Implement virtio-gpu device

Author: shengwen-tw

Makefile

@@ -4,6 +4,7 @@ include mk/check-libs.mk
 CC ?= gcc
 CFLAGS := -O2 -g -Wall -Wextra
 CFLAGS += -include common.h
+LDFLAGS :=
 
 # clock frequency
 CLOCK_FREQ ?= 65000000
@@ -14,7 +15,7 @@ OBJS_EXTRA :=
 # command line option
 OPTS :=
 
-LDFLAGS :=
+LDFLAGS := -lm -lpthread
 
 # virtio-blk
 ENABLE_VIRTIOBLK ?= 1
@@ -115,6 +116,33 @@ LDFLAGS += -lm
 # after git submodule.
 .DEFAULT_GOAL := all
 
+# virtio-gpu
+ENABLE_VIRTIOGPU ?= 1
+ifneq ($(UNAME_S),Linux)
+    ENABLE_VIRTIOGPU := 0
+endif
+
+# SDL2
+ENABLE_SDL ?= 1
+ifeq (, $(shell which sdl2-config))
+    $(warning No sdl2-config in $$PATH. Check SDL2 installation in advance)
+    override ENABLE_SDL := 0
+endif
+
+ifeq ($(ENABLE_SDL),1)
+    CFLAGS += $(shell sdl2-config --cflags)
+    LDFLAGS += $(shell sdl2-config --libs)
+else
+    override ENABLE_VIRTIOGPU := 0
+endif
+
+ifeq ($(ENABLE_VIRTIOGPU),1)
+    OBJS_EXTRA += window.o
+    OBJS_EXTRA += virtio-gpu.o
+endif
+
+$(call set-feature, VIRTIOGPU)
+
 BIN = semu
 all: $(BIN) minimal.dtb
 

device.h

@@ -222,6 +222,59 @@ void virtio_rng_write(hart_t *vm,
 void virtio_rng_init(void);
 #endif /* SEMU_HAS(VIRTIORNG) */
 
+/* VirtIO-GPU */
+
+#if SEMU_HAS(VIRTIOGPU)
+
+#define IRQ_VGPU 6
+#define IRQ_VGPU_BIT (1 << IRQ_VGPU)
+
+typedef struct {
+    uint32_t QueueNum;
+    uint32_t QueueDesc;
+    uint32_t QueueAvail;
+    uint32_t QueueUsed;
+    uint16_t last_avail;
+    bool ready;
+} virtio_gpu_queue_t;
+
+typedef struct {
+    /* feature negotiation */
+    uint32_t DeviceFeaturesSel;
+    uint32_t DriverFeatures;
+    uint32_t DriverFeaturesSel;
+    /* queue config */
+    uint32_t QueueSel;
+    virtio_gpu_queue_t queues[2];
+    /* status */
+    uint32_t Status;
+    uint32_t InterruptStatus;
+    /* supplied by environment */
+    uint32_t *ram;
+    /* implementation-specific */
+    void *priv;
+} virtio_gpu_state_t;
+
+void virtio_gpu_read(hart_t *vm,
+                     virtio_gpu_state_t *vgpu,
+                     uint32_t addr,
+                     uint8_t width,
+                     uint32_t *value);
+
+void virtio_gpu_write(hart_t *vm,
+                      virtio_gpu_state_t *vgpu,
+                      uint32_t addr,
+                      uint8_t width,
+                      uint32_t value);
+
+void semu_virgl_init(virtio_gpu_state_t *vgpu);
+
+void virtio_gpu_init(virtio_gpu_state_t *vgpu);
+void virtio_gpu_add_scanout(virtio_gpu_state_t *vgpu,
+                            uint32_t width,
+                            uint32_t height);
+#endif /* SEMU_HAS(VIRTIOGPU) */
+
 /* ACLINT MTIMER */
 typedef struct {
     /* A MTIMER device has two separate base addresses: one for the MTIME
@@ -374,6 +427,9 @@ typedef struct {
 #endif
 #if SEMU_HAS(VIRTIORNG)
     virtio_rng_state_t vrng;
+#endif
+#if SEMU_HAS(VIRTIOGPU)
+    virtio_gpu_state_t vgpu;
 #endif
     /* ACLINT */
     mtimer_state_t mtimer;

feature.h

@@ -17,5 +17,10 @@
 #define SEMU_FEATURE_VIRTIOSND 1
 #endif
 
+/* virtio-gpu */
+#ifndef SEMU_FEATURE_VIRTIOGPU
+#define SEMU_FEATURE_VIRTIOGPU 1
+#endif
+
 /* Feature test macro */
 #define SEMU_HAS(x) SEMU_FEATURE_##x

main.c

@@ -13,6 +13,8 @@
 #include "mini-gdbstub/include/gdbstub.h"
 #include "riscv.h"
 #include "riscv_private.h"
+#include "window.h"
+
 #define PRIV(x) ((emu_state_t *) x->priv)
 
