1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
4  *
5  * Generic reset driver for x86 processor
6  */
7 
8 #include <common.h>
9 #include <dm.h>
10 #include <efi_loader.h>
11 #include <pch.h>
12 #include <sysreset.h>
13 #include <acpi/acpi_s3.h>
14 #include <asm/io.h>
15 #include <asm/processor.h>
16 #include <asm/sysreset.h>
17 
18 /*
19  * Power down the machine by using the power management sleep control
20  * of the chipset. This will currently only work on Intel chipsets.
21  * However, adapting it to new chipsets is fairly simple. You will
22  * have to find the IO address of the power management register block
23  * in your southbridge, and look up the appropriate SLP_TYP_S5 value
24  * from your southbridge's data sheet.
25  *
26  * This function never returns.
27  */
pch_sysreset_power_off(struct udevice * dev)28 int pch_sysreset_power_off(struct udevice *dev)
29 {
30 	struct x86_sysreset_plat *plat = dev_get_plat(dev);
31 	struct pch_pmbase_info pm;
32 	u32 reg32;
33 	int ret;
34 
35 	if (!plat->pch)
36 		return -ENOENT;
37 	ret = pch_ioctl(plat->pch, PCH_REQ_PMBASE_INFO, &pm, sizeof(pm));
38 	if (ret)
39 		return ret;
40 
41 	/*
42 	 * Mask interrupts or system might stay in a coma, not executing code
43 	 * anymore, but not powered off either.
44 	 */
45 	asm("cli");
46 
47 	/*
48 	 * Avoid any GPI waking the system from S5* or the system might stay in
49 	 * a coma
50 	 */
51 	outl(0x00000000, pm.base + pm.gpio0_en_ofs);
52 
53 	/* Clear Power Button Status */
54 	outw(PWRBTN_STS, pm.base + pm.pm1_sts_ofs);
55 
56 	/* PMBASE + 4, Bit 10-12, Sleeping Type, * set to 111 -> S5, soft_off */
57 	reg32 = inl(pm.base + pm.pm1_cnt_ofs);
58 
59 	/* Set Sleeping Type to S5 (poweroff) */
60 	reg32 &= ~(SLP_EN | SLP_TYP);
61 	reg32 |= SLP_TYP_S5;
62 	outl(reg32, pm.base + pm.pm1_cnt_ofs);
63 
64 	/* Now set the Sleep Enable bit */
65 	reg32 |= SLP_EN;
66 	outl(reg32, pm.base + pm.pm1_cnt_ofs);
67 
68 	for (;;)
69 		asm("hlt");
70 }
71 
x86_sysreset_request(struct udevice * dev,enum sysreset_t type)72 static int x86_sysreset_request(struct udevice *dev, enum sysreset_t type)
73 {
74 	int value;
75 	int ret;
76 
77 	switch (type) {
78 	case SYSRESET_WARM:
79 		value = SYS_RST | RST_CPU;
80 		break;
81 	case SYSRESET_COLD:
82 		value = SYS_RST | RST_CPU | FULL_RST;
83 		break;
84 	case SYSRESET_POWER_OFF:
85 		ret = pch_sysreset_power_off(dev);
86 		if (ret)
87 			return ret;
88 		return -EINPROGRESS;
89 	default:
90 		return -ENOSYS;
91 	}
92 
93 	outb(value, IO_PORT_RESET);
94 
95 	return -EINPROGRESS;
96 }
97 
x86_sysreset_get_last(struct udevice * dev)98 static int x86_sysreset_get_last(struct udevice *dev)
99 {
100 	return SYSRESET_POWER;
101 }
102 
103 #ifdef CONFIG_EFI_LOADER
efi_reset_system(enum efi_reset_type reset_type,efi_status_t reset_status,unsigned long data_size,void * reset_data)104 void __efi_runtime EFIAPI efi_reset_system(
105 			enum efi_reset_type reset_type,
106 			efi_status_t reset_status,
107 			unsigned long data_size, void *reset_data)
108 {
109 	int value;
110 
111 	/*
112 	 * inline this code since we are not caused in the context of a
113 	 * udevice and passing NULL to x86_sysreset_request() is too horrible.
114 	 */
115 	if (reset_type == EFI_RESET_COLD ||
116 		 reset_type == EFI_RESET_PLATFORM_SPECIFIC)
117 		value = SYS_RST | RST_CPU | FULL_RST;
118 	else /* assume EFI_RESET_WARM since we cannot return an error */
119 		value = SYS_RST | RST_CPU;
120 	outb(value, IO_PORT_RESET);
121 
122 	/* TODO EFI_RESET_SHUTDOWN */
123 
124 	while (1) { }
125 }
126 #endif
127 
x86_sysreset_probe(struct udevice * dev)128 static int x86_sysreset_probe(struct udevice *dev)
129 {
130 	struct x86_sysreset_plat *plat = dev_get_plat(dev);
131 
132 	/* Locate the PCH if there is one. It isn't essential */
133 	uclass_first_device(UCLASS_PCH, &plat->pch);
134 
135 	return 0;
136 }
137 
138 static const struct udevice_id x86_sysreset_ids[] = {
139 	{ .compatible = "x86,reset" },
140 	{ }
141 };
142 
143 static struct sysreset_ops x86_sysreset_ops = {
144 	.request = x86_sysreset_request,
145 	.get_last = x86_sysreset_get_last,
146 };
147 
148 U_BOOT_DRIVER(x86_reset) = {
149 	.name = "x86_reset",
150 	.id = UCLASS_SYSRESET,
151 	.of_match = x86_sysreset_ids,
152 	.ops = &x86_sysreset_ops,
153 	.probe = x86_sysreset_probe,
154 	.plat_auto	= sizeof(struct x86_sysreset_plat),
155 };
156