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         p4d_t *p4dv;
  18         pud_t *pudv;
  19         pmd_t *pmdv;
  20         pte_t *ptev;
  21
  22         pgdv = (pgd_t *)__va((__nds32__mfsr(NDS32_SR_L1_PPTB) &
  23                 L1_PPTB_mskBASE)) + pgd_index((unsigned int)cpu_resume);
  24
  25         p4dv = p4d_offset(pgdv, (unsigned int)cpu_resume);
  26         pudv = pud_offset(p4dv, (unsigned int)cpu_resume);
  27         pmdv = pmd_offset(pudv, (unsigned int)cpu_resume);
  28         ptev = pte_offset_map(pmdv, (unsigned int)cpu_resume);
  29
  30         resume_addr = ((*ptev) & TLB_DATA_mskPPN)
  31                         | ((unsigned int)cpu_resume & 0x00000fff);
  32
  33         suspend2ram();
  34 }
  35
  36 static void nds32_suspend_cpu(void)
  37 {
  38         while (!(__nds32__mfsr(NDS32_SR_INT_PEND) & wake_mask))
  39                 __asm__ volatile ("standby no_wake_grant\n\t");
  40 }
  41
  42 static int nds32_pm_valid(suspend_state_t state)
  43 {
  44         switch (state) {
  45         case PM_SUSPEND_ON:
  46         case PM_SUSPEND_STANDBY:
  47         case PM_SUSPEND_MEM:
  48                 return 1;
  49         default:
  50                 return 0;
  51         }
  52 }
  53
  54 static int nds32_pm_enter(suspend_state_t state)
  55 {
  56         pr_debug("%s:state:%d\n", __func__, state);
  57         switch (state) {
  58         case PM_SUSPEND_STANDBY:
  59                 nds32_suspend_cpu();
  60                 return 0;
  61         case PM_SUSPEND_MEM:
  62                 nds32_suspend2ram();
  63                 return 0;
  64         default:
  65                 return -EINVAL;
  66         }
  67 }
  68
  69 static const struct platform_suspend_ops nds32_pm_ops = {
  70         .valid = nds32_pm_valid,
  71         .enter = nds32_pm_enter,
  72 };
  73
  74 static int __init nds32_pm_init(void)
  75 {
  76         pr_debug("Enter %s\n", __func__);
  77         suspend_set_ops(&nds32_pm_ops);
  78         return 0;
  79 }
  80 late_initcall(nds32_pm_init);