diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c
index 12f9792245..09878e722c 100644
--- a/hw/riscv/boot.c
+++ b/hw/riscv/boot.c
@@ -189,13 +189,13 @@ static void riscv_load_initrd(MachineState *machine, uint64_t kernel_entry)
      * kernel is uncompressed it will not clobber the initrd. However
      * on boards without much RAM we must ensure that we still leave
      * enough room for a decent sized initrd, and on boards with large
-     * amounts of RAM we must avoid the initrd being so far up in RAM
-     * that it is outside lowmem and inaccessible to the kernel.
-     * So for boards with less  than 256MB of RAM we put the initrd
-     * halfway into RAM, and for boards with 256MB of RAM or more we put
-     * the initrd at 128MB.
+     * amounts of RAM, we put the initrd at 512MB to allow large kernels
+     * to boot.
+     * So for boards with less than 1GB of RAM we put the initrd
+     * halfway into RAM, and for boards with 1GB of RAM or more we put
+     * the initrd at 512MB.
      */
-    start = kernel_entry + MIN(mem_size / 2, 128 * MiB);
+    start = kernel_entry + MIN(mem_size / 2, 512 * MiB);
 
     size = load_ramdisk(filename, start, mem_size - start);
     if (size == -1) {