1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Copyright (C) 2014 Google, Inc
4 * Copyright (C) 2015 Bin Meng <bmeng.cn@gmail.com>
7 #ifndef _ASM_MRCCACHE_H
8 #define _ASM_MRCCACHE_H
10 #define MRC_DATA_ALIGN 0x1000
11 #define MRC_DATA_SIGNATURE (('M' << 0) | ('R' << 8) | \
12 ('C' << 16) | ('D'<<24))
14 #define MRC_DATA_HEADER_SIZE 32
16 struct __packed mrc_data_container {
17 u32 signature; /* "MRCD" */
18 u32 data_size; /* Size of the 'data' field */
19 u32 checksum; /* IP style checksum */
20 u32 reserved; /* For header alignment */
21 u8 data[0]; /* Variable size, platform/run time dependent */
33 * mrccache_find_current() - find the latest MRC cache record
35 * This searches the MRC cache region looking for the latest record to use
36 * for setting up SDRAM
38 * @entry: Position and size of MRC cache in SPI flash
39 * @return pointer to latest record, or NULL if none
41 struct mrc_data_container *mrccache_find_current(struct mrc_region *entry);
44 * mrccache_update() - update the MRC cache with a new record
46 * This writes a new record to the end of the MRC cache region. If the new
47 * record is the same as the latest record then the write is skipped
49 * @sf: SPI flash to write to
50 * @entry: Position and size of MRC cache in SPI flash
51 * @cur: Record to write
52 * @return 0 if updated, -EEXIST if the record is the same as the latest
53 * record, -EINVAL if the record is not valid, other error if SPI write failed
55 int mrccache_update(struct udevice *sf, struct mrc_region *entry,
56 struct mrc_data_container *cur);
59 * mrccache_reserve() - reserve MRC data on the stack
61 * This copies MRC data pointed by gd->arch.mrc_output to a new place on the
62 * stack with length gd->arch.mrc_output_len, and updates gd->arch.mrc_output
63 * to point to the new place once the migration is done.
65 * This routine should be called by reserve_arch() before U-Boot is relocated
66 * when MRC cache is enabled.
70 int mrccache_reserve(void);
73 * mrccache_get_region() - get MRC region on the SPI flash
75 * This gets MRC region whose offset and size are described in the device tree
76 * as a subnode to the SPI flash. If a non-NULL device pointer is supplied,
77 * this also probes the SPI flash device and returns its device pointer for
78 * the caller to use later.
80 * Be careful when calling this routine with a non-NULL device pointer:
81 * - driver model initialization must be complete
82 * - calling in the pre-relocation phase may bring some side effects during
83 * the SPI flash device probe (eg: for SPI controllers on a PCI bus, it
84 * triggers PCI bus enumeration during which insufficient memory issue
85 * might be exposed and it causes subsequent SPI flash probe fails).
87 * @devp: Returns pointer to the SPI flash device
88 * @entry: Position and size of MRC cache in SPI flash
89 * @return 0 if success, -ENOENT if SPI flash node does not exist in the
90 * device tree, -EPERM if MRC region subnode does not exist in the device
91 * tree, -EINVAL if MRC region properties format is incorrect, other error
92 * if SPI flash probe failed.
94 int mrccache_get_region(struct udevice **devp, struct mrc_region *entry);
97 * mrccache_save() - save MRC data to the SPI flash
99 * This saves MRC data stored previously by gd->arch.mrc_output to a proper
100 * place within the MRC region on the SPI flash.
102 * @return 0 if saved to SPI flash successfully, other error if failed
104 int mrccache_save(void);
106 #endif /* _ASM_MRCCACHE_H */