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 */ 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 */ 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 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 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 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 } 112 113 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 }; 123 124 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 } 156 157 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 .owner = THIS_MODULE, 174 }, 175 .probe = xo1_pm_probe, 176 .remove = xo1_pm_remove, 177 }; 178 179 static struct platform_driver cs5535_acpi_driver = { 180 .driver = { 181 .name = "olpc-xo1-pm-acpi", 182 .owner = THIS_MODULE, 183 }, 184 .probe = xo1_pm_probe, 185 .remove = xo1_pm_remove, 186 }; 187 188 static int __init xo1_pm_init(void) 189 { 190 int r; 191 192 r = platform_driver_register(&cs5535_pms_driver); 193 if (r) 194 return r; 195 196 r = platform_driver_register(&cs5535_acpi_driver); 197 if (r) 198 platform_driver_unregister(&cs5535_pms_driver); 199 200 return r; 201 } 202 arch_initcall(xo1_pm_init); 203