From: Rob Clark robdclark@gmail.com
Similar to CONFIG_OF_BOARD, but in this case the fdt is still built by u-boot build. This allows the board to patch the fdt, etc.
In the specific case of dragonboard 410c, we pass the u-boot generated fdt to the previous stage of bootloader (by embedding it in the u-boot.img that is loaded by lk/aboot), which patches the fdt and passes it back to u-boot.
Signed-off-by: Rob Clark robdclark@gmail.com --- include/fdtdec.h | 3 ++- lib/fdtdec.c | 35 +++++++++++++++++++++++------------ 2 files changed, 25 insertions(+), 13 deletions(-)
diff --git a/include/fdtdec.h b/include/fdtdec.h index 0fb3e07..4afb9ac 100644 --- a/include/fdtdec.h +++ b/include/fdtdec.h @@ -990,7 +990,8 @@ int fdtdec_setup(void);
/** * Board-specific FDT initialization. Returns the address to a device tree blob. - * Called when CONFIG_OF_BOARD is defined. + * Called when CONFIG_OF_BOARD is defined, or if CONFIG_OF_SEPARATE is defined + * and the board implements it. */ void *board_fdt_blob_setup(void);
diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 30ec6b9..cc3dfd6 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -1272,6 +1272,28 @@ static int uncompress_blob(const void *src, ulong sz_src, void **dstp) # endif #endif
+#if CONFIG_IS_ENABLED(OF_SEPARATE) +/* + * For CONFIG_OF_SEPARATE, the board may optionally implement this to + * provide and/or fixup the fdt. + */ +__weak void *board_fdt_blob_setup(void) +{ + void *fdt_blob = NULL; +#ifdef CONFIG_SPL_BUILD + /* FDT is at end of BSS unless it is in a different memory region */ + if (IS_ENABLED(CONFIG_SPL_SEPARATE_BSS)) + fdt_blob = (ulong *)&_image_binary_end; + else + fdt_blob = (ulong *)&__bss_end; +#else + /* FDT is at end of image */ + fdt_blob = (ulong *)&_end; +#endif + return fdt_blob; +} +#endif + int fdtdec_setup(void) { #if CONFIG_IS_ENABLED(OF_CONTROL) @@ -1285,18 +1307,7 @@ int fdtdec_setup(void) # else gd->fdt_blob = __dtb_dt_begin; # endif -# elif defined CONFIG_OF_SEPARATE -# ifdef CONFIG_SPL_BUILD - /* FDT is at end of BSS unless it is in a different memory region */ - if (IS_ENABLED(CONFIG_SPL_SEPARATE_BSS)) - gd->fdt_blob = (ulong *)&_image_binary_end; - else - gd->fdt_blob = (ulong *)&__bss_end; -# else - /* FDT is at end of image */ - gd->fdt_blob = (ulong *)&_end; -# endif -# elif defined(CONFIG_OF_BOARD) +# elif defined(CONFIG_OF_BOARD) || defined (CONFIG_OF_SEPARATE) /* Allow the board to override the fdt address. */ gd->fdt_blob = board_fdt_blob_setup(); # elif defined(CONFIG_OF_HOSTFILE)