[WIP] Implement virtio-pci transport layer

Author: shengwen-tw

Makefile

@@ -16,6 +16,13 @@ OPTS :=
 
 LDFLAGS :=
 
+# virtio-pci
+ENABLE_VIRTIOPCI ?= 1
+$(call set-feature, VIRTIOPCI)
+ifeq ($(call has, VIRTIOPCI), 1)
+    OBJS_EXTRA += virtio-pci.o
+endif
+
 # virtio-blk
 ENABLE_VIRTIOBLK ?= 1
 $(call set-feature, VIRTIOBLK)

device.h

@@ -76,6 +76,27 @@ void u8250_write(hart_t *core,
 void u8250_check_ready(u8250_state_t *uart);
 void capture_keyboard_input();
 
+/* virtio-pci */
+#if SEMU_HAS(VIRTIOPCI)
+typedef struct {
+    void *priv;
+} virtio_pci_state_t;
+
+void virtio_pci_read(hart_t *vm,
+                     virtio_pci_state_t *vpci,
+                     uint32_t addr,
+                     uint8_t width,
+                     uint32_t *value);
+
+void virtio_pci_write(hart_t *vm,
+                      virtio_pci_state_t *vpci,
+                      uint32_t addr,
+                      uint8_t width,
+                      uint32_t value);
+
+void virtio_pci_init(virtio_pci_state_t *vpci);
+#endif /* SEMU_HAS(VIRTIOPCI) */
+
 /* virtio-net */
 
 #if SEMU_HAS(VIRTIONET)
@@ -366,6 +387,9 @@ typedef struct {
     vm_t vm;
     plic_state_t plic;
     u8250_state_t uart;
+#if SEMU_HAS(VIRTIOPCI)
+    virtio_pci_state_t vpci;
+#endif
 #if SEMU_HAS(VIRTIONET)
     virtio_net_state_t vnet;
 #endif

main.c

@@ -125,7 +125,10 @@ static void mem_load(hart_t *hart,
         return;
     }
 
-    if ((addr >> 28) == 0xF) { /* MMIO at 0xF_______ */
+    if ((addr >> 28) == 0x2) { /* MMIO at 0x2_______ */
+        virtio_pci_read(hart, &data->vsnd, addr, width, value);
+        return;
+    } else if ((addr >> 28) == 0xF) { /* MMIO at 0xF_______ */
         /* 256 regions of 1MiB */
         switch ((addr >> 20) & MASK(8)) {
         case 0x0:
@@ -192,7 +195,15 @@ static void mem_store(hart_t *hart,
         return;
     }
 
-    if ((addr >> 28) == 0xF) { /* MMIO at 0xF_______ */
+    /* TODO */
+    if (addr >= 0x100000 && addr <= 0x200000) {
+        printf("!!!!!!!!!!!!!!!!!\n\n\n\n\n");
+    }
+
+    if ((addr >> 28) == 0x2) { /* MMIO at 0x2_______ */
+        virtio_pci_write(hart, &data->vsnd, addr, width, value);
+        return;
+    } else if ((addr >> 28) == 0xF) { /* MMIO at 0xF_______ */
         /* 256 regions of 1MiB */
         switch ((addr >> 20) & MASK(8)) {
         case 0x0:
@@ -668,6 +679,9 @@ static int semu_init(emu_state_t *emu, int argc, char **argv)
     /* Set up peripherals */
     emu->uart.in_fd = 0, emu->uart.out_fd = 1;
     capture_keyboard_input(); /* set up uart */
+#if SEMU_HAS(VIRTIOPCI)
+    virtio_pci_init(&(emu->vpci));
+#endif
 #if SEMU_HAS(VIRTIONET)
     if (!virtio_net_init(&(emu->vnet), netdev))
         fprintf(stderr, "No virtio-net functioned\n");

minimal.dts

@@ -33,6 +33,21 @@
         reg-names = "sram0";
     };
 
+#if SEMU_FEATURE_VIRTIOPCI
+    pci0: pci@21000000 {
+        compatible = "pci-host-ecam-generic";
+        device_type = "pci";
+        #address-cells = <3>;
+        #size-cells = <2>;
+        bus-range = <0x0 0x0>; /* Use 1 bus only */
+        reg = <0x21000000 0x100000>;
+
+        /* Reserve memory for BAR mapping */
+        ranges = <0x02000000 0 0x100000   /* PCI memory space (BAR) */
+                  0x20000000 0 0x100000>; /* CPU address space, 16MB */
+    };
+#endif
+
     soc: soc@F0000000 {
         #address-cells = <1>;
         #size-cells = <1>;

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__({                                                \