xref: /aosp_15_r20/external/coreboot/src/cpu/x86/smm/save_state.c (revision b9411a12aaaa7e1e6a6fb7c5e057f44ee179a49c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 
3 #include <commonlib/bsd/helpers.h>
4 #include <cpu/x86/save_state.h>
5 #include <cpu/x86/smm.h>
6 #include <types.h>
7 
8 /* These are weakly linked such that platforms can link only the save state
9    ops they actually require. */
10 const struct smm_save_state_ops *legacy_ops __weak = NULL;
11 const struct smm_save_state_ops *em64t100_ops __weak = NULL;
12 const struct smm_save_state_ops *em64t101_ops __weak = NULL;
13 const struct smm_save_state_ops *amd64_ops __weak = NULL;
14 
15 static const struct smm_save_state_ops *save_state;
16 
17 /* Returns -1 on failure, 0 on success */
init_save_state(void)18 static int init_save_state(void)
19 {
20 	const uint32_t revision = smm_revision();
21 	int i;
22 	static bool initialized = false;
23 	const struct smm_save_state_ops *save_state_ops[] = {
24 		legacy_ops,
25 		em64t100_ops,
26 		em64t101_ops,
27 		amd64_ops,
28 	};
29 
30 	if (initialized)
31 		return 0;
32 
33 	for (i = 0; i < ARRAY_SIZE(save_state_ops); i++) {
34 		const struct smm_save_state_ops *ops = save_state_ops[i];
35 		const uint32_t *rev;
36 
37 		if (ops == NULL)
38 			continue;
39 
40 		for (rev = ops->revision_table; *rev != SMM_REV_INVALID; rev++)
41 			if (*rev == revision) {
42 				save_state = ops;
43 				initialized = true;
44 				return 0;
45 			}
46 	}
47 
48 	return -1;
49 }
50 
get_apmc_node(u8 cmd)51 int get_apmc_node(u8 cmd)
52 {
53 	if (init_save_state())
54 		return -1;
55 
56 	return save_state->apmc_node(cmd);
57 }
58 
get_save_state_reg(const enum cpu_reg reg,const int node,void * out,const uint8_t length)59 int get_save_state_reg(const enum cpu_reg reg, const int node, void *out, const uint8_t length)
60 {
61 	if (init_save_state())
62 		return -1;
63 
64 	if (node > CONFIG_MAX_CPUS)
65 		return -1;
66 
67 	return save_state->get_reg(reg, node, out, length);
68 }
69 
set_save_state_reg(const enum cpu_reg reg,const int node,void * in,const uint8_t length)70 int set_save_state_reg(const enum cpu_reg reg, const int node, void *in, const uint8_t length)
71 {
72 	if (init_save_state())
73 		return -1;
74 
75 	if (node > CONFIG_MAX_CPUS)
76 		return -1;
77 
78 	return save_state->set_reg(reg, node, in, length);
79 }
80