr_size;
 };
 
 struct LoongArchDINTCClass {
@@ -34,3 +42,5 @@ struct LoongArchDINTCClass {
     DeviceRealize parent_realize;
     DeviceUnrealize parent_unrealize;
 };
+
+void kvm_dintc_realize(DeviceState *dev, Error **errp);
-- 
2.47.3