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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220// SPDX-License-Identifier: GPL-2.0-only/* * kernel/power/suspend_test.c - Suspend to RAM and standby test facility. * * Copyright (c) 2009 Pavel Machek <pavel@ucw.cz> */
#include <linux/init.h>#include <linux/rtc.h>
#include "power.h"
/* * We test the system suspend code by setting an RTC wakealarm a short * time in the future, then suspending. Suspending the devices won't * normally take long ... some systems only need a few milliseconds. * * The time it takes is system-specific though, so when we test this * during system bootup we allow a LOT of time. */#define TEST_SUSPEND_SECONDS 10
static unsigned long suspend_test_start_time;static u32 test_repeat_count_max = 1;static u32 test_repeat_count_current;
void suspend_test_start(void){ /* FIXME Use better timebase than "jiffies", ideally a clocksource. * What we want is a hardware counter that will work correctly even * during the irqs-are-off stages of the suspend/resume cycle... */ suspend_test_start_time = jiffies;}
void suspend_test_finish(const char *label){ long nj = jiffies - suspend_test_start_time; unsigned msec;
msec = jiffies_to_msecs(abs(nj)); pr_info("PM: %s took %d.%03d seconds\n", label, msec / 1000, msec % 1000);
/* Warning on suspend means the RTC alarm period needs to be * larger -- the system was sooo slooowwww to suspend that the * alarm (should have) fired before the system went to sleep! * * Warning on either suspend or resume also means the system * has some performance issues. The stack dump of a WARN_ON * is more likely to get the right attention than a printk... */ WARN(msec > (TEST_SUSPEND_SECONDS * 1000), "Component: %s, time: %u\n", label, msec);}
/* * To test system suspend, we need a hands-off mechanism to resume the * system. RTCs wake alarms are a common self-contained mechanism. */
static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state){ static char err_readtime[] __initdata = KERN_ERR "PM: can't read %s time, err %d\n"; static char err_wakealarm [] __initdata = KERN_ERR "PM: can't set %s wakealarm, err %d\n"; static char err_suspend[] __initdata = KERN_ERR "PM: suspend test failed, error %d\n"; static char info_test[] __initdata = KERN_INFO "PM: test RTC wakeup from '%s' suspend\n";
time64_t now; struct rtc_wkalrm alm; int status;
/* this may fail if the RTC hasn't been initialized */repeat: status = rtc_read_time(rtc, &alm.time); if (status < 0) { printk(err_readtime, dev_name(&rtc->dev), status); return; } now = rtc_tm_to_time64(&alm.time);
memset(&alm, 0, sizeof alm); rtc_time64_to_tm(now + TEST_SUSPEND_SECONDS, &alm.time); alm.enabled = true;
status = rtc_set_alarm(rtc, &alm); if (status < 0) { printk(err_wakealarm, dev_name(&rtc->dev), status); return; }
if (state == PM_SUSPEND_MEM) { printk(info_test, pm_states[state]); status = pm_suspend(state); if (status == -ENODEV) state = PM_SUSPEND_STANDBY; } if (state == PM_SUSPEND_STANDBY) { printk(info_test, pm_states[state]); status = pm_suspend(state); if (status < 0) state = PM_SUSPEND_TO_IDLE; } if (state == PM_SUSPEND_TO_IDLE) { printk(info_test, pm_states[state]); status = pm_suspend(state); }
if (status < 0) printk(err_suspend, status);
test_repeat_count_current++; if (test_repeat_count_current < test_repeat_count_max) goto repeat;
/* Some platforms can't detect that the alarm triggered the * wakeup, or (accordingly) disable it after it afterwards. * It's supposed to give oneshot behavior; cope. */ alm.enabled = false; rtc_set_alarm(rtc, &alm);}
static int __init has_wakealarm(struct device *dev, const void *data){ struct rtc_device *candidate = to_rtc_device(dev);
if (!test_bit(RTC_FEATURE_ALARM, candidate->features)) return 0; if (!device_may_wakeup(candidate->dev.parent)) return 0;
return 1;}
/* * Kernel options like "test_suspend=mem" force suspend/resume sanity tests * at startup time. They're normally disabled, for faster boot and because * we can't know which states really work on this particular system. */static const char *test_state_label __initdata;
static char warn_bad_state[] __initdata = KERN_WARNING "PM: can't test '%s' suspend state\n";
static int __init setup_test_suspend(char *value){ int i; char *repeat; char *suspend_type;
/* example : "=mem[,N]" ==> "mem[,N]" */ value++; suspend_type = strsep(&value, ","); if (!suspend_type) return 1;
repeat = strsep(&value, ","); if (repeat) { if (kstrtou32(repeat, 0, &test_repeat_count_max)) return 1; }
for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) if (!strcmp(pm_labels[i], suspend_type)) { test_state_label = pm_labels[i]; return 1; }
printk(warn_bad_state, suspend_type); return 1;}__setup("test_suspend", setup_test_suspend);
static int __init test_suspend(void){ static char warn_no_rtc[] __initdata = KERN_WARNING "PM: no wakealarm-capable RTC driver is ready\n";
struct rtc_device *rtc = NULL; struct device *dev; suspend_state_t test_state;
/* PM is initialized by now; is that state testable? */ if (!test_state_label) return 0;
for (test_state = PM_SUSPEND_MIN; test_state < PM_SUSPEND_MAX; test_state++) { const char *state_label = pm_states[test_state];
if (state_label && !strcmp(test_state_label, state_label)) break; } if (test_state == PM_SUSPEND_MAX) { printk(warn_bad_state, test_state_label); return 0; }
/* RTCs have initialized by now too ... can we use one? */ dev = class_find_device(&rtc_class, NULL, NULL, has_wakealarm); if (dev) { rtc = rtc_class_open(dev_name(dev)); put_device(dev); } if (!rtc) { printk(warn_no_rtc); return 0; }
/* go for it */ test_wakealarm(rtc, test_state); rtc_class_close(rtc); return 0;}late_initcall(test_suspend);