1a9d70523SRafael J. Wysocki /* 2a9d70523SRafael J. Wysocki * kernel/power/suspend_test.c - Suspend to RAM and standby test facility. 3a9d70523SRafael J. Wysocki * 4a9d70523SRafael J. Wysocki * Copyright (c) 2009 Pavel Machek <pavel@ucw.cz> 5a9d70523SRafael J. Wysocki * 6a9d70523SRafael J. Wysocki * This file is released under the GPLv2. 7a9d70523SRafael J. Wysocki */ 8a9d70523SRafael J. Wysocki 9a9d70523SRafael J. Wysocki #include <linux/init.h> 10a9d70523SRafael J. Wysocki #include <linux/rtc.h> 11a9d70523SRafael J. Wysocki 12a9d70523SRafael J. Wysocki #include "power.h" 13a9d70523SRafael J. Wysocki 14a9d70523SRafael J. Wysocki /* 15a9d70523SRafael J. Wysocki * We test the system suspend code by setting an RTC wakealarm a short 16a9d70523SRafael J. Wysocki * time in the future, then suspending. Suspending the devices won't 17a9d70523SRafael J. Wysocki * normally take long ... some systems only need a few milliseconds. 18a9d70523SRafael J. Wysocki * 19a9d70523SRafael J. Wysocki * The time it takes is system-specific though, so when we test this 20a9d70523SRafael J. Wysocki * during system bootup we allow a LOT of time. 21a9d70523SRafael J. Wysocki */ 2204bf7539SRafael J. Wysocki #define TEST_SUSPEND_SECONDS 10 23a9d70523SRafael J. Wysocki 24a9d70523SRafael J. Wysocki static unsigned long suspend_test_start_time; 252ce98689SSrinivas Pandruvada static u32 test_repeat_count_max = 1; 262ce98689SSrinivas Pandruvada static u32 test_repeat_count_current; 27a9d70523SRafael J. Wysocki 28a9d70523SRafael J. Wysocki void suspend_test_start(void) 29a9d70523SRafael J. Wysocki { 30a9d70523SRafael J. Wysocki /* FIXME Use better timebase than "jiffies", ideally a clocksource. 31a9d70523SRafael J. Wysocki * What we want is a hardware counter that will work correctly even 32a9d70523SRafael J. Wysocki * during the irqs-are-off stages of the suspend/resume cycle... 33a9d70523SRafael J. Wysocki */ 34a9d70523SRafael J. Wysocki suspend_test_start_time = jiffies; 35a9d70523SRafael J. Wysocki } 36a9d70523SRafael J. Wysocki 37a9d70523SRafael J. Wysocki void suspend_test_finish(const char *label) 38a9d70523SRafael J. Wysocki { 39a9d70523SRafael J. Wysocki long nj = jiffies - suspend_test_start_time; 40a9d70523SRafael J. Wysocki unsigned msec; 41a9d70523SRafael J. Wysocki 42a9d70523SRafael J. Wysocki msec = jiffies_to_msecs(abs(nj)); 43a9d70523SRafael J. Wysocki pr_info("PM: %s took %d.%03d seconds\n", label, 44a9d70523SRafael J. Wysocki msec / 1000, msec % 1000); 45a9d70523SRafael J. Wysocki 46a9d70523SRafael J. Wysocki /* Warning on suspend means the RTC alarm period needs to be 47a9d70523SRafael J. Wysocki * larger -- the system was sooo slooowwww to suspend that the 48a9d70523SRafael J. Wysocki * alarm (should have) fired before the system went to sleep! 49a9d70523SRafael J. Wysocki * 50a9d70523SRafael J. Wysocki * Warning on either suspend or resume also means the system 51a9d70523SRafael J. Wysocki * has some performance issues. The stack dump of a WARN_ON 52a9d70523SRafael J. Wysocki * is more likely to get the right attention than a printk... 