arch/nds32/kernel/pm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2008-2017 Andes Technology Corporation
   3
   4 #include <linux/init.h>
   5 #include <linux/suspend.h>
   6 #include <linux/device.h>
   7 #include <linux/printk.h>
   8 #include <asm/suspend.h>
   9 #include <nds32_intrinsic.h>
  10
  11 unsigned int resume_addr;
  12 unsigned int *phy_addr_sp_tmp;
  13
  14 static void nds32_suspend2ram(void)
  15 {
  16         pgd_t *pgdv;
  17         pud_t *pudv;
  18         pmd_t *pmdv;
  19         pte_t *ptev;
  20
  21         pgdv = (pgd_t *)__va((__nds32__mfsr(NDS32_SR_L1_PPTB) &
  22                 L1_PPTB_mskBASE)) + pgd_index((unsigned int)cpu_resume);
  23
  24         pudv = pud_offset(pgdv, (unsigned int)cpu_resume);
  25         pmdv = pmd_offset(pudv, (unsigned int)cpu_resume);
  26         ptev = pte_offset_map(pmdv, (unsigned int)cpu_resume);
  27
  28         resume_addr = ((*ptev) & TLB_DATA_mskPPN)
  29                         | ((unsigned int)cpu_resume & 0x00000fff);
  30
  31         suspend2ram();
  32 }
  33
  34 static void nds32_suspend_cpu(void)
  35 {
  36         while (!(__nds32__mfsr(NDS32_SR_INT_PEND) & wake_mask))
  37                 __asm__ volatile ("standby no_wake_grant\n\t");
  38 }
  39
  40 static int nds32_pm_valid(suspend_state_t state)
  41 {
  42         switch (state) {
  43         case PM_SUSPEND_ON:
  44         case PM_SUSPEND_STANDBY:
  45         case PM_SUSPEND_MEM:
  46                 return 1;
  47         default:
  48                 return 0;
  49         }
  50 }
  51
  52 static int nds32_pm_enter(suspend_state_t state)
  53 {
  54         pr_debug("%s:state:%d\n", __func__, state);
  55         switch (state) {
  56         case PM_SUSPEND_STANDBY:
  57                 nds32_suspend_cpu();
  58                 return 0;
  59         case PM_SUSPEND_MEM:
  60                 nds32_suspend2ram();
  61                 return 0;
  62         default:
  63                 return -EINVAL;
  64         }
  65 }
  66
  67 static const struct platform_suspend_ops nds32_pm_ops = {
  68         .valid = nds32_pm_valid,
  69         .enter = nds32_pm_enter,
  70 };
  71
  72 static int __init nds32_pm_init(void)
  73 {
  74         pr_debug("Enter %s\n", __func__);
  75         suspend_set_ops(&nds32_pm_ops);
  76         return 0;
  77 }
  78 late_initcall(nds32_pm_init);