fdt: Avoid early panic() when there is no FDT present
CONFIG_OF_CONTROL requires a valid device tree. However, we cannot call
panic() before the console is set up since the message does not appear,
and we get a silent failure.
Remove the panic from fdtdec_check_fdt() and provide a new function to
prepare the fdt for use. This will be called after the console is ready.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/include/fdtdec.h b/include/fdtdec.h
index bde9873..6249f22 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -155,8 +155,21 @@
int fdtdec_get_is_enabled(const void *blob, int node);
/**
- * Checks whether we have a valid fdt available to control U-Boot, and panic
- * if not.
+ * Make sure we have a valid fdt available to control U-Boot.
+ *
+ * If not, a message is printed to the console if the console is ready.
+ *
+ * @return 0 if all ok, -1 if not
+ */
+int fdtdec_prepare_fdt(void);
+
+/**
+ * Checks that we have a valid fdt available to control U-Boot.
+
+ * However, if not then for the moment nothing is done, since this function
+ * is called too early to panic().
+ *
+ * @returns 0
*/
int fdtdec_check_fdt(void);
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 4ca442a..5239e79 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -262,17 +262,31 @@
return num_found;
}
+int fdtdec_check_fdt(void)
+{
+ /*
+ * We must have an FDT, but we cannot panic() yet since the console
+ * is not ready. So for now, just assert(). Boards which need an early
+ * FDT (prior to console ready) will need to make their own
+ * arrangements and do their own checks.
+ */
+ assert(!fdtdec_prepare_fdt());
+ return 0;
+}
+
/*
* This function is a little odd in that it accesses global data. At some
* point if the architecture board.c files merge this will make more sense.
* Even now, it is common code.
*/
-int fdtdec_check_fdt(void)
+int fdtdec_prepare_fdt(void)
{
- /* We must have an fdt */
- if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob))
- panic("No valid fdt found - please append one to U-Boot\n"
- "binary or define CONFIG_OF_EMBED\n");
+ if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) {
+ printf("No valid FDT found - please append one to U-Boot "
+ "binary, use u-boot-dtb.bin or define "
+ "CONFIG_OF_EMBED\n");
+ return -1;
+ }
return 0;
}