1// SPDX-License-Identifier: GPL-2.0
2#include <linux/io.h>
3#include <linux/init.h>
4#include <linux/ioport.h>
5#include <linux/export.h>
6#include <linux/of.h>
7#include <linux/platform_device.h>
8
9static unsigned long acpi_iobase;
10
11#define ACPI_PM_EVT_BLK (acpi_iobase + 0x00) /* 4 bytes */
12#define ACPI_PM_CNT_BLK (acpi_iobase + 0x04) /* 2 bytes */
13#define ACPI_PMA_CNT_BLK (acpi_iobase + 0x0F) /* 1 byte */
14#define ACPI_PM_TMR_BLK (acpi_iobase + 0x18) /* 4 bytes */
15#define ACPI_GPE0_BLK (acpi_iobase + 0x10) /* 8 bytes */
16#define ACPI_END (acpi_iobase + 0x80)
17
18#define PM_INDEX 0xCD6
19#define PM_DATA 0xCD7
20#define PM2_INDEX 0xCD0
21#define PM2_DATA 0xCD1
22
23static void pmio_write_index(u16 index, u8 reg, u8 value)
24{
25 outb(value: reg, port: index);
26 outb(value, port: index + 1);
27}
28
29static u8 pmio_read_index(u16 index, u8 reg)
30{
31 outb(value: reg, port: index);
32 return inb(port: index + 1);
33}
34
35static void pm_iowrite(u8 reg, u8 value)
36{
37 pmio_write_index(PM_INDEX, reg, value);
38}
39
40static u8 pm_ioread(u8 reg)
41{
42 return pmio_read_index(PM_INDEX, reg);
43}
44
45static void pm2_iowrite(u8 reg, u8 value)
46{
47 pmio_write_index(PM2_INDEX, reg, value);
48}
49
50static u8 pm2_ioread(u8 reg)
51{
52 return pmio_read_index(PM2_INDEX, reg);
53}
54
55static void acpi_hw_clear_status(void)
56{
57 u16 value;
58
59 /* PMStatus: Clear WakeStatus/PwrBtnStatus */
60 value = inw(ACPI_PM_EVT_BLK);
61 value |= (1 << 8 | 1 << 15);
62 outw(value, ACPI_PM_EVT_BLK);
63
64 /* GPEStatus: Clear all generated events */
65 outl(inl(ACPI_GPE0_BLK), ACPI_GPE0_BLK);
66}
67
68static void acpi_registers_setup(void)
69{
70 u32 value;
71
72 /* PM Status Base */
73 pm_iowrite(reg: 0x20, ACPI_PM_EVT_BLK & 0xff);
74 pm_iowrite(reg: 0x21, ACPI_PM_EVT_BLK >> 8);
75
76 /* PM Control Base */
77 pm_iowrite(reg: 0x22, ACPI_PM_CNT_BLK & 0xff);
78 pm_iowrite(reg: 0x23, ACPI_PM_CNT_BLK >> 8);
79
80 /* GPM Base */
81 pm_iowrite(reg: 0x28, ACPI_GPE0_BLK & 0xff);
82 pm_iowrite(reg: 0x29, ACPI_GPE0_BLK >> 8);
83
84 /* ACPI End */
85 pm_iowrite(reg: 0x2e, ACPI_END & 0xff);
86 pm_iowrite(reg: 0x2f, ACPI_END >> 8);
87
88 /* IO Decode: When AcpiDecodeEnable set, South-Bridge uses the contents
89 * of the PM registers at index 0x20~0x2B to decode ACPI I/O address. */
90 pm_iowrite(reg: 0x0e, value: 1 << 3);
91
92 /* SCI_EN set */
93 outw(value: 1, ACPI_PM_CNT_BLK);
94
95 /* Enable to generate SCI */
96 pm_iowrite(reg: 0x10, value: pm_ioread(reg: 0x10) | 1);
97
98 /* GPM3/GPM9 enable */
99 value = inl(ACPI_GPE0_BLK + 4);
100 outl(value: value | (1 << 14) | (1 << 22), ACPI_GPE0_BLK + 4);
101
102 /* Set GPM9 as input */
103 pm_iowrite(reg: 0x8d, value: pm_ioread(reg: 0x8d) & (~(1 << 1)));
104
105 /* Set GPM9 as non-output */
106 pm_iowrite(reg: 0x94, value: pm_ioread(reg: 0x94) | (1 << 3));
107
108 /* GPM3 config ACPI trigger SCIOUT */
109 pm_iowrite(reg: 0x33, value: pm_ioread(reg: 0x33) & (~(3 << 4)));
110
111 /* GPM9 config ACPI trigger SCIOUT */
112 pm_iowrite(reg: 0x3d, value: pm_ioread(reg: 0x3d) & (~(3 << 2)));
113
114 /* GPM3 config falling edge trigger */
115 pm_iowrite(reg: 0x37, value: pm_ioread(reg: 0x37) & (~(1 << 6)));
116
117 /* No wait for STPGNT# in ACPI Sx state */
118 pm_iowrite(reg: 0x7c, value: pm_ioread(reg: 0x7c) | (1 << 6));
119
120 /* Set GPM3 pull-down enable */
121 value = pm2_ioread(reg: 0xf6);
122 value |= ((1 << 7) | (1 << 3));
123 pm2_iowrite(reg: 0xf6, value);
124
125 /* Set GPM9 pull-down enable */
126 value = pm2_ioread(reg: 0xf8);
127 value |= ((1 << 5) | (1 << 1));
128 pm2_iowrite(reg: 0xf8, value);
129}
130
131static int rs780e_acpi_probe(struct platform_device *pdev)
132{
133 struct resource *res;
134
135 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
136 if (!res)
137 return -ENODEV;
138
139 /* SCI interrupt need acpi space, allocate here */
140 if (!request_region(res->start, resource_size(res), "acpi")) {
141 pr_err("RS780E-ACPI: Failed to request IO Region\n");
142 return -EBUSY;
143 }
144
145 acpi_iobase = res->start;
146
147 acpi_registers_setup();
148 acpi_hw_clear_status();
149
150 return 0;
151}
152
153static const struct of_device_id rs780e_acpi_match[] = {
154 { .compatible = "loongson,rs780e-acpi" },
155 {},
156};
157
158static struct platform_driver rs780e_acpi_driver = {
159 .probe = rs780e_acpi_probe,
160 .driver = {
161 .name = "RS780E-ACPI",
162 .of_match_table = rs780e_acpi_match,
163 },
164};
165builtin_platform_driver(rs780e_acpi_driver);
166

source code of linux/drivers/platform/mips/rs780e-acpi.c