The existing logic for handling receiving a devicetree from a previous
phase is quite complicated. Simplify it in preparation for introducing
standard passage.
Add a Kconfig called OF_PASSAGE which indicates that the devicetree
must come from standard passage.
Signed-off-by: Simon Glass <s...@chromium.org>
---
Changes in v3:
- Add new patch to redo how a devicetree is set up
dts/Kconfig | 8 ++++++++
lib/fdtdec.c | 34 ++++++----------------------------
2 files changed, 14 insertions(+), 28 deletions(-)
diff --git a/dts/Kconfig b/dts/Kconfig
index c544f948a15..57101bddabb 100644
--- a/dts/Kconfig
+++ b/dts/Kconfig
@@ -159,6 +159,14 @@ config OF_EMBED
and development only and is not recommended for production devices.
Boards in the mainline U-Boot tree should not use it.
+config OF_PASSAGE
+ bool "DTB is provided by a standard passage, in a bloblist"
+ help
+ Select this to read the devicetree using the standard passage
+ mechanism, i.e. from a previous phase in bloblist using arch-specific
+ register conventions. If enabled, the previous phase must provide
+ the devicetree, or U-Boot will not function correctly.
+
endchoice
config OF_INITIAL_DTB_READONLY
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index f09c9926a7a..8559616873b 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -1689,35 +1689,13 @@ void fdtdec_setup_embed(void)
int fdtdec_setup(void)
{
- int ret = -ENOENT;
-
- /*
- * If allowing a bloblist, check that first. There was discussion about
- * adding an OF_BLOBLIST Kconfig, but this was rejected.
- *
- * The necessary test is whether the previous phase passed a bloblist,
- * not whether this phase creates one.
- */
- if (CONFIG_IS_ENABLED(BLOBLIST) &&
- (xpl_prev_phase() != PHASE_TPL ||
- IS_ENABLED(CONFIG_TPL_BLOBLIST))) {
- ret = bloblist_maybe_init();
- if (!ret) {
- gd->fdt_blob = bloblist_find(BLOBLISTT_CONTROL_FDT, 0);
- if (gd->fdt_blob) {
- gd->fdt_src = FDTSRC_BLOBLIST;
- log_debug("Devicetree is in bloblist at %p\n",
- gd->fdt_blob);
- ret = 0;
- } else {
- log_debug("No FDT found in bloblist\n");
- ret = -ENOENT;
- }
- }
- }
+ int ret;
- /* Otherwise, the devicetree is typically appended to U-Boot */
- if (ret) {
+ if (CONFIG_IS_ENABLED(OF_BLOBLIST)) {
+ printf("Previous phase failed to provide standard passage\n");
+ return -ENOENT;
+ } else {
+ /* The devicetree is typically appended to U-Boot */
if (IS_ENABLED(CONFIG_OF_SEPARATE)) {
gd->fdt_blob = fdt_find_separate();
gd->fdt_src = FDTSRC_SEPARATE;
--
2.43.0
