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
22 #include <asm/io.h>
23 #include <asm/olpc.h>
24
25 #define DRV_NAME "olpc-xo1-pm"
26
27 static unsigned long acpi_base;
28 static unsigned long pms_base;
29
30 static u16 wakeup_mask = CS5536_PM_PWRBTN;
31
32 static struct {
33 unsigned long address;
34 unsigned short segment;
35 } ofw_bios_entry = { 0xF0000 + PAGE_OFFSET, __KERNEL_CS };
36
37 /* Set bits in the wakeup mask */
olpc_xo1_pm_wakeup_set(u16 value)38 void olpc_xo1_pm_wakeup_set(u16 value)
39 {
40 wakeup_mask |= value;
41 }
42 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_set);
43
44 /* Clear bits in the wakeup mask */
olpc_xo1_pm_wakeup_clear(u16 value)45 void olpc_xo1_pm_wakeup_clear(u16 value)
46 {
47 wakeup_mask &= ~value;
48 }
49 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_clear);
50
xo1_power_state_enter(suspend_state_t pm_state)51 static int xo1_power_state_enter(suspend_state_t pm_state)
52 {
53 unsigned long saved_sci_mask;
54 int r;
55
56 /* Only STR is supported */
57 if (pm_state != PM_SUSPEND_MEM)
58 return -EINVAL;
59
60 r = olpc_ec_cmd(EC_SET_SCI_INHIBIT, NULL, 0, NULL, 0);
61 if (r)
62 return r;
63
64 /*
65 * Save SCI mask (this gets lost since PM1_EN is used as a mask for
66 * wakeup events, which is not necessarily the same event set)
67 */
68 saved_sci_mask = inl(acpi_base + CS5536_PM1_STS);
69 saved_sci_mask &= 0xffff0000;
70
71 /* Save CPU state */
72 do_olpc_suspend_lowlevel();
73
74 /* Resume path starts here */
75
76 /* Restore SCI mask (using dword access to CS5536_PM1_EN) */
77 outl(saved_sci_mask, acpi_base + CS5536_PM1_STS);
78
79 /* Tell the EC to stop inhibiting SCIs */
80 olpc_ec_cmd(EC_SET_SCI_INHIBIT_RELEASE, NULL, 0, NULL, 0);
81
82 /*
83 * Tell the wireless module to restart USB communication.
84 * Must be done twice.
85 */
86 olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
87 olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
88
89 return 0;
90 }
91
xo1_do_sleep(u8 sleep_state)92 asmlinkage int xo1_do_sleep(u8 sleep_state)
93 {
94 void *pgd_addr = __va(read_cr3());
95
96 /* Program wakeup mask (using dword access to CS5536_PM1_EN) */
97 outl(wakeup_mask << 16, acpi_base + CS5536_PM1_STS);
98
99 __asm__("movl %0,%%eax" : : "r" (pgd_addr));
100 __asm__("call *(%%edi); cld"
101 : : "D" (&ofw_bios_entry));
102 __asm__("movb $0x34, %al\n\t"
103 "outb %al, $0x70\n\t"
104 "movb $0x30, %al\n\t"
105 "outb %al, $0x71\n\t");
106 return 0;
107 }
108
xo1_power_off(void)109 static void xo1_power_off(void)
110 {
111 printk(KERN_INFO "OLPC XO-1 power off sequence...\n");
112
113 /* Enable all of these controls with 0 delay */
114 outl(0x40000000, pms_base + CS5536_PM_SCLK);
115 outl(0x40000000, pms_base + CS5536_PM_IN_SLPCTL);
116 outl(0x40000000, pms_base + CS5536_PM_WKXD);
117 outl(0x40000000, pms_base + CS5536_PM_WKD);
118
119 /* Clear status bits (possibly unnecessary) */
120 outl(0x0002ffff, pms_base + CS5536_PM_SSC);
121 outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
122
123 /* Write SLP_EN bit to start the machinery */
124 outl(0x00002000, acpi_base + CS5536_PM1_CNT);
125 }
126
xo1_power_state_valid(suspend_state_t pm_state)127 static int xo1_power_state_valid(suspend_state_t pm_state)
128 {
129 /* suspend-to-RAM only */
130 return pm_state == PM_SUSPEND_MEM;
131 }
132
133 static const struct platform_suspend_ops xo1_suspend_ops = {
134 .valid = xo1_power_state_valid,
135 .enter = xo1_power_state_enter,
136 };
137
xo1_pm_probe(struct platform_device * pdev)138 static int __devinit xo1_pm_probe(struct platform_device *pdev)
139 {
140 struct resource *res;
141 int err;
142
143 /* don't run on non-XOs */
144 if (!machine_is_olpc())
145 return -ENODEV;
146
147 err = mfd_cell_enable(pdev);
148 if (err)
149 return err;
150
151 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
152 if (!res) {
153 dev_err(&pdev->dev, "can't fetch device resource info\n");
154 return -EIO;
155 }
156 if (strcmp(pdev->name, "cs5535-pms") == 0)
157 pms_base = res->start;
158 else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
159 acpi_base = res->start;
160
161 /* If we have both addresses, we can override the poweroff hook */
162 if (pms_base && acpi_base) {
163 suspend_set_ops(&xo1_suspend_ops);
164 pm_power_off = xo1_power_off;
165 printk(KERN_INFO "OLPC XO-1 support registered\n");
166 }
167
168 return 0;
169 }
170
xo1_pm_remove(struct platform_device * pdev)171 static int __devexit xo1_pm_remove(struct platform_device *pdev)
172 {
173 mfd_cell_disable(pdev);
174
175 if (strcmp(pdev->name, "cs5535-pms") == 0)
176 pms_base = 0;
177 else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
178 acpi_base = 0;
179
180 pm_power_off = NULL;
181 return 0;
182 }
183
184 static struct platform_driver cs5535_pms_driver = {
185 .driver = {
186 .name = "cs5535-pms",
187 .owner = THIS_MODULE,
188 },
189 .probe = xo1_pm_probe,
190 .remove = __devexit_p(xo1_pm_remove),
191 };
192
193 static struct platform_driver cs5535_acpi_driver = {
194 .driver = {
195 .name = "olpc-xo1-pm-acpi",
196 .owner = THIS_MODULE,
197 },
198 .probe = xo1_pm_probe,
199 .remove = __devexit_p(xo1_pm_remove),
200 };
201
xo1_pm_init(void)202 static int __init xo1_pm_init(void)
203 {
204 int r;
205
206 r = platform_driver_register(&cs5535_pms_driver);
207 if (r)
208 return r;
209
210 r = platform_driver_register(&cs5535_acpi_driver);
211 if (r)
212 platform_driver_unregister(&cs5535_pms_driver);
213
214 return r;
215 }
216 arch_initcall(xo1_pm_init);
217