arch/loongarch/power/suspend.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * loongson-specific suspend support
   4  *
   5  * Author: Huacai Chen <chenhuacai@loongson.cn>
   6  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
   7  */
   8 #include <linux/acpi.h>
   9 #include <linux/pm.h>
  10 #include <linux/suspend.h>
  11
  12 #include <asm/loongarch.h>
  13 #include <asm/loongson.h>
  14 #include <asm/setup.h>
  15 #include <asm/time.h>
  16 #include <asm/tlbflush.h>
  17
  18 u64 loongarch_suspend_addr;
  19
  20 struct saved_registers {
  21         u32 ecfg;
  22         u32 euen;
  23         u64 pgd;
  24         u64 kpgd;
  25         u32 pwctl0;
  26         u32 pwctl1;
  27 };
  28 static struct saved_registers saved_regs;
  29
  30 void loongarch_common_suspend(void)
  31 {
  32         save_counter();
  33         saved_regs.pgd = csr_read64(LOONGARCH_CSR_PGDL);
  34         saved_regs.kpgd = csr_read64(LOONGARCH_CSR_PGDH);
  35         saved_regs.pwctl0 = csr_read32(LOONGARCH_CSR_PWCTL0);
  36         saved_regs.pwctl1 = csr_read32(LOONGARCH_CSR_PWCTL1);
  37         saved_regs.ecfg = csr_read32(LOONGARCH_CSR_ECFG);
  38         saved_regs.euen = csr_read32(LOONGARCH_CSR_EUEN);
  39
  40         loongarch_suspend_addr = loongson_sysconf.suspend_addr;
  41 }
  42
  43 void loongarch_common_resume(void)
  44 {
  45         sync_counter();
  46         local_flush_tlb_all();
  47         csr_write64(per_cpu_offset(0), PERCPU_BASE_KS);
  48         csr_write64(eentry, LOONGARCH_CSR_EENTRY);
  49         csr_write64(eentry, LOONGARCH_CSR_MERRENTRY);
  50         csr_write64(tlbrentry, LOONGARCH_CSR_TLBRENTRY);
  51
  52         csr_write64(saved_regs.pgd, LOONGARCH_CSR_PGDL);
  53         csr_write64(saved_regs.kpgd, LOONGARCH_CSR_PGDH);
  54         csr_write32(saved_regs.pwctl0, LOONGARCH_CSR_PWCTL0);
  55         csr_write32(saved_regs.pwctl1, LOONGARCH_CSR_PWCTL1);
  56         csr_write32(saved_regs.ecfg, LOONGARCH_CSR_ECFG);
  57         csr_write32(saved_regs.euen, LOONGARCH_CSR_EUEN);
  58 }
  59
  60 int loongarch_acpi_suspend(void)
  61 {
  62         enable_gpe_wakeup();
  63         enable_pci_wakeup();
  64
  65         loongarch_common_suspend();
  66
  67         /* processor specific suspend */
  68         loongarch_suspend_enter();
  69
  70         loongarch_common_resume();
  71
  72         return 0;
  73 }