1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Copyright (C) 2014 Google, Inc 4 * Copyright (C) 2015 Bin Meng <bmeng.cn@gmail.com> 5 */ 6 7 #ifndef _ASM_MRCCACHE_H 8 #define _ASM_MRCCACHE_H 9 10 #include <compiler.h> 11 12 #define MRC_DATA_ALIGN 0x100 13 #define MRC_DATA_SIGNATURE (('M' << 0) | ('R' << 8) | \ 14 ('C' << 16) | ('D'<<24)) 15 16 #define MRC_DATA_HEADER_SIZE 32 17 18 struct __packed mrc_data_container { 19 u32 signature; /* "MRCD" */ 20 u32 data_size; /* Size of the 'data' field */ 21 u32 checksum; /* IP style checksum */ 22 u32 reserved; /* For header alignment */ 23 u8 data[0]; /* Variable size, platform/run time dependent */ 24 }; 25 26 struct mrc_region { 27 u32 base; 28 u32 offset; 29 u32 length; 30 }; 31 32 /* Types of MRC data */ 33 enum mrc_type_t { 34 MRC_TYPE_NORMAL, 35 MRC_TYPE_VAR, 36 37 MRC_TYPE_COUNT, 38 }; 39 40 struct udevice; 41 42 /** 43 * mrccache_find_current() - find the latest MRC cache record 44 * 45 * This searches the MRC cache region looking for the latest record to use 46 * for setting up SDRAM 47 * 48 * @entry: Position and size of MRC cache in SPI flash 49 * @return pointer to latest record, or NULL if none 50 */ 51 struct mrc_data_container *mrccache_find_current(struct mrc_region *entry); 52 53 /** 54 * mrccache_reserve() - reserve MRC data on the stack 55 * 56 * This copies MRC data pointed by gd->arch.mrc_output to a new place on the 57 * stack with length gd->arch.mrc_output_len, and updates gd->arch.mrc_output 58 * to point to the new place once the migration is done. 59 * 60 * This routine should be called by reserve_arch() before U-Boot is relocated 61 * when MRC cache is enabled. 62 * 63 * @return 0 always 64 */ 65 int mrccache_reserve(void); 66 67 /** 68 * mrccache_get_region() - get MRC region on the SPI flash 69 * 70 * This gets MRC region whose offset and size are described in the device tree 71 * as a subnode to the SPI flash. This tries to find the SPI flash device 72 * (without probing it), falling back to looking for the devicetree node if 73 * driver model is not inited or the SPI flash is not found. 74 * 75 * @type: Type of MRC data to use 76 * @devp: Returns pointer to the SPI flash device, if found 77 * @entry: Position and size of MRC cache in SPI flash 78 * @return 0 if success, -ENOENT if SPI flash node does not exist in the 79 * device tree, -EPERM if MRC region subnode does not exist in the device 80 * tree, -EINVAL if MRC region properties format is incorrect, other error 81 * if SPI flash probe failed. 82 */ 83 int mrccache_get_region(enum mrc_type_t type, struct udevice **devp, 84 struct mrc_region *entry); 85 86 /** 87 * mrccache_save() - save MRC data to the SPI flash 88 * 89 * This saves MRC data stored previously by gd->arch.mrc_output to a proper 90 * place within the MRC region on the SPI flash. 91 * 92 * @return 0 if saved to SPI flash successfully, other error if failed 93 */ 94 int mrccache_save(void); 95 96 /** 97 * mrccache_spl_save() - Save to the MRC region from SPL 98 * 99 * When SPL is used to set up the memory controller we want to save the MRC 100 * data in SPL to avoid needing to pass it up to U-Boot proper to save. This 101 * function handles that. 102 * 103 * @return 0 if saved to SPI flash successfully, other error if failed 104 */ 105 int mrccache_spl_save(void); 106 107 #endif /* _ASM_MRCCACHE_H */ 108