53a9d70523SRafael J. Wysocki */ 5404bf7539SRafael J. Wysocki WARN(msec > (TEST_SUSPEND_SECONDS * 1000), 5504bf7539SRafael J. Wysocki "Component: %s, time: %u\n", label, msec); 56a9d70523SRafael J. Wysocki } 57a9d70523SRafael J. Wysocki 58a9d70523SRafael J. Wysocki /* 59a9d70523SRafael J. Wysocki * To test system suspend, we need a hands-off mechanism to resume the 60a9d70523SRafael J. Wysocki * system. RTCs wake alarms are a common self-contained mechanism. 61a9d70523SRafael J. Wysocki */ 62a9d70523SRafael J. Wysocki 63a9d70523SRafael J. Wysocki static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state) 64a9d70523SRafael J. Wysocki { 65a9d70523SRafael J. Wysocki static char err_readtime[] __initdata = 66a9d70523SRafael J. Wysocki KERN_ERR "PM: can't read %s time, err %d\n"; 67a9d70523SRafael J. Wysocki static char err_wakealarm [] __initdata = 68a9d70523SRafael J. Wysocki KERN_ERR "PM: can't set %s wakealarm, err %d\n"; 69a9d70523SRafael J. Wysocki static char err_suspend[] __initdata = 70a9d70523SRafael J. Wysocki KERN_ERR "PM: suspend test failed, error %d\n"; 71a9d70523SRafael J. Wysocki static char info_test[] __initdata = 72a9d70523SRafael J. Wysocki KERN_INFO "PM: test RTC wakeup from '%s' suspend\n"; 73a9d70523SRafael J. Wysocki 74a9d70523SRafael J. Wysocki unsigned long now; 75a9d70523SRafael J. Wysocki struct rtc_wkalrm alm; 76a9d70523SRafael J. Wysocki int status; 77a9d70523SRafael J. Wysocki 78a9d70523SRafael J. Wysocki /* this may fail if the RTC hasn't been initialized */ 792ce98689SSrinivas Pandruvada repeat: 80a9d70523SRafael J. Wysocki status = rtc_read_time(rtc, &alm.time); 81a9d70523SRafael J. Wysocki if (status < 0) { 82a9d70523SRafael J. Wysocki printk(err_readtime, dev_name(&rtc->dev), status); 83a9d70523SRafael J. Wysocki return; 84a9d70523SRafael J. Wysocki } 85a9d70523SRafael J. Wysocki rtc_tm_to_time(&alm.time, &now); 86a9d70523SRafael J. Wysocki 87a9d70523SRafael J. Wysocki memset(&alm, 0, sizeof alm); 88a9d70523SRafael J. Wysocki rtc_time_to_tm(now + TEST_SUSPEND_SECONDS, &alm.time); 89a9d70523SRafael J. Wysocki alm.enabled = true; 90a9d70523SRafael J. Wysocki 91a9d70523SRafael J. Wysocki status = rtc_set_alarm(rtc, &alm); 92a9d70523SRafael J. Wysocki if (status < 0) { 93a9d70523SRafael J. Wysocki printk(err_wakealarm, dev_name(&rtc->dev), status); 94a9d70523SRafael J. Wysocki return; 95a9d70523SRafael J. Wysocki } 96a9d70523SRafael J. Wysocki 97a9d70523SRafael J. Wysocki if (state == PM_SUSPEND_MEM) { 98d431cbc5SRafael J. Wysocki printk(info_test, pm_states[state]); 99a9d70523SRafael J. Wysocki status = pm_suspend(state); 100a9d70523SRafael J. Wysocki if (status == -ENODEV) 101a9d70523SRafael J. Wysocki state = PM_SUSPEND_STANDBY; 102a9d70523SRafael J. Wysocki } 103a9d70523SRafael J. Wysocki if (state == PM_SUSPEND_STANDBY) { 104d431cbc5SRafael J. Wysocki printk(info_test, pm_states[state]); 105a9d70523SRafael J. Wysocki status = pm_suspend(state); 106bc7115b1SSrinivas Pandruvada if (status < 0) 107bc7115b1SSrinivas Pandruvada state = PM_SUSPEND_FREEZE; 108a9d70523SRafael J. Wysocki } 109bc7115b1SSrinivas Pandruvada if (state == PM_SUSPEND_FREEZE) { 110bc7115b1SSrinivas Pandruvada printk(info_test, pm_states[state]); 111bc7115b1SSrinivas Pandruvada status = pm_suspend(state); 112bc7115b1SSrinivas Pandruvada } 113bc7115b1SSrinivas Pandruvada 114a9d70523SRafael J. Wysocki if (status < 0) 115a9d70523SRafael J. Wysocki printk(err_suspend, status); 116a9d70523SRafael J. Wysocki 1172ce98689SSrinivas Pandruvada test_repeat_count_current++; 1182ce98689SSrinivas Pandruvada if (test_repeat_count_current < test_repeat_count_max) 1192ce98689SSrinivas Pandruvada goto repeat; 1202ce98689SSrinivas Pandruvada 121a9d70523SRafael J. Wysocki /* Some platforms can't detect that the alarm triggered the 122a9d70523SRafael J. Wysocki * wakeup, or (accordingly) disable it after it afterwards. 123a9d70523SRafael J. Wysocki * It's supposed to give oneshot behavior; cope. 124a9d70523SRafael J. Wysocki */ 125a9d70523SRafael J. Wysocki alm.enabled = false; 126a9d70523SRafael J. Wysocki rtc_set_alarm(rtc, &alm); 127a9d70523SRafael J. Wysocki } 128a9d70523SRafael J. Wysocki 1299f3b795aSMichał Mirosław static int __init has_wakealarm(struct device *dev, const void *data) 130a9d70523SRafael J. Wysocki { 131a9d70523SRafael J. Wysocki struct rtc_device *candidate = to_rtc_device(dev); 132a9d70523SRafael J. Wysocki 133a9d70523SRafael J. Wysocki if (!candidate->ops->set_alarm) 134a9d70523SRafael J. Wysocki return 0; 135a9d70523SRafael J. Wysocki if (!device_may_wakeup(candidate->dev.parent)) 136a9d70523SRafael J. Wysocki return 0; 137a9d70523SRafael J. Wysocki 138a9d70523SRafael J. Wysocki return 1; 139a9d70523SRafael J. Wysocki } 140a9d70523SRafael J. Wysocki 141a9d70523SRafael J. Wysocki /* 142a9d70523SRafael J. Wysocki * Kernel options like "test_suspend=mem" force suspend/resume sanity tests 143a9d70523SRafael J. Wysocki * at startup time. They're normally disabled, for faster boot and because 144a9d70523SRafael J. Wysocki * we can't know which states really work on this particular system. 145a9d70523SRafael J. Wysocki */ 14662109b43SRafael J. Wysocki static const char *test_state_label __initdata; 147a9d70523SRafael J. Wysocki 148a9d70523SRafael J. Wysocki static char warn_bad_state[] __initdata = 149a9d70523SRafael J. Wysocki KERN_WARNING "PM: can't test '%s' suspend state\n"; 150a9d70523SRafael J. Wysocki 151a9d70523SRafael J. Wysocki static int __init setup_test_suspend(char *value) 152a9d70523SRafael J. Wysocki { 15362109b43SRafael J. Wysocki int i; 1542ce98689SSrinivas Pandruvada char *repeat; 1552ce98689SSrinivas Pandruvada char *suspend_type; 156a9d70523SRafael J. Wysocki 1572ce98689SSrinivas Pandruvada /* example : "=mem[,N]" ==> "mem[,N]" */ 158a9d70523SRafael J. Wysocki value++; 1592ce98689SSrinivas Pandruvada suspend_type = strsep(&value, ","); 1602ce98689SSrinivas Pandruvada if (!suspend_type) 1612ce98689SSrinivas Pandruvada return 0; 1622ce98689SSrinivas Pandruvada 