efi_loader: move distro_efi_get_fdt_name()

Move distro_efi_get_fdt_name() to a separate C module
and rename it to efi_get_distro_fdt_name().

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

boot/bootmeth_efi.c

@@ -143,62 +143,6 @@ static int distro_efi_check(struct udevice *dev, struct bootflow_iter *iter)
 	return 0;
 }
 
-/**
- * distro_efi_get_fdt_name() - Get the filename for reading the .dtb file
- *
- * @fname: Place to put filename
- * @size: Max size of filename
- * @seq: Sequence number, to cycle through options (0=first)
- * Returns: 0 on success, -ENOENT if the "fdtfile" env var does not exist,
- * -EINVAL if there are no more options, -EALREADY if the control FDT should be
- * used
- */
-static int distro_efi_get_fdt_name(char *fname, int size, int seq)
-{
-	const char *fdt_fname;
-	const char *prefix;
-
-	/* select the prefix */
-	switch (seq) {
-	case 0:
-		/* this is the default */
-		prefix = "/dtb";
-		break;
-	case 1:
-		prefix = "";
-		break;
-	case 2:
-		prefix = "/dtb/current";
-		break;
-	default:
-		return log_msg_ret("pref", -EINVAL);
-	}
-
-	fdt_fname = env_get("fdtfile");
-	if (fdt_fname) {
-		snprintf(fname, size, "%s/%s", prefix, fdt_fname);
-		log_debug("Using device tree: %s\n", fname);
-	} else if (IS_ENABLED(CONFIG_OF_HAS_PRIOR_STAGE)) {
-		strcpy(fname, "<prior>");
-		return log_msg_ret("pref", -EALREADY);
-	/* Use this fallback only for 32-bit ARM */
-	} else if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_ARM64)) {
-		const char *soc = env_get("soc");
-		const char *board = env_get("board");
-		const char *boardver = env_get("boardver");
-
-		/* cf the code in label_boot() which seems very complex */
-		snprintf(fname, size, "%s/%s%s%s%s.dtb", prefix,
-			 soc ? soc : "", soc ? "-" : "", board ? board : "",
-			 boardver ? boardver : "");
-		log_debug("Using default device tree: %s\n", fname);
-	} else {
-		return log_msg_ret("env", -ENOENT);
-	}
-
-	return 0;
-}
-
 /*
  * distro_efi_try_bootflow_files() - Check that files are present
  *
@@ -240,7 +184,7 @@ static int distro_efi_try_bootflow_files(struct udevice *dev,
 	ret = -ENOENT;
 	*fname = '\0';
 	for (seq = 0; ret == -ENOENT; seq++) {
-		ret = distro_efi_get_fdt_name(fname, sizeof(fname), seq);
+		ret = efi_get_distro_fdt_name(fname, sizeof(fname), seq);
 		if (ret == -EALREADY)
 			bflow->flags = BOOTFLOWF_USE_PRIOR_FDT;
 		if (!ret) {
@@ -339,7 +283,7 @@ static int distro_efi_read_bootflow_net(struct bootflow *bflow)
 	sprintf(file_addr, "%lx", fdt_addr);
 
 	/* We only allow the first prefix with PXE */
-	ret = distro_efi_get_fdt_name(fname, sizeof(fname), 0);
+	ret = efi_get_distro_fdt_name(fname, sizeof(fname), 0);
 	if (ret)
 		return log_msg_ret("nam", ret);
 

include/efi_loader.h

@@ -1199,4 +1199,6 @@ efi_status_t efi_load_option_dp_join(struct efi_device_path **dp,
 				     struct efi_device_path *initrd_dp,
 				     struct efi_device_path *fdt_dp);
 
+int efi_get_distro_fdt_name(char *fname, int size, int seq);
+
 #endif /* _EFI_LOADER_H */

lib/efi_loader/Makefile

@@ -59,6 +59,7 @@ obj-y += efi_device_path.o
 obj-$(CONFIG_EFI_DEVICE_PATH_TO_TEXT) += efi_device_path_to_text.o
 obj-$(CONFIG_EFI_DEVICE_PATH_UTIL) += efi_device_path_utilities.o
 obj-y += efi_dt_fixup.o
+obj-y += efi_fdt.o
 obj-y += efi_file.o
 obj-$(CONFIG_EFI_LOADER_HII) += efi_hii.o
 obj-y += efi_image_loader.o

lib/efi_loader/efi_fdt.c

@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Bootmethod for distro boot via EFI
+ *
+ * Copyright 2021 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#include <efi_loader.h>
+#include <env.h>
+#include <errno.h>
+#include <log.h>
+#include <string.h>
+#include <vsprintf.h>
+
+/**
+ * distro_efi_get_fdt_name() - get the filename for reading the .dtb file
+ *
+ * @fname:	buffer for filename
+ * @size:	buffer size
+ * @seq:	sequence number, to cycle through options (0=first)
+ *
+ * Returns:
+ * 0 on success,
+ * -ENOENT if the "fdtfile" env var does not exist,
+ * -EINVAL if there are no more options,
+ * -EALREADY if the control FDT should be used
+ */
+int efi_get_distro_fdt_name(char *fname, int size, int seq)
+{
+	const char *fdt_fname;
+	const char *prefix;
+
+	/* select the prefix */
+	switch (seq) {
+	case 0:
+		/* this is the default */
+		prefix = "/dtb";
+		break;
+	case 1:
+		prefix = "";
+		break;
+	case 2:
+		prefix = "/dtb/current";
+		break;
+	default:
+		return log_msg_ret("pref", -EINVAL);
+	}
+
+	fdt_fname = env_get("fdtfile");
+	if (fdt_fname) {
+		snprintf(fname, size, "%s/%s", prefix, fdt_fname);
+		log_debug("Using device tree: %s\n", fname);
+	} else if (IS_ENABLED(CONFIG_OF_HAS_PRIOR_STAGE)) {
+		strcpy(fname, "<prior>");
+		return log_msg_ret("pref", -EALREADY);
+	/* Use this fallback only for 32-bit ARM */
+	} else if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_ARM64)) {
+		const char *soc = env_get("soc");
+		const char *board = env_get("board");
+		const char *boardver = env_get("boardver");
+
+		/* cf the code in label_boot() which seems very complex */
+		snprintf(fname, size, "%s/%s%s%s%s.dtb", prefix,
+			 soc ? soc : "", soc ? "-" : "", board ? board : "",
+			 boardver ? boardver : "");
+		log_debug("Using default device tree: %s\n", fname);
+	} else {
+		return log_msg_ret("env", -ENOENT);
+	}
+
+	return 0;
+}