u-boot-initial-env: rework make targetRFT/ci-testing

With LTO enabled the U-Boot initial environment is no longer stored
in an easy accessible section in env/common.o. I.e. the section name
changes from build to build, its content maybe compressed and it is
annotated with additional data.

Drop trying to read the initial env with elf tools from the compiler
specific object file in favour of adding and using a host tool with
the only functionality of printing the initial env to stdout.

See also:
https://lore.kernel.org/all/927b122e-1f62-e790-f5ca-30bae4332c77@foss.st.com/

Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
Acked-by: Pali Rohár <pali@kernel.org>

1 files changed, 44 insertions, 0 deletions

diff --git a/tools/printinitialenv.c b/tools/printinitialenv.c
new file mode 100644
index 0000000..c58b234
--- /dev/null
+++ b/tools/printinitialenv.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2022
+ * Max Krummenacher, Toradex
+ *
+ * Snippets taken from tools/env/fw_env.c
+ *
+ * This prints the list of default environment variables as currently
+ * configured.
+ *
+ */
+
+#include <stdio.h>
+
+/* Pull in the current config to define the default environment */
+#include <linux/kconfig.h>
+
+#ifndef __ASSEMBLY__
+#define __ASSEMBLY__ /* get only #defines from config.h */
+#include <config.h>
+#undef	__ASSEMBLY__
+#else
+#include <config.h>
+#endif
+
+#define DEFAULT_ENV_INSTANCE_STATIC
+#include <generated/environment.h>
+#include <env_default.h>
+
+int main(void)
+{
+	char *env, *nxt;
+
+	for (env = default_environment; *env; env = nxt + 1) {
+		for (nxt = env; *nxt; ++nxt) {
+			if (nxt >= &default_environment[sizeof(default_environment)]) {
+				fprintf(stderr, "## Error: environment not terminated\n");
+				return -1;
+			}
+		}
+		printf("%s\n", env);
+	}
+	return 0;
+}