src/include/smmstore.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #ifndef _SMMSTORE_H_
   4 #define _SMMSTORE_H_
   5
   6 #include <stddef.h>
   7 #include <stdint.h>
   8
   9 #define SMMSTORE_RET_SUCCESS 0
  10 #define SMMSTORE_RET_FAILURE 1
  11 #define SMMSTORE_RET_UNSUPPORTED 2
  12
  13 /* Version 1 */
  14 #define SMMSTORE_CMD_CLEAR 1
  15 #define SMMSTORE_CMD_READ 2
  16 #define SMMSTORE_CMD_APPEND 3
  17
  18 /* Version 2 */
  19 #define SMMSTORE_CMD_INIT 4
  20 #define SMMSTORE_CMD_RAW_READ 5
  21 #define SMMSTORE_CMD_RAW_WRITE 6
  22 #define SMMSTORE_CMD_RAW_CLEAR 7
  23
  24 /* Version 1 */
  25 struct smmstore_params_read {
  26         void *buf;
  27         ssize_t bufsize;
  28 };
  29
  30 struct smmstore_params_append {
  31         void *key;
  32         size_t keysize;
  33         void *val;
  34         size_t valsize;
  35 };
  36
  37 /* Version 2 */
  38 /*
  39  * The Version 2 protocol separates the SMMSTORE into 64KiB blocks, each
  40  * of which can be read/written/cleared in an independent manner. The
  41  * data format isn't specified. See documentation page for more details.
  42  */
  43
  44 #define SMM_BLOCK_SIZE (64 * KiB)
  45
  46 /*
  47  * Sets the communication buffer to use for read and write operations.
  48  */
  49 struct smmstore_params_init {
  50         uint32_t com_buffer;
  51         uint32_t com_buffer_size;
  52 } __packed;
  53
  54 /*
  55  * Returns the number of blocks the SMMSTORE supports and their size.
  56  * For EDK2 this should be at least two blocks with 64 KiB each.
  57  * The mmap_addr is set the memory mapped physical address of the SMMSTORE.
  58  */
  59 struct smmstore_params_info {
  60         uint32_t num_blocks;
  61         uint32_t block_size;
  62         uint32_t mmap_addr;
  63 } __packed;
  64
  65 /*
  66  * Reads a chunk of raw data with size @bufsize from the block specified by
  67  * @block_id starting at @bufoffset.
  68  * The read data is placed in memory pointed to by @buf.
  69  *
  70  * @block_id must be less than num_blocks
  71  * @bufoffset + @bufsize must be less than block_size
  72  */
  73 struct smmstore_params_raw_write {
  74         uint32_t bufsize;
  75         uint32_t bufoffset;
  76         uint32_t block_id;
  77 } __packed;
  78
  79 /*
  80  * Writes a chunk of raw data with size @bufsize to the block specified by
  81  * @block_id starting at @bufoffset.
  82  *
  83  * @block_id must be less than num_blocks
  84  * @bufoffset + @bufsize must be less than block_size
  85  */
  86 struct smmstore_params_raw_read {
  87         uint32_t bufsize;
  88         uint32_t bufoffset;
  89         uint32_t block_id;
  90 } __packed;
  91
  92 /*
  93  * Erases the specified block.
  94  *
  95  * @block_id must be less than num_blocks
  96  */
  97 struct smmstore_params_raw_clear {
  98         uint32_t block_id;
  99 } __packed;
 100
 101
 102 /* SMM handler */
 103 uint32_t smmstore_exec(uint8_t command, void *param);
 104
 105 /* Implementation of Version 1 */
 106 int smmstore_read_region(void *buf, ssize_t *bufsize);
 107 int smmstore_append_data(void *key, uint32_t key_sz, void *value, uint32_t value_sz);
 108 int smmstore_clear_region(void);
 109
 110 /* Implementation of Version 2 */
 111 int smmstore_init(void *buf, size_t len);
 112 int smmstore_rawread_region(uint32_t block_id, uint32_t offset, uint32_t bufsize);
 113 int smmstore_rawwrite_region(uint32_t block_id, uint32_t offset, uint32_t bufsize);
 114 int smmstore_rawclear_region(uint32_t block_id);
 115 #if ENV_RAMSTAGE
 116 int smmstore_get_info(struct smmstore_params_info *info);
 117 #endif
 118
 119 /* Advertise SMMSTORE v2 support */
 120 struct lb_header;
 121 void lb_smmstorev2(struct lb_header *header);
 122
 123 #endif