[U-Boot] [PATCH v1 04/07] fdtdec: allow board to provide fdt for CONFIG_OF_SEPARATE

Jorge Ramirez-Ortiz
2018-01-10T10:34:37Z

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)
--
2.7.4