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/mfd/core.h> 16 #include <linux/suspend.h> 17 #include <linux/olpc-ec.h> 18 19 #include <asm/io.h> 20 #include <asm/olpc.h> 21 22 #define DRV_NAME "olpc-xo1-pm" 23 24 static unsigned long acpi_base; 25 static unsigned long pms_base; 26 27 static u16 wakeup_mask = CS5536_PM_PWRBTN; 28 29 static struct { 30 unsigned long address; 31 unsigned short segment; 32 } ofw_bios_entry = { 0xF0000 + PAGE_OFFSET, __KERNEL_CS }; 33 34 /* Set bits in the wakeup mask */ 35 void olpc_xo1_pm_wakeup_set(u16 value) 36 { 37 wakeup_mask |= value; 38 } 39 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_set); 40 41 /* Clear bits in the wakeup mask */ 42 void olpc_xo1_pm_wakeup_clear(u16 value) 43 { 44 wakeup_mask &= ~value; 45 } 46 EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_clear); 47 48 static int xo1_power_state_enter(suspend_state_t pm_state) 49 { 50 unsigned long saved_sci_mask; 51 52 /* Only STR is supported */ 53 if (pm_state != PM_SUSPEND_MEM) 54 return -EINVAL; 55 56 /* 57 * Save SCI mask (this gets lost since PM1_EN is used as a mask for 58 * wakeup events, which is not necessarily the same event set) 59 */ 60 saved_sci_mask = inl(acpi_base + CS5536_PM1_STS); 61 saved_sci_mask &= 0xffff0000; 62 63 /* Save CPU state */ 64 do_olpc_suspend_lowlevel(); 65 66 /* Resume path starts here */ 67 68 /* Restore SCI mask (using dword access to CS5536_PM1_EN) */ 69 outl(saved_sci_mask, acpi_base + CS5536_PM1_STS); 70 71 return 0; 72 } 73 74 asmlinkage __visible int xo1_do_sleep(u8 sleep_state) 75 { 76 void *pgd_addr = __va(read_cr3_pa()); 77 78 /* Program wakeup mask (using dword access to CS5536_PM1_EN) */ 79 outl(wakeup_mask << 16, acpi_base + CS5536_PM1_STS); 80 81 __asm__("movl %0,%%eax" : : "r" (pgd_addr)); 82 __asm__("call *(%%edi); cld" 83 : : "D" (&ofw_bios_entry)); 84 __asm__("movb $0x34, %al\n\t" 85 "outb %al, $0x70\n\t" 86 "movb $0x30, %al\n\t" 87 "outb %al, $0x71\n\t"); 88 return 0; 89 } 90 91 static void xo1_power_off(void) 92 { 93 printk(KERN_INFO "OLPC XO-1 power off sequence...\n"); 94 95 /* Enable all of these controls with 0 delay */ 96 outl(0x40000000, pms_base + CS5536_PM_SCLK); 97 outl(0x40000000, pms_base + CS5536_PM_IN_SLPCTL); 98 outl(0x40000000, pms_base + CS5536_PM_WKXD); 99 outl(0x40000000, pms_base + CS5536_PM_WKD); 100 101 /* Clear status bits (possibly unnecessary) */ 102 outl(0x0002ffff, pms_base + CS5536_PM_SSC); 103 outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS); 104 105 /* Write SLP_EN bit to start the machinery */ 106 outl(0x00002000, acpi_base + CS5536_PM1_CNT); 107 } 108 109 static int xo1_power_state_valid(suspend_state_t pm_state) 110 { 111 /* suspend-to-RAM only */ 112 return pm_state == PM_SUSPEND_MEM; 113 } 114 115 static const struct platform_suspend_ops xo1_suspend_ops = { 116 .valid = xo1_power_state_valid, 117 .enter = xo1_power_state_enter, 118 }; 119 120 static int xo1_pm_probe(struct platform_device *pdev) 121 { 122 struct resource *res; 123 int err; 124 125 /* don't run on non-XOs */ 126 if (!machine_is_olpc()) 127 return -ENODEV; 128 129 err = mfd_cell_enable(pdev); 130 if (err) 131 return err; 132 133 res = platform_get_resource(pdev, IORESOURCE_IO, 0); 134 if (!res) { 135 dev_err(&pdev->dev, "can't fetch device resource info\n"); 136 return -EIO; 137 } 138 if (strcmp(pdev->name, "cs5535-pms") == 0) 139 pms_base = res->start; 140 else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0) 141 acpi_base = res->start; 142 143 /* If we have both addresses, we can override the poweroff hook */ 144 if (pms_base && acpi_base) { 145 suspend_set_ops(&xo1_suspend_ops); 146 pm_power_off = xo1_power_off; 147 printk(KERN_INFO "OLPC XO-1 support registered\n"); 148 } 149 150 return 0; 151 } 152 153 static int xo1_pm_remove(struct platform_device *pdev) 154 { 155 mfd_cell_disable(pdev); 156 157 if (strcmp(pdev->name, "cs5535-pms") == 0) 158 pms_base = 0; 159 else if (strcmp(pdev->name, "olpc-xo1-pm-acpi") == 0) 160 acpi_base = 0; 161 162 pm_power_off = NULL; 163 return 0; 164 } 165 166 static struct platform_driver cs5535_pms_driver = { 167 .driver = { 168 .name = "cs5535-pms", 169 }, 170 .probe = xo1_pm_probe, 171 .remove = xo1_pm_remove, 172 }; 173 174 static struct platform_driver cs5535_acpi_driver = { 175 .driver = { 176 .name = "olpc-xo1-pm-acpi", 177 }, 178 .probe = xo1_pm_probe, 179 .remove = xo1_pm_remove, 180 }; 181 182 static int __init xo1_pm_init(void) 183 { 184 int r; 185 186 r = platform_driver_register(&cs5535_pms_driver); 187 if (r) 188 return r; 189 190 r = platform_driver_register(&cs5535_acpi_driver); 191 if (r) 192 platform_driver_unregister(&cs5535_pms_driver); 193 194 return r; 195 } 196 arch_initcall(xo1_pm_init); 197