1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Support for power management features of the OLPC XO-1 laptop |
4 | * |
5 | * Copyright (C) 2010 Andres Salomon <dilinger@queued.net> |
6 | * Copyright (C) 2010 One Laptop per Child |
7 | * Copyright (C) 2006 Red Hat, Inc. |
8 | * Copyright (C) 2006 Advanced Micro Devices, Inc. |
9 | */ |
10 | |
11 | #include <linux/cs5535.h> |
12 | #include <linux/platform_device.h> |
13 | #include <linux/export.h> |
14 | #include <linux/pm.h> |
15 | #include <linux/suspend.h> |
16 | #include <linux/olpc-ec.h> |
17 | |
18 | #include <asm/io.h> |
19 | #include <asm/olpc.h> |
20 | |
21 | #define DRV_NAME "olpc-xo1-pm" |
22 | |
23 | static unsigned long acpi_base; |
24 | static unsigned long pms_base; |
25 | |
26 | static u16 wakeup_mask = CS5536_PM_PWRBTN; |
27 | |
28 | static struct { |
29 | unsigned long address; |
30 | unsigned short segment; |
31 | } ofw_bios_entry = { 0xF0000 + PAGE_OFFSET, __KERNEL_CS }; |
32 | |
33 | /* Set bits in the wakeup mask */ |
34 | void olpc_xo1_pm_wakeup_set(u16 value) |
35 | { |
36 | wakeup_mask |= value; |
37 | } |
38 | EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_set); |
39 | |
40 | /* Clear bits in the wakeup mask */ |
41 | void olpc_xo1_pm_wakeup_clear(u16 value) |
42 | { |
43 | wakeup_mask &= ~value; |
44 | } |
45 | EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_clear); |
46 | |
47 | static int xo1_power_state_enter(suspend_state_t pm_state) |
48 | { |
49 | unsigned long saved_sci_mask; |
50 | |
51 | /* Only STR is supported */ |
52 | if (pm_state != PM_SUSPEND_MEM) |
53 | return -EINVAL; |
54 | |
55 | /* |
56 | * Save SCI mask (this gets lost since PM1_EN is used as a mask for |
57 | * wakeup events, which is not necessarily the same event set) |
58 | */ |
59 | saved_sci_mask = inl(port: acpi_base + CS5536_PM1_STS); |
60 | saved_sci_mask &= 0xffff0000; |
61 | |
62 | /* Save CPU state */ |
63 | do_olpc_suspend_lowlevel(); |
64 | |
65 | /* Resume path starts here */ |
66 | |
67 | /* Restore SCI mask (using dword access to CS5536_PM1_EN) */ |
68 | outl(value: saved_sci_mask, port: acpi_base + CS5536_PM1_STS); |
69 | |
70 | return 0; |
71 | } |
72 | |
73 | asmlinkage __visible int xo1_do_sleep(u8 sleep_state) |
74 | { |
75 | void *pgd_addr = __va(read_cr3_pa()); |
76 | |
77 | /* Program wakeup mask (using dword access to CS5536_PM1_EN) */ |
78 | outl(value: wakeup_mask << 16, port: acpi_base + CS5536_PM1_STS); |
79 | |
80 | __asm__("movl %0,%%eax" : : "r" (pgd_addr)); |
81 | __asm__("call *(%%edi); cld" |
82 | : : "D" (&ofw_bios_entry)); |
83 | __asm__("movb $0x34, %al\n\t" |
84 | "outb %al, $0x70\n\t" |
85 | "movb $0x30, %al\n\t" |
86 | "outb %al, $0x71\n\t" ); |
87 | return 0; |
88 | } |
89 | |
90 | static void xo1_power_off(void) |
91 | { |
92 | printk(KERN_INFO "OLPC XO-1 power off sequence...\n" ); |
93 | |
94 | /* Enable all of these controls with 0 delay */ |
