xref: /linux/arch/loongarch/power/suspend.c (revision f2527d8f566a45fa00ee5abd04d1c9476d4d704f)
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 static void arch_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 static void arch_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 	arch_common_suspend();
66 
67 	/* processor specific suspend */
68 	loongarch_suspend_enter();
69 
70 	arch_common_resume();
71 
72 	return 0;
73 }
74