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(reg, index);
26	outb(value, index + 1);
27}
28
29static u8 pmio_read_index(u16 index, u8 reg)
30{
31	outb(reg, index);
32	return inb(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(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
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