src/cpu/x86/smm/save_state.c

   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 */
  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
  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
  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
  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 }