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(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(saved_sci_mask, 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(wakeup_mask << 16, 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(0x40000000, pms_base + CS5536_PM_SCLK); 96 outl(0x40000000, pms_base + CS5536_PM_IN_SLPCTL); 97 outl(0x40000000, pms_base + CS5536_PM_WKXD); 98 outl(0x40000000, pms_base + CS5536_PM_WKD); 99 100 /* Clear status bits (possibly unnecessary) */ 101 outl(0x0002ffff, pms_base + CS5536_PM_SSC); 102 outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS); 103 104 /* Write SLP_EN bit to start the machinery */ 105 outl(0x00002000, 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(&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