Maxime Ripard | ae499f0 | 2014-07-03 14:07:18 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Atmel AT91 SAM9 SoCs reset code |
| 3 | * |
| 4 | * Copyright (C) 2007 Atmel Corporation. |
| 5 | * Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> |
| 6 | * Copyright (C) 2014 Free Electrons |
| 7 | * |
| 8 | * This file is licensed under the terms of the GNU General Public |
| 9 | * License version 2. This program is licensed "as is" without any |
| 10 | * warranty of any kind, whether express or implied. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/io.h> |
| 14 | #include <linux/module.h> |
| 15 | #include <linux/of.h> |
| 16 | #include <linux/platform_device.h> |
| 17 | #include <linux/printk.h> |
| 18 | |
| 19 | #define AT91_SHDW_CR 0x00 /* Shut Down Control Register */ |
| 20 | #define AT91_SHDW_SHDW BIT(0) /* Shut Down command */ |
| 21 | #define AT91_SHDW_KEY (0xa5 << 24) /* KEY Password */ |
| 22 | |
| 23 | #define AT91_SHDW_MR 0x04 /* Shut Down Mode Register */ |
| 24 | #define AT91_SHDW_WKMODE0 GENMASK(2, 0) /* Wake-up 0 Mode Selection */ |
| 25 | #define AT91_SHDW_CPTWK0_MAX 0xf /* Maximum Counter On Wake Up 0 */ |
| 26 | #define AT91_SHDW_CPTWK0 (AT91_SHDW_CPTWK0_MAX << 4) /* Counter On Wake Up 0 */ |
| 27 | #define AT91_SHDW_CPTWK0_(x) ((x) << 4) |
| 28 | #define AT91_SHDW_RTTWKEN BIT(16) /* Real Time Timer Wake-up Enable */ |
| 29 | #define AT91_SHDW_RTCWKEN BIT(17) /* Real Time Clock Wake-up Enable */ |
| 30 | |
| 31 | #define AT91_SHDW_SR 0x08 /* Shut Down Status Register */ |
| 32 | #define AT91_SHDW_WAKEUP0 BIT(0) /* Wake-up 0 Status */ |
| 33 | #define AT91_SHDW_RTTWK BIT(16) /* Real-time Timer Wake-up */ |
| 34 | #define AT91_SHDW_RTCWK BIT(17) /* Real-time Clock Wake-up [SAM9RL] */ |
| 35 | |
| 36 | enum wakeup_type { |
| 37 | AT91_SHDW_WKMODE0_NONE = 0, |
| 38 | AT91_SHDW_WKMODE0_HIGH = 1, |
| 39 | AT91_SHDW_WKMODE0_LOW = 2, |
| 40 | AT91_SHDW_WKMODE0_ANYLEVEL = 3, |
| 41 | }; |
| 42 | |
| 43 | static const char *shdwc_wakeup_modes[] = { |
| 44 | [AT91_SHDW_WKMODE0_NONE] = "none", |
| 45 | [AT91_SHDW_WKMODE0_HIGH] = "high", |
| 46 | [AT91_SHDW_WKMODE0_LOW] = "low", |
| 47 | [AT91_SHDW_WKMODE0_ANYLEVEL] = "any", |
| 48 | }; |
| 49 | |
| 50 | static void __iomem *at91_shdwc_base; |
| 51 | |
| 52 | static void __init at91_wakeup_status(void) |
| 53 | { |
Nicolas Ferre | 405a72c | 2014-09-01 16:11:19 +0200 | [diff] [blame] | 54 | u32 reg = readl(at91_shdwc_base + AT91_SHDW_SR); |
Maxime Ripard | ae499f0 | 2014-07-03 14:07:18 +0200 | [diff] [blame] | 55 | char *reason = "unknown"; |
| 56 | |
| 57 | /* Simple power-on, just bail out */ |
| 58 | if (!reg) |
| 59 | return; |
| 60 | |
| 61 | if (reg & AT91_SHDW_RTTWK) |
| 62 | reason = "RTT"; |
| 63 | else if (reg & AT91_SHDW_RTCWK) |
| 64 | reason = "RTC"; |
| 65 | |
| 66 | pr_info("AT91: Wake-Up source: %s\n", reason); |
| 67 | } |
| 68 | |
| 69 | static void at91_poweroff(void) |
| 70 | { |
| 71 | writel(AT91_SHDW_KEY | AT91_SHDW_SHDW, at91_shdwc_base + AT91_SHDW_CR); |
| 72 | } |
| 73 | |
Guenter Roeck | a538cf0 | 2014-10-10 17:41:17 -0700 | [diff] [blame] | 74 | static int at91_poweroff_get_wakeup_mode(struct device_node *np) |
Maxime Ripard | ae499f0 | 2014-07-03 14:07:18 +0200 | [diff] [blame] | 75 | { |
