hw/riscv: Split out the boot functions

Split the common RISC-V boot functions into a seperate file. This allows
us to share the common code.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

1 files changed, 69 insertions, 0 deletions

diff --git a/hw/riscv/boot.c b/hw/riscv/boot.c
new file mode 100644
index 0000000..0c8e72e
--- /dev/null
+++ b/hw/riscv/boot.c
@@ -0,0 +1,69 @@
+/*
+ * QEMU RISC-V Boot Helper
+ *
+ * Copyright (c) 2017 SiFive, Inc.
+ * Copyright (c) 2019 Alistair Francis <alistair.francis@wdc.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/units.h"
+#include "qemu/error-report.h"
+#include "exec/cpu-defs.h"
+#include "hw/loader.h"
+#include "hw/riscv/boot.h"
+#include "elf.h"
+
+target_ulong riscv_load_kernel(const char *kernel_filename)
+{
+    uint64_t kernel_entry, kernel_high;
+
+    if (load_elf(kernel_filename, NULL, NULL, NULL,
+                 &kernel_entry, NULL, &kernel_high, 0, EM_RISCV, 1, 0) < 0) {
+        error_report("could not load kernel '%s'", kernel_filename);
+        exit(1);
+    }
+
+    return kernel_entry;
+}
+
+hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
+                         uint64_t kernel_entry, hwaddr *start)
+{
+    int size;
+
+    /*
+     * We want to put the initrd far enough into RAM that when the
+     * 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.
+     */
+    *start = kernel_entry + MIN(mem_size / 2, 128 * MiB);
+
+    size = load_ramdisk(filename, *start, mem_size - *start);
+    if (size == -1) {
+        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;
+}