hw/riscv: Move the dtb load bits outside of create_fdt()

Move the dtb load bits outside of create_fdt(), and put it explicitly
in sifive_u_machine_init() and virt_machine_init(). With such change
create_fdt() does exactly what its function name tells us.

Suggested-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20230228074522.1845007-2-bmeng@tinylab.org>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

hw/riscv/sifive_u.c

@@ -99,7 +99,7 @@ static void create_fdt(SiFiveUState *s, const MemMapEntry *memmap,
     MachineState *ms = MACHINE(s);
     uint64_t mem_size = ms->ram_size;
     void *fdt;
-    int cpu, fdt_size;
+    int cpu;
     uint32_t *cells;
     char *nodename;
     uint32_t plic_phandle, prci_phandle, gpio_phandle, phandle = 1;
@@ -112,19 +112,10 @@ static void create_fdt(SiFiveUState *s, const MemMapEntry *memmap,
         "sifive,plic-1.0.0", "riscv,plic0"
     };
 
-    if (ms->dtb) {
-        fdt = ms->fdt = load_device_tree(ms->dtb, &fdt_size);
-        if (!fdt) {
-            error_report("load_device_tree() failed");
-            exit(1);
-        }
-        return;
-    } else {
-        fdt = ms->fdt = create_device_tree(&fdt_size);
-        if (!fdt) {
-            error_report("create_device_tree() failed");
-            exit(1);
-        }
+    fdt = ms->fdt = create_device_tree(&s->fdt_size);
+    if (!fdt) {
+        error_report("create_device_tree() failed");
+        exit(1);
     }
 
     qemu_fdt_setprop_string(fdt, "/", "model", "SiFive HiFive Unleashed A00");
@@ -561,8 +552,16 @@ static void sifive_u_machine_init(MachineState *machine)
     qdev_connect_gpio_out(DEVICE(&(s->soc.gpio)), 10,
                           qemu_allocate_irq(sifive_u_machine_reset, NULL, 0));
 
-    /* create device tree */
-    create_fdt(s, memmap, riscv_is_32bit(&s->soc.u_cpus));
+    /* load/create device tree */
+    if (machine->dtb) {
+        machine->fdt = load_device_tree(machine->dtb, &s->fdt_size);
+        if (!machine->fdt) {
+            error_report("load_device_tree() failed");
+            exit(1);
+        }
+    } else {
+        create_fdt(s, memmap, riscv_is_32bit(&s->soc.u_cpus));
+    }
 
     if (s->start_in_flash) {
         /*

hw/riscv/virt.c

@@ -1009,19 +1009,10 @@ static void create_fdt(RISCVVirtState *s, const MemMapEntry *memmap)
     uint32_t irq_pcie_phandle = 1, irq_virtio_phandle = 1;
     uint8_t rng_seed[32];
 
-    if (ms->dtb) {
-        ms->fdt = load_device_tree(ms->dtb, &s->fdt_size);
-        if (!ms->fdt) {
-            error_report("load_device_tree() failed");
-            exit(1);
-        }
-        return;
-    } else {
-        ms->fdt = create_device_tree(&s->fdt_size);
-        if (!ms->fdt) {
-            error_report("create_device_tree() failed");
-            exit(1);
-        }
+    ms->fdt = create_device_tree(&s->fdt_size);
+    if (!ms->fdt) {
+        error_report("create_device_tree() failed");
+        exit(1);
     }
 
     qemu_fdt_setprop_string(ms->fdt, "/", "model", "riscv-virtio,qemu");
@@ -1506,8 +1497,16 @@ static void virt_machine_init(MachineState *machine)
     }
     virt_flash_map(s, system_memory);
 
-    /* create device tree */
-    create_fdt(s, memmap);
+    /* load/create device tree */
+    if (machine->dtb) {
+        machine->fdt = load_device_tree(machine->dtb, &s->fdt_size);
+        if (!machine->fdt) {
+            error_report("load_device_tree() failed");
+            exit(1);
+        }
+    } else {
+        create_fdt(s, memmap);
+    }
 
     s->machine_done.notify = virt_machine_done;
     qemu_add_machine_init_done_notifier(&s->machine_done);

include/hw/riscv/sifive_u.h

@@ -68,6 +68,7 @@ typedef struct SiFiveUState {
 
     /*< public >*/
     SiFiveUSoCState soc;
+    int fdt_size;
 
     bool start_in_flash;
     uint32_t msel;