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 <dm.h>
9 #include <efi_loader.h>
10 #include <pch.h>
11 #include <sysreset.h>
12 #include <acpi/acpi_s3.h>
13 #include <asm/io.h>
14 #include <asm/processor.h>
15 #include <asm/sysreset.h>
16 
17 /*
18  * Power down the machine by using the power management sleep control
19  * of the chipset. This will currently only work on Intel chipsets.
20  * However, adapting it to new chipsets is fairly simple. You will
21  * have to find the IO address of the power management register block
22  * in your southbridge, and look up the appropriate SLP_TYP_S5 value
23  * from your southbridge's data sheet.
24  *
25  * This function never returns.
26  */
pch_sysreset_power_off(struct udevice * dev)27 int pch_sysreset_power_off(struct udevice *dev)
28 {
29 	struct x86_sysreset_plat *plat = dev_get_plat(dev);
30 	struct pch_pmbase_info pm;
31 	u32 reg32;
32 	int ret;
33 
34 	if (!plat->pch)
35 		return -ENOENT;
36 	ret = pch_ioctl(plat->pch, PCH_REQ_PMBASE_INFO, &pm, sizeof(pm));
37 	if (ret)
38 		return ret;
39 
40 	/*
41 	 * Mask interrupts or system might stay in a coma, not executing code
42 	 * anymore, but not powered off either.
43 	 */
44 	asm("cli");
45 
46 	/*
47 	 * Avoid any GPI waking the system from S5* or the system might stay in
48 	 * a coma
49 	 */
50 	outl(0x00000000, pm.base + pm.gpio0_en_ofs);
51 
52 	/* Clear Power Button Status */
53 	outw(PWRBTN_STS, pm.base + pm.pm1_sts_ofs);
54 
55 	/* PMBASE + 4, Bit 10-12, Sleeping Type, * set to 111 -> S5, soft_off */
56 	reg32 = inl(pm.base + pm.pm1_cnt_ofs);
57 
58 	/* Set Sleeping Type to S5 (poweroff) */
59 	reg32 &= ~(SLP_EN | SLP_TYP);
60 	reg32 |= SLP_TYP_S5;
61 	outl(reg32, pm.base + pm.pm1_cnt_ofs);
62 
63 	/* Now set the Sleep Enable bit */
64 	reg32 |= SLP_EN;
65 	outl(reg32, pm.base + pm.pm1_cnt_ofs);
66 
67 	for (;;)
68 		asm("hlt");
69 }
70 
x86_sysreset_request(struct udevice * dev,enum sysreset_t type)71 static int x86_sysreset_request(struct udevice *dev, enum sysreset_t type)
72 {
73 	int value;
74 	int ret;
75 
76 	switch (type) {
77 	case SYSRESET_WARM:
78 		value = SYS_RST | RST_CPU;
79 		break;
80 	case SYSRESET_COLD:
81 		value = SYS_RST | RST_CPU | FULL_RST;
82 		break;
83 	case SYSRESET_POWER_OFF:
84 		ret = pch_sysreset_power_off(dev);
85 		if (ret)
86 			return ret;
87 		return -EINPROGRESS;
88 	default:
89 		return -EPROTONOSUPPORT;
90 	}
91 
92 	outb(value, IO_PORT_RESET);
93 
94 	return -EINPROGRESS;
95 }
96 
x86_sysreset_get_last(struct udevice * dev)97 static int x86_sysreset_get_last(struct udevice *dev)
98 {
99 	return SYSRESET_POWER;
100 }
101 
102 #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)103 void __efi_runtime EFIAPI efi_reset_system(
104 			enum efi_reset_type reset_type,
105 			efi_status_t reset_status,
106 			unsigned long data_size, void *reset_data)
107 {
108 	int value;
109 
110 	/*
111 	 * inline this code since we are not caused in the context of a
112 	 * udevice and passing NULL to x86_sysreset_request() is too horrible.
113 	 */
114 	if (reset_type == EFI_RESET_COLD ||
115 		 reset_type == EFI_RESET_PLATFORM_SPECIFIC)
116 		value = SYS_RST | RST_CPU | FULL_RST;
117 	else /* assume EFI_RESET_WARM since we cannot return an error */
118 		value = SYS_RST | RST_CPU;
119 	outb(value, IO_PORT_RESET);
120 
121 	/* TODO EFI_RESET_SHUTDOWN */
122 
123 	while (1) { }
124 }
125 #endif
126 
x86_sysreset_probe(struct udevice * dev)127 static int x86_sysreset_probe(struct udevice *dev)
128 {
129 	struct x86_sysreset_plat *plat = dev_get_plat(dev);
130 
131 	/*
132 	 * Locate the PCH if there is one. It isn't essential. Avoid this before
133 	 * relocation as we shouldn't need reset then and it needs a lot of
134 	 * memory for PCI enumeration.
135 	 */
136 	if (gd->flags & GD_FLG_RELOC)
137 		uclass_first_device(UCLASS_PCH, &plat->pch);
138 
139 	return 0;
140 }
141 
142 static const struct udevice_id x86_sysreset_ids[] = {
143 	{ .compatible = "x86,reset" },
144 	{ }
145 };
146 
147 static struct sysreset_ops x86_sysreset_ops = {
148 	.request = x86_sysreset_request,
149 	.get_last = x86_sysreset_get_last,
150 };
151 
152 U_BOOT_DRIVER(x86_reset) = {
153 	.name = "x86_reset",
154 	.id = UCLASS_SYSRESET,
155 	.of_match = x86_sysreset_ids,
156 	.ops = &x86_sysreset_ops,
157 	.probe = x86_sysreset_probe,
158 	.plat_auto	= sizeof(struct x86_sysreset_plat),
159 };
160