drivers/misc/fsl_sec_mon.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2015 Freescale Semiconductor, Inc.
   4  */
   5
   6 #include <common.h>
   7 #include <fsl_sec_mon.h>
   8
   9 static u32 get_sec_mon_state(void)
  10 {
  11         struct ccsr_sec_mon_regs *sec_mon_regs = (void *)
  12                                                 (CONFIG_SYS_SEC_MON_ADDR);
  13         return sec_mon_in32(&sec_mon_regs->hp_stat) & HPSR_SSM_ST_MASK;
  14 }
  15
  16 static int set_sec_mon_state_non_sec(void)
  17 {
  18         u32 sts;
  19         int timeout = 10;
  20         struct ccsr_sec_mon_regs *sec_mon_regs = (void *)
  21                                                 (CONFIG_SYS_SEC_MON_ADDR);
  22
  23         sts = get_sec_mon_state();
  24
  25         switch (sts) {
  26         /*
  27          * If initial state is check or Non-Secure, then set the Software
  28          * Security Violation Bit and transition to Non-Secure State.
  29          */
  30         case HPSR_SSM_ST_CHECK:
  31                 printf("SEC_MON state transitioning to Non Secure.\n");
  32                 sec_mon_setbits32(&sec_mon_regs->hp_com, HPCOMR_SW_SV);
  33
  34                 /* polling loop till SEC_MON is in Non Secure state */
  35                 while (timeout) {
  36                         sts = get_sec_mon_state();
  37
  38                         if ((sts & HPSR_SSM_ST_MASK) ==
  39                                 HPSR_SSM_ST_NON_SECURE)
  40                                 break;
  41
  42                         udelay(10);
  43                         timeout--;
  44                 }
  45
  46                 if (timeout == 0) {
  47                         printf("SEC_MON state transition timeout.\n");
  48                         return -1;
  49                 }
  50                 break;
  51
  52         /*
  53          * If initial state is Trusted, Secure or Soft-Fail, then first set
  54          * the Software Security Violation Bit and transition to Soft-Fail
  55          * State.
  56          */
  57         case HPSR_SSM_ST_TRUST:
  58         case HPSR_SSM_ST_SECURE:
  59         case HPSR_SSM_ST_SOFT_FAIL:
  60                 printf("SEC_MON state transitioning to Soft Fail.\n");
  61                 sec_mon_setbits32(&sec_mon_regs->hp_com, HPCOMR_SW_SV);
  62
  63                 /* polling loop till SEC_MON is in Soft-Fail state */
  64                 while (timeout) {
  65                         sts = get_sec_mon_state();
  66
  67                         if ((sts & HPSR_SSM_ST_MASK) ==
  68                                 HPSR_SSM_ST_SOFT_FAIL)
  69                                 break;
  70
  71                         udelay(10);
  72                         timeout--;
  73                 }
  74
  75                 if (timeout == 0) {
  76                         printf("SEC_MON state transition timeout.\n");
  77                         return -1;
  78                 }
  79
  80                 timeout = 10;
  81
  82                 /*
  83                  * If SSM Soft Fail to Non-Secure State Transition
  84                  * disable is not set, then set SSM_ST bit and
  85                  * transition to Non-Secure State.
  86                  */
  87                 if ((sec_mon_in32(&sec_mon_regs->hp_com) &
  88                         HPCOMR_SSM_SFNS_DIS) == 0) {
  89                         printf("SEC_MON state transitioning to Non Secure.\n");
  90                         sec_mon_setbits32(&sec_mon_regs->hp_com, HPCOMR_SSM_ST);
  91
  92                         /* polling loop till SEC_MON is in Non Secure*/
  93                         while (timeout) {
  94                                 sts = get_sec_mon_state();
  95
  96                                 if ((sts & HPSR_SSM_ST_MASK) ==
  97                                         HPSR_SSM_ST_NON_SECURE)
  98                                         break;
  99
 100                                 udelay(10);
 101                                 timeout--;
 102                         }
 103
 104                         if (timeout == 0) {
 105                                 printf("SEC_MON state transition timeout.\n");
 106                                 return -1;
 107                         }
 108                 }
 109                 break;
 110         default:
 111                 printf("SEC_MON already in Non Secure state.\n");
 112                 return 0;
 113         }
 114         return 0;
 115 }
 116
 117 static int set_sec_mon_state_soft_fail(void)
 118 {
 119         u32 sts;
 120         int timeout = 10;
 121         struct ccsr_sec_mon_regs *sec_mon_regs = (void *)
 122                                                 (CONFIG_SYS_SEC_MON_ADDR);
 123
 124         printf("SEC_MON state transitioning to Soft Fail.\n");
 125         sec_mon_setbits32(&sec_mon_regs->hp_com, HPCOMR_SW_FSV);
 126
 127         /* polling loop till SEC_MON is in Soft-Fail state */
 128         while (timeout) {
 129                 sts = get_sec_mon_state();
 130
 131                 if ((sts & HPSR_SSM_ST_MASK) ==
 132                         HPSR_SSM_ST_SOFT_FAIL)
 133                         break;
 134
 135                 udelay(10);
 136                 timeout--;
 137         }
 138
 139         if (timeout == 0) {
 140                 printf("SEC_MON state transition timeout.\n");
 141                 return -1;
 142         }
 143         return 0;
 144 }
 145
 146 int set_sec_mon_state(u32 state)
 147 {
 148         int ret = -1;
 149
 150         switch (state) {
 151         case HPSR_SSM_ST_NON_SECURE:
 152                 ret = set_sec_mon_state_non_sec();
 153                 break;
 154         case HPSR_SSM_ST_SOFT_FAIL:
 155                 ret = set_sec_mon_state_soft_fail();
 156                 break;
 157         default:
 158                 printf("SEC_MON state transition not supported.\n");
 159                 return 0;
 160         }
 161
 162         return ret;
 163 }