xref: /linux/drivers/platform/mips/rs780e-acpi.c (revision eed4edda910fe34dfae8c6bfbcf57f4593a54295)
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 
9 static 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 
23 static void pmio_write_index(u16 index, u8 reg, u8 value)
24 {
25 	outb(reg, index);
26 	outb(value, index + 1);
27 }
28 
29 static u8 pmio_read_index(u16 index, u8 reg)
30 {
31 	outb(reg, index);
32 	return inb(index + 1);
33 }
34 
35 static void pm_iowrite(u8 reg, u8 value)
36 {
37 	pmio_write_index(PM_INDEX, reg, value);
38 }
39 
40 static u8 pm_ioread(u8 reg)
41 {
42 	return pmio_read_index(PM_INDEX, reg);
43 }
44 
45 static void pm2_iowrite(u8 reg, u8 value)
46 {
47 	pmio_write_index(PM2_INDEX, reg, value);
48 }
49 
50 static u8 pm2_ioread(u8 reg)
51 {
52 	return pmio_read_index(PM2_INDEX, reg);
53 }
54 
55 static 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 
68 static void acpi_registers_setup(void)
69 {
70 	u32 value;
71 
72 	/* PM Status Base */
73 	pm_iowrite(0x20, ACPI_PM_EVT_BLK & 0xff);
74 	pm_iowrite(0x21, ACPI_PM_EVT_BLK >> 8);
75 
76 	/* PM Control Base */
77 	pm_iowrite(0x22, ACPI_PM_CNT_BLK & 0xff);
78 	pm_iowrite(0x23, ACPI_PM_CNT_BLK >> 8);
79 
80 	/* GPM Base */
81 	pm_iowrite(0x28, ACPI_GPE0_BLK & 0xff);
82 	pm_iowrite(0x29, ACPI_GPE0_BLK >> 8);
83 
84 	/* ACPI End */
85 	pm_iowrite(0x2e, ACPI_END & 0xff);
86 	pm_iowrite(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(0x0e, 1 << 3);
91 
92 	/* SCI_EN set */
93 	outw(1, ACPI_PM_CNT_BLK);
94 
95 	/* Enable to generate SCI */
96 	pm_iowrite(0x10, pm_ioread(0x10) | 1);
97 
98 	/* GPM3/GPM9 enable */
99 	value = inl(ACPI_GPE0_BLK + 4);
100 	outl(value | (1 << 14) | (1 << 22), ACPI_GPE0_BLK + 4);
101 
102 	/* Set GPM9 as input */
103 	pm_iowrite(0x8d, pm_ioread(0x8d) & (~(1 << 1)));
104 
105 	/* Set GPM9 as non-output */
106 	pm_iowrite(0x94, pm_ioread(0x94) | (1 << 3));
107 
108 	/* GPM3 config ACPI trigger SCIOUT */
109 	pm_iowrite(0x33, pm_ioread(0x33) & (~(3 << 4)));
110 
111 	/* GPM9 config ACPI trigger SCIOUT */
112 	pm_iowrite(0x3d, pm_ioread(0x3d) & (~(3 << 2)));
113 
114 	/* GPM3 config falling edge trigger */
115 	pm_iowrite(0x37, pm_ioread(0x37) & (~(1 << 6)));
116 
117 	/* No wait for STPGNT# in ACPI Sx state */
118 	pm_iowrite(0x7c, pm_ioread(0x7c) | (1 << 6));
119 
120 	/* Set GPM3 pull-down enable */
121 	value = pm2_ioread(0xf6);
122 	value |= ((1 << 7) | (1 << 3));
123 	pm2_iowrite(0xf6, value);
124 
125 	/* Set GPM9 pull-down enable */
126 	value = pm2_ioread(0xf8);
127 	value |= ((1 << 5) | (1 << 1));
128 	pm2_iowrite(0xf8, value);
129 }
130 
131 static 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 
153 static const struct of_device_id rs780e_acpi_match[] = {
154 	{ .compatible = "loongson,rs780e-acpi" },
155 	{},
156 };
157 
158 static 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 };
165 builtin_platform_driver(rs780e_acpi_driver);
166