Revert "fdtdec: drop needlessly convoluted CONFIG_PHANDLE_CHECK_SEQ"

The fdt_path_offset() function is slow since it must scan the tree.
This substantial overhead now applies to all boards.

The original code may not be ideal but it is fit for purpose and is only
needed on a few boards.

Reverting this reduces time to set up driver model by about 30ms.

Before revert:

Accumulated time:
                47,170  dm_r
                53,237  dm_spl
               572,986  dm_f

Accumulated time:
                44,598  dm_r
                50,347  dm_spl
               549,133  dm_f

This reverts commit 26f981f295.

Signed-off-by: Simon Glass <sjg@chromium.org>

configs/am65x_evm_a53_defconfig

@@ -179,3 +179,4 @@ CONFIG_USB_GADGET_VENDOR_NUM=0x0451
 CONFIG_USB_GADGET_PRODUCT_NUM=0x6162
 CONFIG_USB_GADGET_DOWNLOAD=y
 CONFIG_OF_LIBFDT_OVERLAY=y
+CONFIG_PHANDLE_CHECK_SEQ=y

configs/evb-ast2600_defconfig

@@ -120,3 +120,4 @@ CONFIG_WDT=y
 CONFIG_SHA384=y
 CONFIG_HEXDUMP=y
 # CONFIG_EFI_LOADER is not set
+CONFIG_PHANDLE_CHECK_SEQ=y

configs/sama7g5ek_mmc1_defconfig

@@ -79,3 +79,4 @@ CONFIG_TIMER=y
 CONFIG_MCHP_PIT64B_TIMER=y
 CONFIG_OF_LIBFDT_OVERLAY=y
 # CONFIG_EFI_LOADER_HII is not set
+CONFIG_PHANDLE_CHECK_SEQ=y

configs/sama7g5ek_mmc_defconfig

@@ -79,3 +79,4 @@ CONFIG_TIMER=y
 CONFIG_MCHP_PIT64B_TIMER=y
 CONFIG_OF_LIBFDT_OVERLAY=y
 # CONFIG_EFI_LOADER_HII is not set
+CONFIG_PHANDLE_CHECK_SEQ=y

lib/Kconfig

@@ -1045,6 +1045,13 @@ config LMB_RESERVED_REGIONS
 	  Define the number of supported reserved regions in the library logical
 	  memory blocks.
 
+config PHANDLE_CHECK_SEQ
+	bool "Enable phandle check while getting sequence number"
+	help
+	  When there are multiple device tree nodes with same name,
+          enable this config option to distinguish them using
+	  phandles in fdtdec_get_alias_seq() function.
+
 endmenu
 
 menu "FWU Multi Bank Updates"

lib/fdtdec.c

@@ -519,8 +519,11 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
 		 * Adding an extra check to distinguish DT nodes with
 		 * same name
 		 */
-		if (offset != fdt_path_offset(blob, prop))
-			continue;
+		if (IS_ENABLED(CONFIG_PHANDLE_CHECK_SEQ)) {
+			if (fdt_get_phandle(blob, offset) !=
+			    fdt_get_phandle(blob, fdt_path_offset(blob, prop)))
+				continue;
+		}
 
 		val = trailing_strtol(name);
 		if (val != -1) {