libfdt: Introduce new ARCH_FIXUP_FDT option

Add new Kconfig option to disable arch_fixup_fdt() calls for cases where
U-Boot shouldn't update memory setup in DTB file.
One example of usage of this option is to boot OS with different memory
setup than U-Boot use.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Simon Glass <sjg@chromium.org>

Kconfig

@@ -342,6 +342,15 @@ config SYS_CLK_FREQ
 	help
 	  TODO: Move CONFIG_SYS_CLK_FREQ for all the architecture
 
+config ARCH_FIXUP_FDT
+	bool "Enable arch_fixup_fdt() call"
+	depends on ARM || MIPS
+	default y
+	help
+	  Enable FDT memory map syncup before OS boot. This feature can be
+	  used for booting OS with different memory setup where the part of
+	  the memory location should be used for different purpose.
+
 endmenu		# Boot images
 
 source "common/Kconfig"

arch/arm/lib/bootm-fdt.c

@@ -25,6 +25,7 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#ifdef CONFIG_ARCH_FIXUP_FDT
 int arch_fixup_fdt(void *blob)
 {
 	bd_t *bd = gd->bd;
@@ -60,3 +61,4 @@ int arch_fixup_fdt(void *blob)
 
 	return 0;
 }
+#endif

arch/arm/lib/bootm.c

@@ -367,8 +367,10 @@ void boot_prep_vxworks(bootm_headers_t *images)
 	if (images->ft_addr) {
 		off = fdt_path_offset(images->ft_addr, "/memory");
 		if (off < 0) {
+#ifdef CONFIG_ARCH_FIXUP_FDT
 			if (arch_fixup_fdt(images->ft_addr))
 				puts("## WARNING: fixup memory failed!\n");
+#endif
 		}
 	}
 #endif

arch/mips/lib/bootm.c

@@ -253,6 +253,7 @@ static int boot_reloc_fdt(bootm_headers_t *images)
 #endif
 }
 
+#ifdef CONFIG_ARCH_FIXUP_FDT
 int arch_fixup_fdt(void *blob)
 {
 #if CONFIG_IS_ENABLED(MIPS_BOOT_FDT) && CONFIG_IS_ENABLED(OF_LIBFDT)
@@ -264,6 +265,7 @@ int arch_fixup_fdt(void *blob)
 	return 0;
 #endif
 }
+#endif
 
 static int boot_setup_fdt(bootm_headers_t *images)
 {

common/image-fdt.c

@@ -458,11 +458,6 @@ __weak int ft_verify_fdt(void *fdt)
 	return 1;
 }
 
-__weak int arch_fixup_fdt(void *blob)
-{
-	return 0;
-}
-
 int image_setup_libfdt(bootm_headers_t *images, void *blob,
 		       int of_size, struct lmb *lmb)
 {
@@ -479,10 +474,12 @@ int image_setup_libfdt(bootm_headers_t *images, void *blob,
 		printf("ERROR: /chosen node create failed\n");
 		goto err;
 	}
+#ifdef CONFIG_ARCH_FIXUP_FDT
 	if (arch_fixup_fdt(blob) < 0) {
 		printf("ERROR: arch-specific fdt fixup failed\n");
 		goto err;
 	}
+#endif
 	if (IMAGE_OF_BOARD_SETUP) {
 		fdt_ret = ft_board_setup(blob, gd->bd);
 		if (fdt_ret) {