hw/riscv: write initrd 'chosen' FDT inside riscv_load_initrd()

riscv_load_initrd() returns the initrd end addr while also writing a
'start' var to mark the addr start. These informations are being used
just to write the initrd FDT node. Every existing caller of
riscv_load_initrd() is writing the FDT in the same manner.

We can simplify things by writing the FDT inside riscv_load_initrd(),
sparing callers from having to manage start/end addrs to write the FDT
themselves.

An 'if (fdt)' check is already inserted at the end of the function
because we'll end up using it later on with other boards that doesn´t
have a FDT.

Cc: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230102115241.25733-7-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 12 insertions, 6 deletions

diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c
index 31aa338..6b948d1 100644
--- a/hw/riscv/boot.c
+++ b/hw/riscv/boot.c
@@ -208,9 +208,10 @@ target_ulong riscv_load_kernel(const char *kernel_filename,
     exit(1);
 }
 
-hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
-                         uint64_t kernel_entry, hwaddr *start)
+void riscv_load_initrd(const char *filename, uint64_t mem_size,
+                       uint64_t kernel_entry, void *fdt)
 {
+    hwaddr start, end;
     ssize_t size;
 
     g_assert(filename != NULL);
@@ -226,18 +227,23 @@ hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
      * halfway into RAM, and for boards with 256MB of RAM or more we put
      * the initrd at 128MB.
      */
-    *start = kernel_entry + MIN(mem_size / 2, 128 * MiB);
+    start = kernel_entry + MIN(mem_size / 2, 128 * MiB);
 
-    size = load_ramdisk(filename, *start, mem_size - *start);
+    size = load_ramdisk(filename, start, mem_size - start);
     if (size == -1) {
-        size = load_image_targphys(filename, *start, mem_size - *start);
+        size = load_image_targphys(filename, start, mem_size - start);
         if (size == -1) {
             error_report("could not load ramdisk '%s'", filename);
             exit(1);
         }
     }
 
-    return *start + size;
+    /* Some RISC-V machines (e.g. opentitan) don't have a fdt. */
+    if (fdt) {
+        end = start + size;
+        qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-start", start);
+        qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-end", end);
+    }
 }
 
 uint64_t riscv_load_fdt(hwaddr dram_base, uint64_t mem_size, void *fdt)