1 /*
2 * Support for power management features of the OLPC XO-1 laptop
3 *
4 * Copyright (C) 2010 Andres Salomon <dilinger@queued.net>
5 * Copyright (C) 2010 One Laptop per Child
6 * Copyright (C) 2006 Red Hat, Inc.
7 * Copyright (C) 2006 Advanced Micro Devices, Inc.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 */
14
15 #include <linux/cs5535.h>
16 #include <linux/platform_device.h>
17 #include <linux/export.h>
18 #include <linux/pm.h>
19 #include <linux/mfd/core.h>
20 #include <linux/suspend.h>
21 #include <linux/olpc-ec.h>
22
23 #include <asm/io.h>
24 #include <asm/olpc.h>
25
26 #define DRV_NAME "olpc-xo1-pm"
27
28 static unsigned long acpi_base;
29 static unsigned long pms_base;
30
31 static u16 wakeup_mask = CS5536_PM_PWRBTN;
32
33 static struct {
34 unsigned long address;
35 unsigned short segment;
36 } ofw_bios_entry = { 0xF0000 + PAGE_OFFSET, __KERNEL_CS };
37
38 /* Set bits in the wakeup mask */
olpc_xo1_pm_wakeup_set(u16 value)39 void olpc_xo1_pm_wakeup_set(u16 value)
40 {
41 wakeup_mask |= value;
42 }
43 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_set);
44
45 /* Clear bits in the wakeup mask */
olpc_xo1_pm_wakeup_clear(u16 value)46 void olpc_xo1_pm_wakeup_clear(u16 value)
47 {
48 wakeup_mask &= ~value;
49 }
50 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_clear);
51
xo1_power_state_enter(suspend_state_t pm_state)52 static int xo1_power_state_enter(suspend_state_t pm_state)
53 {
54 unsigned long saved_sci_mask;
55
56 /* Only STR is supported */
57 if (pm_state != PM_SUSPEND_MEM)
58 return -EINVAL;
59
60 /*
61 * Save SCI mask (this gets lost since PM1_EN is used as a mask for
62 * wakeup events, which is not necessarily the same event set)
63 */
64 saved_sci_mask = inl(acpi_base + CS5536_PM1_STS);
65 saved_sci_mask &= 0xffff0000;
66
67 /* Save CPU state */
68 do_olpc_suspend_lowlevel();
69
70 /* Resume path starts here */
71
72 /* Restore SCI mask (using dword access to CS5536_PM1_EN) */
73 outl(saved_sci_mask, acpi_base + CS5536_PM1_STS);
74
75 return 0;
76 }
77
xo1_do_sleep(u8 sleep_state)78 asmlinkage __visible int xo1_do_sleep(u8 sleep_state)
79 {
80 void *pgd_addr = __va(read_cr3());
81
82 /* Program wakeup mask (using dword access to CS5536_PM1_EN) */
83 outl(wakeup_mask << 16, acpi_base + CS5536_PM1_STS);
84
85 __asm__("movl %0,%%eax" : : "r" (pgd_addr));
86 __asm__("call *(%%edi); cld"
87 : : "D" (&ofw_bios_entry));
88 __asm__("movb $0x34, %al\n\t"
89 "outb %al, $0x70\n\t"
90 "movb $0x30, %al\n\t"
91 "outb %al, $0x71\n\t");
92 return 0;
93 }
94
xo1_power_off(void)95 static void xo1_power_off(void)
96 {
97 printk(KERN_INFO "OLPC XO-1 power off sequence...\n");
98
99 /* Enable all of these controls with 0 delay */
100 outl(0x40000000, pms_base + CS5536_PM_SCLK);
101 outl(0x40000000, pms_base + CS5536_PM_IN_SLPCTL);
102 outl(0x40000000, pms_base + CS5536_PM_WKXD);
103 outl(0x40000000, pms_base + CS5536_PM_WKD);
104
105 /* Clear status bits (possibly unnecessary) */
106 outl(0x0002ffff, pms_base + CS5536_PM_SSC);
107 outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
108
109 /* Write SLP_EN bit to start the machinery */
110 outl(0x00002000, acpi_base + CS5536_PM1_CNT);
111 }
112
xo1_power_state_valid(suspend_state_t pm_state)113 static int xo1_power_state_valid(suspend_state_t pm_state)
114 {
115 /* suspend-to-RAM only */
116 return pm_state == PM_SUSPEND_MEM;
117 }
118
119 static const struct platform_suspend_ops xo1_suspend_ops = {
120 .valid = xo1_power_state_valid,
121 .enter = xo1_power_state_enter,
122 };
123
xo1_pm_probe(struct platform_device * pdev)124 static int xo1_pm_probe(struct platform_device *pdev)
125 {
126 struct resource *res;
127 int err;
128
129 /* don't run on non-XOs */
130 if (!machine_is_olpc())
131 return -ENODEV;
132
133 err = mfd_cell_enable(pdev);
134 if (err)
135 return err;
136
137 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
138 if (!res) {
139 dev_err(&pdev->dev, "can't fetch device resource info\n");
140 return -EIO;
141 }
142 if (strcmp(pdev->name, "cs5535-pms") == 0)
143 pms_base = res->start;
144 else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
145 acpi_base = res->start;
146
147 /* If we have both addresses, we can override the poweroff hook */
148 if (pms_base && acpi_base) {
149 suspend_set_ops(&xo1_suspend_ops);
150 pm_power_off = xo1_power_off;
151 printk(KERN_INFO "OLPC XO-1 support registered\n");
152 }
153
154 return 0;
155 }
156
xo1_pm_remove(struct platform_device * pdev)157 static int xo1_pm_remove(struct platform_device *pdev)
158 {
159 mfd_cell_disable(pdev);
160
161 if (strcmp(pdev->name, "cs5535-pms") == 0)
162 pms_base = 0;
163 else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
164 acpi_base = 0;
165
166 pm_power_off = NULL;
167 return 0;
168 }
169
170 static struct platform_driver cs5535_pms_driver = {
171 .driver = {
172 .name = "cs5535-pms",
173 },
174 .probe = xo1_pm_probe,
175 .remove = xo1_pm_remove,
176 };
177
178 static struct platform_driver cs5535_acpi_driver = {
179 .driver = {
180 .name = "olpc-xo1-pm-acpi",
181 },
182 .probe = xo1_pm_probe,
183 .remove = xo1_pm_remove,
184 };
185
xo1_pm_init(void)186 static int __init xo1_pm_init(void)
187 {
188 int r;
189
190 r = platform_driver_register(&cs5535_pms_driver);
191 if (r)
192 return r;
193
194 r = platform_driver_register(&cs5535_acpi_driver);
195 if (r)
196 platform_driver_unregister(&cs5535_pms_driver);
197
198 return r;
199 }
200 arch_initcall(xo1_pm_init);
201