hw/loongarch: add virt feature dmsi support

dmsi feature is added in LoongArchVirtMachinState, and it is used
to check whether virt machine supports the directy Message-Interrupts.
and by default set dmsi with ON_OFF_AUTO_AUTO.
LoongArchVirtMachineState adds misc_feature and misc_status for misc
features and status. and set the default dintc feature bit.
Msgint feature is added in LoongArchCPU, and it is used to check
whether th cpu supports the Message-Interrupts and by default set
mesgint with ON_OFF_AUTO_AUTO.

Signed-off-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Message-ID: <20250916122109.749813-3-gaosong@loongson.cn>

1 files changed, 50 insertions, 0 deletions

diff --git a/hw/loongarch/virt.c b/hw/loongarch/virt.c
index bd5cff1f1e..256af63d73 100644
--- a/hw/loongarch/virt.c
+++ b/hw/loongarch/virt.c
@@ -48,6 +48,30 @@
 #include "qemu/error-report.h"
 #include "kvm/kvm_loongarch.h"
 
+static void virt_get_dmsi(Object *obj, Visitor *v, const char *name,
+                             void *opaque, Error **errp)
+{
+    LoongArchVirtMachineState *lvms = LOONGARCH_VIRT_MACHINE(obj);
+    OnOffAuto dmsi = lvms->dmsi;
+
+    visit_type_OnOffAuto(v, name, &dmsi, errp);
+
+}
+static void virt_set_dmsi(Object *obj, Visitor *v, const char *name,
+                              void *opaque, Error **errp)
+{
+    LoongArchVirtMachineState *lvms = LOONGARCH_VIRT_MACHINE(obj);
+
+    visit_type_OnOffAuto(v, name, &lvms->dmsi, errp);
+
+    if (lvms->dmsi == ON_OFF_AUTO_OFF) {
+        lvms->misc_feature &= ~BIT(IOCSRF_DMSI);
+        lvms->misc_status &= ~BIT_ULL(IOCSRM_DMSI_EN);
+    } else if (lvms->dmsi == ON_OFF_AUTO_ON) {
+        lvms->misc_feature = BIT(IOCSRF_DMSI);
+    }
+}
+
 static void virt_get_veiointc(Object *obj, Visitor *v, const char *name,
                               void *opaque, Error **errp)
 {
@@ -683,6 +707,25 @@ static void fw_cfg_add_memory(MachineState *ms)
     }
 }
 
+static void virt_check_dmsi(MachineState *machine)
+{
+    LoongArchCPU *cpu;
+    LoongArchVirtMachineState *lvms = LOONGARCH_VIRT_MACHINE(machine);
+
+    cpu = LOONGARCH_CPU(first_cpu);
+    if (lvms->dmsi == ON_OFF_AUTO_AUTO) {
+        if (cpu->msgint != ON_OFF_AUTO_OFF) {
+            lvms->misc_feature = BIT(IOCSRF_DMSI);
+        }
+    }
+
+    if (lvms->dmsi == ON_OFF_AUTO_ON && cpu->msgint == ON_OFF_AUTO_OFF) {
+        error_report("Fail to enable dmsi , cpu msgint is off "
+                     "pleass add cpu feature mesgint=on.");
+        exit(EXIT_FAILURE);
+    }
+}
+
 static void virt_init(MachineState *machine)
 {
     const char *cpu_model = machine->cpu_type;
@@ -717,6 +760,7 @@ static void virt_init(MachineState *machine)
         }
         qdev_realize_and_unref(DEVICE(cpuobj), NULL, &error_fatal);
     }
+    virt_check_dmsi(machine);
     fw_cfg_add_memory(machine);
 
     /* Node0 memory */
@@ -847,6 +891,8 @@ static void virt_initfn(Object *obj)
     if (tcg_enabled()) {
         lvms->veiointc = ON_OFF_AUTO_OFF;
     }
+
+    lvms->dmsi = ON_OFF_AUTO_AUTO;
     lvms->acpi = ON_OFF_AUTO_AUTO;
     lvms->oem_id = g_strndup(ACPI_BUILD_APPNAME6, 6);
     lvms->oem_table_id = g_strndup(ACPI_BUILD_APPNAME8, 8);
@@ -1241,6 +1287,10 @@ static void virt_class_init(ObjectClass *oc, const void *data)
         NULL, NULL);
     object_class_property_set_description(oc, "v-eiointc",
                             "Enable Virt Extend I/O Interrupt Controller.");
+    object_class_property_add(oc, "dmsi", "OnOffAuto",
+        virt_get_dmsi, virt_set_dmsi, NULL, NULL);
+    object_class_property_set_description(oc, "dmsi",
+                            "Enable direct Message-interrupts Controller.");
     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_RAMFB_DEVICE);
     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_UEFI_VARS_SYSBUS);
 #ifdef CONFIG_TPM