This commit adds request_firmware_into_buf_via_env() to the fs_loader driver,
enabling firmware loading into a buffer
using environment variables for path and size.
It supports multiple entries via indexed variable names
(e.g., "fw_dir0", "fw_size0").
This provides flexible, scriptable firmware loading without hardcoded details.
Signed-off-by: Lucien.Jheng <lucienzx...@gmail.com>
---
Change log:
- Re-sending as previous version and add more maintainers to review.
drivers/misc/fs_loader.c | 59 ++++++++++++++++++++++++++++++++++++++++
include/fs_loader.h | 18 ++++++++++++
2 files changed, 77 insertions(+)
diff --git a/drivers/misc/fs_loader.c b/drivers/misc/fs_loader.c
index 66803f4b997..a4f4448f5cc 100644
--- a/drivers/misc/fs_loader.c
+++ b/drivers/misc/fs_loader.c
@@ -228,6 +228,65 @@ int request_firmware_into_buf(struct udevice *dev,
return ret;
}
+/**
+ * request_firmware_into_buf_via_env - Load firmware using environment
variables.
+ * @dev: An instance of a driver.
+ * @buf: Address of buffer to load firmware into.
+ * @offset: Offset of a file for start reading into buffer.
+ * @fw_index: Index of the firmware entry to load.
+ *
+ * This function loads firmware into the provided buffer using environment
+ * variables to determine the firmware file path, address, and size. It
supports
+ * multiple firmware entries by using indexed environment variable names such
as
+ * "fw_dir0", "fw_size0", etc.
+ *
+ * Return: Size of total read, negative value when error.
+ */
+int request_firmware_into_buf_via_env(struct udevice *dev,
+ void *buf, u32 offset,
+ unsigned int fw_index)
+{
+ char var_name[32];
+ size_t size;
+ int ret;
+
+ for (unsigned int index = 0; index < fw_index; index++) {
+ snprintf(var_name, sizeof(var_name), "fw_dir%u", index);
+ const char *name = env_get(var_name);
+
+ if (!name) {
+ printf("Error: env var %s not set.\n", var_name);
+ goto fail;
+ }
+
+ snprintf(var_name, sizeof(var_name), "fw_size%u", index);
+ size = env_get_hex(var_name, 0);
+ if (!size) {
+ printf("Error: env var %s is invalid or zero.\n",
var_name);
+ goto fail;
+ }
+
+ ret = request_firmware_into_buf(dev, name, buf, size, offset);
+ if (ret < 0) {
+ printf("Error: Failed to load firmware %s, size
0x%zx.\n",
+ name, size);
+ return ret;
+ }
+
+ buf = (void *)((uintptr_t)buf + size);
+ }
+
+ return 0;
+fail:
+ printf("Error: Failed to load firmware via environment variables.\n"
+ "Set these environment variables for each firmware index:\n"
+ " fw_dirN - path to firmware file (e.g., fw_dir0)\n"
+ " fw_sizeN - size of firmware (e.g., fw_size0)\n"
+ "Where N is the firmware index (0, 1, ...).\n");
+
+ return -EINVAL;
+}
+
static int fs_loader_of_to_plat(struct udevice *dev)
{
u32 phandlepart[2];
diff --git a/include/fs_loader.h b/include/fs_loader.h
index 5eb5b7ab4a1..0d130daacfc 100644
--- a/include/fs_loader.h
+++ b/include/fs_loader.h
@@ -64,4 +64,22 @@ int request_firmware_into_buf(struct udevice *dev,
* Return: 0 on success, negative value on error
*/
int get_fs_loader(struct udevice **dev);
+
+/**
+ * request_firmware_into_buf_via_env - Load firmware using environment
variables.
+ * @dev: An instance of a driver.
+ * @buf: Address of buffer to load firmware into.
+ * @offset: Offset of a file for start reading into buffer.
+ * @fw_index: Index of the firmware entry to load.
+ *
+ * This function loads firmware into the provided buffer using environment
+ * variables to determine the firmware file path, address, and size. It
supports
+ * multiple firmware entries by using indexed environment variable names such
as
+ * "fw_dir0", "fw_size0", etc.
+ *
+ * Return: Size of total read, negative value when error.
+ */
+int request_firmware_into_buf_via_env(struct udevice *dev,
+ void *buf, u32 offset,
+ unsigned int fw_index);
#endif
--
2.34.1
