[PATCH 6/7] mach-snapdragon: board interface to enforce fdt

[Jorge Ramirez-Ortiz <jorge.ramirez@oss.qualcomm.com>]

Some platforms might require the external fdt to boot.

This change provides a mechanism to the board initializaion code to make
the requet explicit.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez@oss.qualcomm.com>
---
 arch/arm/mach-snapdragon/board.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm/mach-snapdragon/board.c b/arch/arm/mach-snapdragon/board.c
index 2ef936aab75..1bca9dce20f 100644
--- a/arch/arm/mach-snapdragon/board.c
+++ b/arch/arm/mach-snapdragon/board.c
@@ -150,7 +150,13 @@ static void show_psci_version(void)
 /* We support booting U-Boot with an internal DT when running as a first-stage bootloader
  * or for supporting quirky devices where it's easier to leave the downstream DT in place
  * to improve ABL compatibility. Otherwise, we use the DT provided by ABL.
+ *
+ * Alternatively the board can enforce the external fdt.
  */
+bool __weak qcom_board_fdt_external(void)
+{
+	return false;
+}
 int board_fdt_blob_setup(void **fdtp)
 {
 	struct fdt_header *fdt;
@@ -161,6 +167,12 @@ int board_fdt_blob_setup(void **fdtp)
 	external_valid = fdt && !fdt_check_header(fdt);
 	internal_valid = !fdt_check_header(*fdtp);
 
+	if (qcom_board_fdt_external() && external_valid) {
+		debug("Using external FDT\n");
+		*fdtp = fdt;
+		goto out;
+	}
+
 	/*
 	 * There is no point returning an error here, U-Boot can't do anything useful in this situation.
 	 * Bail out while we can still print a useful error message.
@@ -178,6 +190,7 @@ int board_fdt_blob_setup(void **fdtp)
 		*fdtp = fdt;
 	}
 
+out:
 	/*
 	 * Parse the /memory node while we're here,
 	 * this makes it easy to do other things early.
-- 
2.34.1