1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2016 Socionext Inc.
4  *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
5  */
6 
7 #include <common.h>
8 #include <mmc.h>
9 #include <spl.h>
10 
11 u32 spl_boot_mode(const u32 boot_device)
12 {
13 	struct mmc *mmc;
14 
15 	/*
16 	 * work around a bug in the Boot ROM of LD4, Pro4, and sLD8:
17 	 *
18 	 * The boot ROM in these SoCs breaks the PARTITION_CONFIG [179] of
19 	 * Extended CSD register; when switching to the Boot Partition 1, the
20 	 * Boot ROM should issue the SWITCH command (CMD6) with Set Bits for
21 	 * the Access Bits, but in fact it uses Write Byte for the Access Bits.
22 	 * As a result, the BOOT_PARTITION_ENABLE field of the PARTITION_CONFIG
23 	 * is lost.  This bug was fixed for PH1-Pro5 and later SoCs.
24 	 *
25 	 * Fixup mmc->part_config here because it is used to determine the
26 	 * partition which the U-Boot image is read from.
27 	 */
28 	mmc = find_mmc_device(0);
29 	mmc->part_config &= ~EXT_CSD_BOOT_PART_NUM(PART_ACCESS_MASK);
30 	mmc->part_config |= EXT_CSD_BOOT_PARTITION_ENABLE;
31 
32 	return MMCSD_MODE_EMMCBOOT;
33 }
34