riscv: sifive_u: Add support for loading initrd

Add support for loading initrd with "-initrd <filename>"
to the sifive_u machine. This lets us boot into Linux without
disk drive.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index 9910fa670823ed52bda13e3882da4261e7cc1d6d..32167d05a10b9142cf1401561433a19c77d16d92 100644 (file)
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -67,7 +67,7 @@ static const struct MemmapEntry {
 
 #define GEM_REVISION        0x10070109
 
-static void create_fdt(SiFiveUState *s, const struct MemmapEntry *memmap,
+static void *create_fdt(SiFiveUState *s, const struct MemmapEntry *memmap,
     uint64_t mem_size, const char *cmdline)
 {
     void *fdt;
@@ -244,11 +244,14 @@ static void create_fdt(SiFiveUState *s, const struct MemmapEntry *memmap,
         qemu_fdt_setprop_string(fdt, "/chosen", "bootargs", cmdline);
     }
     g_free(nodename);
+
+    return fdt;
 }
 
 static void riscv_sifive_u_init(MachineState *machine)
 {
     const struct MemmapEntry *memmap = sifive_u_memmap;
+    void *fdt;
 
     SiFiveUState *s = g_new0(SiFiveUState, 1);
     MemoryRegion *system_memory = get_system_memory();
@@ -269,13 +272,24 @@ static void riscv_sifive_u_init(MachineState *machine)
                                 main_mem);
 
     /* create device tree */
-    create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
+    fdt = create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
 
     riscv_find_and_load_firmware(machine, BIOS_FILENAME,
                                  memmap[SIFIVE_U_DRAM].base);
 
     if (machine->kernel_filename) {
-        riscv_load_kernel(machine->kernel_filename);
+        uint64_t kernel_entry = riscv_load_kernel(machine->kernel_filename);
+
+        if (machine->initrd_filename) {
+            hwaddr start;
+            hwaddr end = riscv_load_initrd(machine->initrd_filename,
+                                           machine->ram_size, kernel_entry,
+                                           &start);
+            qemu_fdt_setprop_cell(fdt, "/chosen",
+                                  "linux,initrd-start", start);
+            qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-end",
+                                  end);
+        }
     }
 
     /* reset vector */