xref: /aosp_15_r20/external/coreboot/src/include/mrc_cache.h (revision b9411a12aaaa7e1e6a6fb7c5e057f44ee179a49c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 
3 #ifndef _COMMON_MRC_CACHE_H_
4 #define _COMMON_MRC_CACHE_H_
5 
6 #include <stddef.h>
7 #include <stdint.h>
8 #include <commonlib/region.h>
9 
10 enum {
11 	MRC_TRAINING_DATA,
12 	MRC_VARIABLE_DATA,
13 };
14 
15 /*
16  * It's up to the caller to decide when to retrieve and stash data. There is
17  * differentiation on recovery mode CONFIG(HAS_RECOVERY_MRC_CACHE), but that's
18  * only for locating where to retrieve and save the data. If a platform doesn't
19  * want to update the data then it shouldn't stash the data for saving.
20  * Similarly, if the platform doesn't need the data for booting because of a
21  * policy don't request the data.
22  */
23 
24 /* Get and stash data for saving provided the type passed in. */
25 
26 /**
27  * mrc_cache_load_current
28  *
29  * Fill in the buffer with the latest slot data.  This will be a
30  * common entry point for ARM platforms.  Returns < 0 on error, size
31  * of the returned data on success.
32  */
33 ssize_t mrc_cache_load_current(int type, uint32_t version, void *buffer,
34 			       size_t buffer_size);
35 /**
36  * mrc_cache_mmap_leak
37  *
38  * Return a pointer to a buffer with the latest slot data.  An mmap
39  * will be executed (without a matching unmap).  This will be a common
40  * entry point for platforms where mmap is considered a noop, like x86
41  */
42 void *mrc_cache_current_mmap_leak(int type, uint32_t version,
43 				  size_t *data_size);
44 /**
45  * Returns < 0 on error, 0 on success.
46  */
47 int mrc_cache_stash_data(int type, uint32_t version, const void *data,
48 			 size_t size);
49 
50 /**
51  * API to locate the FSP Non-Volatile Storage Data (aka memory training data)
52  * and store into the NVS.
53  */
54 void save_memory_training_data(void);
55 
56 #endif /* _COMMON_MRC_CACHE_H_ */
57