arch/x86/platform/olpc/olpc-xo1-pm.c

   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/pm.h>
  18 #include <linux/mfd/core.h>
  19 #include <linux/suspend.h>
  20
  21 #include <asm/io.h>
  22 #include <asm/olpc.h>
  23
  24 #define DRV_NAME "olpc-xo1-pm"
  25
  26 static unsigned long acpi_base;
  27 static unsigned long pms_base;
  28
  29 static u16 wakeup_mask = CS5536_PM_PWRBTN;
  30
  31 static struct {
  32         unsigned long address;
  33         unsigned short segment;
  34 } ofw_bios_entry = { 0xF0000 + PAGE_OFFSET, __KERNEL_CS };
  35
  36 /* Set bits in the wakeup mask */
  37 void olpc_xo1_pm_wakeup_set(u16 value)
  38 {
  39         wakeup_mask |= value;
  40 }
  41 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_set);
  42
  43 /* Clear bits in the wakeup mask */
  44 void olpc_xo1_pm_wakeup_clear(u16 value)
  45 {
  46         wakeup_mask &= ~value;
  47 }
  48 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_clear);
  49
  50 static int xo1_power_state_enter(suspend_state_t pm_state)
  51 {
  52         unsigned long saved_sci_mask;
  53         int r;
  54
  55         /* Only STR is supported */
  56         if (pm_state != PM_SUSPEND_MEM)
  57                 return -EINVAL;
  58
  59         r = olpc_ec_cmd(EC_SET_SCI_INHIBIT, NULL, 0, NULL, 0);
  60         if (r)
  61                 return r;
  62
  63         /*
  64          * Save SCI mask (this gets lost since PM1_EN is used as a mask for
  65          * wakeup events, which is not necessarily the same event set)
  66          */
  67         saved_sci_mask = inl(acpi_base + CS5536_PM1_STS);
  68         saved_sci_mask &= 0xffff0000;
  69
  70         /* Save CPU state */
  71         do_olpc_suspend_lowlevel();
  72
  73         /* Resume path starts here */
  74
  75         /* Restore SCI mask (using dword access to CS5536_PM1_EN) */
  76         outl(saved_sci_mask, acpi_base + CS5536_PM1_STS);
  77
  78         /* Tell the EC to stop inhibiting SCIs */
  79         olpc_ec_cmd(EC_SET_SCI_INHIBIT_RELEASE, NULL, 0, NULL, 0);
  80
  81         /*
  82          * Tell the wireless module to restart USB communication.
  83          * Must be done twice.
  84          */
  85         olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
  86         olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
  87
  88         return 0;
  89 }
  90
  91 asmlinkage int xo1_do_sleep(u8 sleep_state)
  92 {
  93         void *pgd_addr = __va(read_cr3());
  94
  95         /* Program wakeup mask (using dword access to CS5536_PM1_EN) */
  96         outl(wakeup_mask << 16, acpi_base + CS5536_PM1_STS);
  97
  98         __asm__("movl %0,%%eax" : : "r" (pgd_addr));
  99         __asm__("call *(%%edi); cld"
 100                 : : "D" (&ofw_bios_entry));
 101         __asm__("movb $0x34, %al\n\t"
 102                 "outb %al, $0x70\n\t"
 103                 "movb $0x30, %al\n\t"
 104                 "outb %al, $0x71\n\t");
 105         return 0;
 106 }
 107
 108 static void xo1_power_off(void)
 109 {
 110         printk(KERN_INFO "OLPC XO-1 power off sequence...\n");
 111
 112         /* Enable all of these controls with 0 delay */
 113         outl(0x40000000, pms_base + CS5536_PM_SCLK);
 114         outl(0x40000000, pms_base + CS5536_PM_IN_SLPCTL);
 115         outl(0x40000000, pms_base + CS5536_PM_WKXD);
 116         outl(0x40000000, pms_base + CS5536_PM_WKD);
 117
 118         /* Clear status bits (possibly unnecessary) */
 119         outl(0x0002ffff, pms_base  + CS5536_PM_SSC);
 120         outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
 121
 122         /* Write SLP_EN bit to start the machinery */
 123         outl(0x00002000, acpi_base + CS5536_PM1_CNT);
 124 }
 125
 126 static int xo1_power_state_valid(suspend_state_t pm_state)
 127 {
 128         /* suspend-to-RAM only */
 129         return pm_state == PM_SUSPEND_MEM;
 130 }
 131
 132 static const struct platform_suspend_ops xo1_suspend_ops = {
 133         .valid = xo1_power_state_valid,
 134         .enter = xo1_power_state_enter,
 135 };
 136
 137 static int __devinit xo1_pm_probe(struct platform_device *pdev)
 138 {
 139         struct resource *res;
 140         int err;
 141
 142         /* don't run on non-XOs */
 143         if (!machine_is_olpc())
 144                 return -ENODEV;
 145
 146         err = mfd_cell_enable(pdev);
 147         if (err)
 148                 return err;
 149
 150         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 151         if (!res) {
 152                 dev_err(&pdev->dev, "can't fetch device resource info\n");
 153                 return -EIO;
 154         }
 155         if (strcmp(pdev->name, "cs5535-pms") == 0)
 156                 pms_base = res->start;
 157         else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
 158                 acpi_base = res->start;
 159
 160         /* If we have both addresses, we can override the poweroff hook */
 161         if (pms_base && acpi_base) {
 162                 suspend_set_ops(&xo1_suspend_ops);
 163                 pm_power_off = xo1_power_off;
 164                 printk(KERN_INFO "OLPC XO-1 support registered\n");
 165         }
 166
 167         return 0;
 168 }
 169
 170 static int __devexit xo1_pm_remove(struct platform_device *pdev)
 171 {
 172         mfd_cell_disable(pdev);
 173
 174         if (strcmp(pdev->name, "cs5535-pms") == 0)
 175                 pms_base = 0;
 176         else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0)
 177                 acpi_base = 0;
 178
 179         pm_power_off = NULL;
 180         return 0;
 181 }
 182
 183 static struct platform_driver cs5535_pms_driver = {
 184         .driver = {
 185                 .name = "cs5535-pms",
 186                 .owner = THIS_MODULE,
 187         },
 188         .probe = xo1_pm_probe,
 189         .remove = __devexit_p(xo1_pm_remove),
 190 };
 191
 192 static struct platform_driver cs5535_acpi_driver = {
 193         .driver = {
 194                 .name = "olpc-xo1-pm-acpi",
 195                 .owner = THIS_MODULE,
 196         },
 197         .probe = xo1_pm_probe,
 198         .remove = __devexit_p(xo1_pm_remove),
 199 };
 200
 201 static int __init xo1_pm_init(void)
 202 {
 203         int r;
 204
 205         r = platform_driver_register(&cs5535_pms_driver);
 206         if (r)
 207                 return r;
 208
 209         r = platform_driver_register(&cs5535_acpi_driver);
 210         if (r)
 211                 platform_driver_unregister(&cs5535_pms_driver);
 212
 213         return r;
 214 }
 215 arch_initcall(xo1_pm_init);