| 76 | const char *pm; |
Guenter Roeck | a538cf0 | 2014-10-10 17:41:17 -0700 | [diff] [blame] | 77 | unsigned int i; |
| 78 | int err; |
Maxime Ripard | ae499f0 | 2014-07-03 14:07:18 +0200 | [diff] [blame] | 79 | |
| 80 | err = of_property_read_string(np, "atmel,wakeup-mode", &pm); |
| 81 | if (err < 0) |
| 82 | return AT91_SHDW_WKMODE0_ANYLEVEL; |
| 83 | |
| 84 | for (i = 0; i < ARRAY_SIZE(shdwc_wakeup_modes); i++) |
| 85 | if (!strcasecmp(pm, shdwc_wakeup_modes[i])) |
| 86 | return i; |
| 87 | |
| 88 | return -ENODEV; |
| 89 | } |
| 90 | |
| 91 | static void at91_poweroff_dt_set_wakeup_mode(struct platform_device *pdev) |
| 92 | { |
| 93 | struct device_node *np = pdev->dev.of_node; |
Guenter Roeck | a538cf0 | 2014-10-10 17:41:17 -0700 | [diff] [blame] | 94 | int wakeup_mode; |
Maxime Ripard | ae499f0 | 2014-07-03 14:07:18 +0200 | [diff] [blame] | 95 | u32 mode = 0, tmp; |
| 96 | |
| 97 | wakeup_mode = at91_poweroff_get_wakeup_mode(np); |
| 98 | if (wakeup_mode < 0) { |
| 99 | dev_warn(&pdev->dev, "shdwc unknown wakeup mode\n"); |
| 100 | return; |
| 101 | } |
| 102 | |
| 103 | if (!of_property_read_u32(np, "atmel,wakeup-counter", &tmp)) { |
| 104 | if (tmp > AT91_SHDW_CPTWK0_MAX) { |
| 105 | dev_warn(&pdev->dev, |
| 106 | "shdwc wakeup counter 0x%x > 0x%x reduce it to 0x%x\n", |
| 107 | tmp, AT91_SHDW_CPTWK0_MAX, AT91_SHDW_CPTWK0_MAX); |
| 108 | tmp = AT91_SHDW_CPTWK0_MAX; |
| 109 | } |
| 110 | mode |= AT91_SHDW_CPTWK0_(tmp); |
| 111 | } |
| 112 | |
| 113 | if (of_property_read_bool(np, "atmel,wakeup-rtc-timer")) |
| 114 | mode |= AT91_SHDW_RTCWKEN; |
| 115 | |
| 116 | if (of_property_read_bool(np, "atmel,wakeup-rtt-timer")) |
| 117 | mode |= AT91_SHDW_RTTWKEN; |
| 118 | |
| 119 | writel(wakeup_mode | mode, at91_shdwc_base + AT91_SHDW_MR); |
| 120 | } |
| 121 | |
| 122 | static int at91_poweroff_probe(struct platform_device *pdev) |
| 123 | { |
| 124 | struct resource *res; |
| 125 | |
| 126 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 127 | at91_shdwc_base = devm_ioremap_resource(&pdev->dev, res); |
| 128 | if (IS_ERR(at91_shdwc_base)) { |
| 129 | dev_err(&pdev->dev, "Could not map reset controller address\n"); |
| 130 | return PTR_ERR(at91_shdwc_base); |
| 131 | } |
| 132 | |
| 133 | at91_wakeup_status(); |
| 134 | |
| 135 | if (pdev->dev.of_node) |
| 136 | at91_poweroff_dt_set_wakeup_mode(pdev); |
| 137 | |
| 138 | pm_power_off = at91_poweroff; |
| 139 | |
| 140 | return 0; |
| 141 | } |
| 142 | |
Fabian Frederick | 8fb0885 | 2015-03-16 20:17:12 +0100 | [diff] [blame] | 143 | static const struct of_device_id at91_poweroff_of_match[] = { |
Maxime Ripard | ae499f0 | 2014-07-03 14:07:18 +0200 | [diff] [blame] | 144 | { .compatible = "atmel,at91sam9260-shdwc", }, |
| 145 | { .compatible = "atmel,at91sam9rl-shdwc", }, |
| 146 | { .compatible = "atmel,at91sam9x5-shdwc", }, |
| 147 | { /*sentinel*/ } |
| 148 | }; |
| 149 | |
| 150 | static struct platform_driver at91_poweroff_driver = { |
| 151 | .probe = at91_poweroff_probe, |
| 152 | .driver = { |
| 153 | .name = "at91-poweroff", |
| 154 | .of_match_table = at91_poweroff_of_match, |
| 155 | }, |
| 156 | }; |
| 157 | module_platform_driver(at91_poweroff_driver); |