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 void pm_iowrite(u8 reg, u8 value)
36 {
37 	pmio_write_index(PM_INDEX, reg, value);
38 }
39 EXPORT_SYMBOL(pm_iowrite);
40 
41 u8 pm_ioread(u8 reg)
42 {
43 	return pmio_read_index(PM_INDEX, reg);
44 }
45 EXPORT_SYMBOL(pm_ioread);
46 
47 void pm2_iowrite(u8 reg, u8 value)
48 {
49 	pmio_write_index(PM2_INDEX, reg, value);
50 }
51 EXPORT_SYMBOL(pm2_iowrite);
52 
53 u8 pm2_ioread(u8 reg)
54 {
55 	return pmio_read_index(PM2_INDEX, reg);
56 }
57 EXPORT_SYMBOL(pm2_ioread);
58 
59 static void acpi_hw_clear_status(void)
60 {
61 	u16 value;
62 
63 	/* PMStatus: Clear WakeStatus/PwrBtnStatus */
64 	value = inw(ACPI_PM_EVT_BLK);
65 	value |= (1 << 8 | 1 << 15);
66 	outw(value, ACPI_PM_EVT_BLK);
67 
68 	/* GPEStatus: Clear all generated events */
69 	outl(inl(ACPI_GPE0_BLK), ACPI_GPE0_BLK);
70 }
71 
72 static void acpi_registers_setup(void)
73 {
74 	u32 value;
75 
76 	/* PM Status Base */
77 	pm_iowrite(0x20, ACPI_PM_EVT_BLK & 0xff);
78 	pm_iowrite(0x21, ACPI_PM_EVT_BLK >> 8);
79 
80 	/* PM Control Base */
81 	pm_iowrite(0x22, ACPI_PM_CNT_BLK & 0xff);
82 	pm_iowrite(0x23, ACPI_PM_CNT_BLK >> 8);
83 
84 	/* GPM Base */
85 	pm_iowrite(0x28, ACPI_GPE0_BLK & 0xff);
86 	pm_iowrite(0x29, ACPI_GPE0_BLK >> 8);
87 
88 	/* ACPI End */
89 	pm_iowrite(0x2e, ACPI_END & 0xff);
90 	pm_iowrite(0x2f, ACPI_END >> 8);
91 
92 	/* IO Decode: When AcpiDecodeEnable set, South-Bridge uses the contents
93 	 * of the PM registers at index 0x20~0x2B to decode ACPI I/O address. */
94 	pm_iowrite(0x0e, 1 << 3);
95 
96 	/* SCI_EN set */
97 	outw(1, ACPI_PM_CNT_BLK);
98 
99 	/* Enable to generate SCI */
100 	pm_iowrite(0x10, pm_ioread(0x10) | 1);
101 
102 	/* GPM3/GPM9 enable */
103 	value = inl(ACPI_GPE0_BLK + 4);
104 	outl(value | (1 << 14) | (1 << 22), ACPI_GPE0_BLK + 4);
105 
106 	/* Set GPM9 as input */
107 	pm_iowrite(0x8d, pm_ioread(0x8d) & (~(1 << 1)));
108 
109 	/* Set GPM9 as non-output */
110 	pm_iowrite(0x94, pm_ioread(0x94) | (1 << 3));
111 
112 	/* GPM3 config ACPI trigger SCIOUT */
113 	pm_iowrite(0x33, pm_ioread(0x33) & (~(3 << 4)));
114 
115 	/* GPM9 config ACPI trigger SCIOUT */
116 	pm_iowrite(0x3d, pm_ioread(0x3d) & (~(3 << 2)));
117 
118 	/* GPM3 config falling edge trigger */
119 	pm_iowrite(0x37, pm_ioread(0x37) & (~(1 << 6)));
120 
121 	/* No wait for STPGNT# in ACPI Sx state */
122 	pm_iowrite(0x7c, pm_ioread(0x7c) | (1 << 6));
123 
124 	/* Set GPM3 pull-down enable */
125 	value = pm2_ioread(0xf6);
126 	value |= ((1 << 7) | (1 << 3));
127 	pm2_iowrite(0xf6, value);
128 
129 	/* Set GPM9 pull-down enable */
130 	value = pm2_ioread(0xf8);
131 	value |= ((1 << 5) | (1 << 1));
132 	pm2_iowrite(0xf8, value);
133 }
134 
135 static int rs780e_acpi_probe(struct platform_device *pdev)
136 {
137 	struct resource *res;
138 
139 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
140 	if (!res)
141 		return -ENODEV;
142 
143 	/* SCI interrupt need acpi space, allocate here */
144 	if (!request_region(res->start, resource_size(res), "acpi")) {
145 		pr_err("RS780E-ACPI: Failed to request IO Region\n");
146 		return -EBUSY;
147 	}
148 
149 	acpi_iobase = res->start;
150 
151 	acpi_registers_setup();
152 	acpi_hw_clear_status();
153 
154 	return 0;
155 }
156 
157 static const struct of_device_id rs780e_acpi_match[] = {
158 	{ .compatible = "loongson,rs780e-acpi" },
159 	{},
160 };
161 
162 static struct platform_driver rs780e_acpi_driver = {
163 	.probe = rs780e_acpi_probe,
164 	.driver = {
165 		.name = "RS780E-ACPI",
166 		.of_match_table = rs780e_acpi_match,
167 	},
168 };
169 builtin_platform_driver(rs780e_acpi_driver);
170