 /* Define fetch separately since it is simpler (fixed width, already checked
@@ -85,6 +87,18 @@ static void emu_update_vrng_interrupts(vm_t *vm)
 }
 #endif
 
+#if SEMU_HAS(VIRTIOGPU)
+static void emu_update_vgpu_interrupts(vm_t *vm)
+{
+    emu_state_t *data = PRIV(vm->hart[0]);
+    if (data->vgpu.InterruptStatus)
+        data->plic.active |= IRQ_VGPU_BIT;
+    else
+        data->plic.active &= ~IRQ_VGPU_BIT;
+    plic_update_interrupts(vm, &data->plic);
+}
+#endif
+
 static void emu_update_timer_interrupt(hart_t *hart)
 {
     emu_state_t *data = PRIV(hart);
@@ -168,12 +182,17 @@ static void mem_load(hart_t *hart,
             emu_update_vrng_interrupts(hart->vm);
             return;
 #endif
-
 #if SEMU_HAS(VIRTIOSND)
         case 0x47: /* virtio-snd */
             virtio_snd_read(hart, &data->vsnd, addr & 0xFFFFF, width, value);
             emu_update_vsnd_interrupts(hart->vm);
             return;
+#endif
+#if SEMU_HAS(VIRTIOGPU)
+        case 0x48: /* virtio-gpu */
+            virtio_gpu_read(hart, &data->vgpu, addr & 0xFFFFF, width, value);
+            emu_update_vgpu_interrupts(hart->vm);
+            return;
 #endif
         }
     }
@@ -229,19 +248,23 @@ static void mem_store(hart_t *hart,
             aclint_sswi_write(hart, &data->sswi, addr & 0xFFFFF, width, value);
             aclint_sswi_update_interrupts(hart, &data->sswi);
             return;
-
 #if SEMU_HAS(VIRTIORNG)
         case 0x46: /* virtio-rng */
             virtio_rng_write(hart, &data->vrng, addr & 0xFFFFF, width, value);
             emu_update_vrng_interrupts(hart->vm);
             return;
 #endif
-
 #if SEMU_HAS(VIRTIOSND)
         case 0x47: /* virtio-snd */
             virtio_snd_write(hart, &data->vsnd, addr & 0xFFFFF, width, value);
             emu_update_vsnd_interrupts(hart->vm);
             return;
+#endif
+#if SEMU_HAS(VIRTIOGPU)
+        case 0x48: /* virtio-gpu */
+            virtio_gpu_write(hart, &data->vgpu, addr & 0xFFFFF, width, value);
+            emu_update_vgpu_interrupts(hart->vm);
+            return;
 #endif
         }
     }
@@ -691,6 +714,12 @@ static int semu_init(emu_state_t *emu, int argc, char **argv)
         fprintf(stderr, "No virtio-snd functioned\n");
     emu->vsnd.ram = emu->ram;
 #endif
+#if SEMU_HAS(VIRTIOGPU)
+    emu->vgpu.ram = emu->ram;
+    virtio_gpu_init(&(emu->vgpu));
+    virtio_gpu_add_scanout(&(emu->vgpu), 1024, 768);
+    window_init();
+#endif
 
     emu->peripheral_update_ctr = 0;
     emu->debug = debug;
@@ -728,6 +757,11 @@ static int semu_step(emu_state_t *emu)
             if (emu->vsnd.InterruptStatus)
                 emu_update_vsnd_interrupts(vm);
 #endif
+
+#if SEMU_HAS(VIRTIOGPU)
+            if (emu->vgpu.InterruptStatus)
+                emu_update_vgpu_interrupts(vm);
+#endif
         }
 
         emu_update_timer_interrupt(vm->hart[i]);

minimal.dts

@@ -79,5 +79,13 @@
             interrupts = <5>;
         };
 #endif
+
+#if SEMU_FEATURE_VIRTIOGPU 
+        gpu0: virtio@4800000 {
+            compatible = "virtio,mmio";
+            reg = <0x4800000 0x200>;
+            interrupts = <6>;
+        };       
+#endif
     };
 };

utils.h

@@ -79,6 +79,13 @@ static inline void list_del_init(struct list_head *node)
     INIT_LIST_HEAD(node);
 }
 
+#define LIST_HEAD_INIT(name)             \
+    {                                    \
+        .prev = (&name), .next = (&name) \
+    }
+
+#define LIST_HEAD(name) struct list_head name = LIST_HEAD_INIT(name)
+
 #ifndef container_of
 #define container_of(ptr, type, member)                            \
     __extension__({                                                \
@@ -87,7 +94,7 @@ static inline void list_del_init(struct list_head *node)
     })
 #else
 #define container_of(ptr, type, member) \
-    ((type *) ((char *) (ptr) - offsetof(type, member)))
+    ((type *) ((char *) (ptr) -offsetof(type, member)))
 #endif
 
 #define list_entry(node, type, member) container_of(node, type, member)