Hi Ilias,
On Tue, 26 Oct 2021 at 07:56, Ilias Apalodimas ilias.apalodimas@linaro.org wrote:
Hi Simon,
As I said here [1], this is moving on an entirely different direction I had in mind. I'd much prefer starting the discussions for a solution that allows us to scale.
I am missing the point here. Is there something in the plans that I don't know about?
FWIW I think the current code is still not clean for my taste. Commit 3b595da441cf ("fdtdec: allow board to provide fdt for CONFIG_OF_SEPARATE") allowed this function to be used regardless of the config options. IMHO we should have 2 clear options:
- U-Boot provides the DTB
Supported with: OF_SEPARATE
- It's somehow passed over to U-Boot
Supported with: OF_SEPARATE + OF_BOARD
I actually hit this problem with my qemu testing, in that it is actually not possible to use U-Boot's devicetree without hacking the code. We need to be able to select this feature explicitly, or turn it off, at least for development.
Regards, Simon
On Mon, Oct 25, 2021 at 06:23:44PM -0600, Simon Glass wrote:
At present this override function is called even when OF_BOARD Is not enabled. This makes it impossible to disable this feature and in fact makes the OF_BOARD option useless.
Reinstate its intended purpose, so that it is possible to switch between the appended devicetree and one provided by the board's custom function.
Signed-off-by: Simon Glass sjg@chromium.org
Changes in v5:
- Add new patches to clean up fdtdec_setup() and surrounds
include/fdtdec.h | 7 +++++-- lib/fdtdec.c | 17 +++++++++++------ 2 files changed, 16 insertions(+), 8 deletions(-)
diff --git a/include/fdtdec.h b/include/fdtdec.h index 386f6611294..b2faa84008e 100644 --- a/include/fdtdec.h +++ b/include/fdtdec.h @@ -1170,8 +1170,11 @@ int fdtdec_resetup(int *rescan);
/**
- Board-specific FDT initialization. Returns the address to a device tree blob.
- Called when CONFIG_OF_BOARD is defined, or if CONFIG_OF_SEPARATE is defined
- and the board implements it.
- Called when CONFIG_OF_BOARD is defined.
- The existing devicetree is available at gd->fdt_blob
*/
- @returns new devicetree blob pointer
void *board_fdt_blob_setup(void);
diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 067c27d0aa3..da36dffec62 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -1203,11 +1203,12 @@ static int uncompress_blob(const void *src, ulong sz_src, void **dstp) return 0; }
-/*
- For CONFIG_OF_SEPARATE, the board may optionally implement this to
- provide and/or fixup the fdt.
+/**
- fdt_find_separate() - Find a devicetree at the end of the image
*/
- @return pointer to FDT blob
-__weak void *board_fdt_blob_setup(void) +static void *fdt_find_separate(void) { void *fdt_blob = NULL; #ifdef CONFIG_SPL_BUILD @@ -1623,11 +1624,15 @@ int fdtdec_setup(void) int ret;
/* The devicetree is typically appended to U-Boot */
if (IS_ENABLED(CONFIG_OF_SEPARATE) || IS_ENABLED(CONFIG_OF_BOARD))gd->fdt_blob = board_fdt_blob_setup();
if (IS_ENABLED(CONFIG_OF_SEPARATE))gd->fdt_blob = fdt_find_separate(); else /* embed dtb in ELF file for testing / development */ gd->fdt_blob = dtb_dt_embedded();/* Allow the board to override the fdt address. */if (IS_ENABLED(CONFIG_OF_BOARD))gd->fdt_blob = board_fdt_blob_setup();if (!IS_ENABLED(CONFIG_SPL_BUILD)) { /* Allow the early environment to override the fdt address */ gd->fdt_blob = map_sysmem(env_get_ulong("fdtcontroladdr", 16,-- 2.33.0.1079.g6e70778dc9-goog
[1] https://lore.kernel.org/u-boot/YXekTkeL73NM0UOU@apalos.home/
Regards /Ilias