95 | outl(value: 0x40000000, port: pms_base + CS5536_PM_SCLK); |
96 | outl(value: 0x40000000, port: pms_base + CS5536_PM_IN_SLPCTL); |
97 | outl(value: 0x40000000, port: pms_base + CS5536_PM_WKXD); |
98 | outl(value: 0x40000000, port: pms_base + CS5536_PM_WKD); |
99 | |
100 | /* Clear status bits (possibly unnecessary) */ |
101 | outl(value: 0x0002ffff, port: pms_base + CS5536_PM_SSC); |
102 | outl(value: 0xffffffff, port: acpi_base + CS5536_PM_GPE0_STS); |
103 | |
104 | /* Write SLP_EN bit to start the machinery */ |
105 | outl(value: 0x00002000, port: acpi_base + CS5536_PM1_CNT); |
106 | } |
107 | |
108 | static int xo1_power_state_valid(suspend_state_t pm_state) |
109 | { |
110 | /* suspend-to-RAM only */ |
111 | return pm_state == PM_SUSPEND_MEM; |
112 | } |
113 | |
114 | static const struct platform_suspend_ops xo1_suspend_ops = { |
115 | .valid = xo1_power_state_valid, |
116 | .enter = xo1_power_state_enter, |
117 | }; |
118 | |
119 | static int xo1_pm_probe(struct platform_device *pdev) |
120 | { |
121 | struct resource *res; |
122 | |
123 | /* don't run on non-XOs */ |
124 | if (!machine_is_olpc()) |
125 | return -ENODEV; |
126 | |
127 | res = platform_get_resource(pdev, IORESOURCE_IO, 0); |
128 | if (!res) { |
129 | dev_err(&pdev->dev, "can't fetch device resource info\n" ); |
130 | return -EIO; |
131 | } |
132 | if (strcmp(pdev->name, "cs5535-pms" ) == 0) |
133 | pms_base = res->start; |
134 | else if (strcmp(pdev->name, "olpc-xo1-pm-acpi" ) == 0) |
135 | acpi_base = res->start; |
136 | |
137 | /* If we have both addresses, we can override the poweroff hook */ |
138 | if (pms_base && acpi_base) { |
139 | suspend_set_ops(ops: &xo1_suspend_ops); |
140 | pm_power_off = xo1_power_off; |
141 | printk(KERN_INFO "OLPC XO-1 support registered\n" ); |
142 | } |
143 | |
144 | return 0; |
145 | } |
146 | |
147 | static int xo1_pm_remove(struct platform_device *pdev) |
148 | { |
149 | if (strcmp(pdev->name, "cs5535-pms" ) == 0) |
150 | pms_base = 0; |
151 | else if (strcmp(pdev->name, "olpc-xo1-pm-acpi" ) == 0) |
152 | acpi_base = 0; |
153 | |
154 | pm_power_off = NULL; |
155 | return 0; |
156 | } |
157 | |
158 | static struct platform_driver cs5535_pms_driver = { |
159 | .driver = { |
160 | .name = "cs5535-pms" , |
161 | }, |
162 | .probe = xo1_pm_probe, |
163 | .remove = xo1_pm_remove, |
164 | }; |
165 | |
166 | static struct platform_driver cs5535_acpi_driver = { |
167 | .driver = { |
168 | .name = "olpc-xo1-pm-acpi" , |
169 | }, |
170 | .probe = xo1_pm_probe, |
171 | .remove = xo1_pm_remove, |
172 | }; |
173 | |
174 | static int __init xo1_pm_init(void) |
175 | { |
176 | int r; |
177 | |
178 | r = platform_driver_register(&cs5535_pms_driver); |
179 | if (r) |
180 | return r; |
181 | |
182 | r = platform_driver_register(&cs5535_acpi_driver); |
183 | if (r) |
184 | platform_driver_unregister(&cs5535_pms_driver); |
185 | |
186 | return r; |
187 | } |
188 | arch_initcall(xo1_pm_init); |
189 | |