1632ce98689SSrinivas Pandruvada repeat = strsep(&value, ","); 1642ce98689SSrinivas Pandruvada if (repeat) { 1652ce98689SSrinivas Pandruvada if (kstrtou32(repeat, 0, &test_repeat_count_max)) 1662ce98689SSrinivas Pandruvada return 0; 1672ce98689SSrinivas Pandruvada } 1682ce98689SSrinivas Pandruvada 169*8cff6679SGeert Uytterhoeven for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) 1702ce98689SSrinivas Pandruvada if (!strcmp(pm_labels[i], suspend_type)) { 17162109b43SRafael J. Wysocki test_state_label = pm_labels[i]; 172a9d70523SRafael J. Wysocki return 0; 173a9d70523SRafael J. Wysocki } 17427ddcc65SRafael J. Wysocki 1752ce98689SSrinivas Pandruvada printk(warn_bad_state, suspend_type); 176a9d70523SRafael J. Wysocki return 0; 177a9d70523SRafael J. Wysocki } 178a9d70523SRafael J. Wysocki __setup("test_suspend", setup_test_suspend); 179a9d70523SRafael J. Wysocki 180a9d70523SRafael J. Wysocki static int __init test_suspend(void) 181a9d70523SRafael J. Wysocki { 182a9d70523SRafael J. Wysocki static char warn_no_rtc[] __initdata = 183a9d70523SRafael J. Wysocki KERN_WARNING "PM: no wakealarm-capable RTC driver is ready\n"; 184a9d70523SRafael J. Wysocki 185a9d70523SRafael J. Wysocki struct rtc_device *rtc = NULL; 1869f3b795aSMichał Mirosław struct device *dev; 18762109b43SRafael J. Wysocki suspend_state_t test_state; 188a9d70523SRafael J. Wysocki 189a9d70523SRafael J. Wysocki /* PM is initialized by now; is that state testable? */ 19062109b43SRafael J. Wysocki if (!test_state_label) 19162109b43SRafael J. Wysocki return 0; 19262109b43SRafael J. Wysocki 19362109b43SRafael J. Wysocki for (test_state = PM_SUSPEND_MIN; test_state < PM_SUSPEND_MAX; test_state++) { 19462109b43SRafael J. Wysocki const char *state_label = pm_states[test_state]; 19562109b43SRafael J. Wysocki 19662109b43SRafael J. Wysocki if (state_label && !strcmp(test_state_label, state_label)) 19762109b43SRafael J. Wysocki break; 19862109b43SRafael J. Wysocki } 19962109b43SRafael J. Wysocki if (test_state == PM_SUSPEND_MAX) { 20062109b43SRafael J. Wysocki printk(warn_bad_state, test_state_label); 20162109b43SRafael J. Wysocki return 0; 202a9d70523SRafael J. Wysocki } 203a9d70523SRafael J. Wysocki 204a9d70523SRafael J. Wysocki /* RTCs have initialized by now too ... can we use one? */ 2059f3b795aSMichał Mirosław dev = class_find_device(rtc_class, NULL, NULL, has_wakealarm); 206ceb75787SJohan Hovold if (dev) { 2079f3b795aSMichał Mirosław rtc = rtc_class_open(dev_name(dev)); 208ceb75787SJohan Hovold put_device(dev); 209ceb75787SJohan Hovold } 210a9d70523SRafael J. Wysocki if (!rtc) { 211a9d70523SRafael J. Wysocki printk(warn_no_rtc); 21262109b43SRafael J. Wysocki return 0; 213a9d70523SRafael J. Wysocki } 214a9d70523SRafael J. Wysocki 215a9d70523SRafael J. Wysocki /* go for it */ 216a9d70523SRafael J. Wysocki test_wakealarm(rtc, test_state); 217a9d70523SRafael J. Wysocki rtc_class_close(rtc); 218a9d70523SRafael J. Wysocki return 0; 219a9d70523SRafael J. Wysocki } 220a9d70523SRafael J. Wysocki late_initcall(test_suspend); 221