fw_loader: Split from fs_loader into separate library file

The script based firmware loader does not use anything from the
fs_loader implementation. Separate it into its own library source
file and convert the mediatek PHY to use this separate code. This
should reduce the amount of code that is pulled in alongside the
firmware loader, as the FS loader is no longer included.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>

1 files changed, 57 insertions, 0 deletions

diff --git a/lib/fw_loader.c b/lib/fw_loader.c
new file mode 100644
index 00000000000..207f5fadd1e
--- /dev/null
+++ b/lib/fw_loader.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2025 Lucien Jheng <lucienzx159@gmail.com>
+ */
+
+#include <command.h>
+#include <env.h>
+#include <errno.h>
+#include <linux/types.h>
+#include <log.h>
+
+int request_firmware_into_buf_via_script(void *buf, size_t max_size,
+					 const char *script_name,
+					 size_t *retsize)
+{
+	char *args[2] = { "run", (char *)script_name };
+	int ret, repeatable;
+	ulong addr, size;
+
+	if (!buf || !script_name || !max_size)
+		return -EINVAL;
+
+	/* Run the firmware loading script */
+	ret = cmd_process(0, 2, args, &repeatable, NULL);
+	if (ret) {
+		log_err("Firmware loading script '%s' not defined or failed.\n",
+			script_name);
+		return -EINVAL;
+	}
+
+	/* Find out where the firmware got loaded and how long it is */
+	addr = env_get_hex("fw_addr", 0);
+	size = env_get_hex("fw_size", 0);
+
+	/* Clear the variables set by the firmware loading script */
+	env_set("fw_addr", NULL);
+	env_set("fw_size", NULL);
+
+	if (!addr || !size) {
+		log_err("Firmware address (0x%lx) or size (0x%lx) are invalid.\n",
+			addr, size);
+		return -EINVAL;
+	}
+
+	if (size > max_size) {
+		log_err("Loaded firmware size 0x%lx exceeded maximum allowed size 0x%zx.\n",
+			size, max_size);
+		return -E2BIG;
+	}
+
+	if (retsize)
+		*retsize = size;
+
+	memcpy(buf, (void *)addr, size);
+
+	return 0;
+}