linux-dev - Linux kernel development work

Age	Commit message (Collapse)	Author	Files	Lines
2016-11-29	timekeeping: Ignore the bogus sleep time if pm_trace is enabled	Chen Yu	1	-0/+1
	Power management suspend/resume tracing (ab)uses the RTC to store suspend/resume information persistently. As a consequence the RTC value is clobbered when timekeeping is resumed and tries to inject the sleep time. Commit a4f8f6667f09 ("timekeeping: Cap array access in timekeeping_debug") plugged a out of bounds array access in the timekeeping debug code which was caused by the clobbered RTC value, but we still use the clobbered RTC value for sleep time injection into kernel timekeeping, which will result in random adjustments depending on the stored "hash" value. To prevent this keep track of the RTC clobbering and ignore the invalid RTC timestamp at resume. If the system resumed successfully clear the flag, which marks the RTC as unusable, warn the user about the RTC clobber and recommend to adjust the RTC with 'ntpdate' or 'rdate'. [jstultz: Fixed up pr_warn formating, and implemented suggestions from Ingo] [ tglx: Rewrote changelog ] Originally-from: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Xunlei Pang <xlpang@redhat.com> Cc: Len Brown <lenb@kernel.org> Link: http://lkml.kernel.org/r/1480372524-15181-3-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-06-26	rtc: move mc146818 helper functions out-of-line	Arnd Bergmann	1	-191/+2
	The mc146818_get_time/mc146818_set_time functions are rather large inline functions in a global header file and are used in several drivers and in x86 specific code. Here we move them into a separate .c file that is compiled whenever any of the users require it. This also lets us remove the linux/acpi.h header inclusion from mc146818rtc.h, which in turn avoids some warnings about duplicate definition of the TRUE/FALSE macros. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-06-04	rtc: cmos: move mc146818rtc code out of asm-generic/rtc.h	Arnd Bergmann	1	-0/+194
	Drivers should not really include stuff from asm-generic directly, and the PC-style cmos rtc driver does this in order to reuse the mc146818 implementation of get_rtc_time/set_rtc_time rather than the architecture specific one for the architecture it gets built for. To make it more obvious what is going on, this moves and renames the two functions into include/linux/mc146818rtc.h, which holds the other mc146818 specific code. Ideally it would be in a .c file, but that would require extra infrastructure as the functions are called by multiple drivers with conflicting dependencies. With this change, the asm-generic/rtc.h header also becomes much more generic, so it can be reused more easily across any architecture that still relies on the genrtc driver. The only caller of the internal __get_rtc_time/__set_rtc_time functions is in arch/alpha/kernel/rtc.c, and we just change those over to the new naming. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2014-06-06	drivers/rtc/rtc-cmos.c: drivers/char/rtc.c features for DECstation support	Maciej W. Rozycki	1	-0/+4
	This brings in drivers/char/rtc.c functionality required for DECstation and, should the maintainers decide to switch, Alpha systems to use rtc-cmos. Specifically these features are made available: * RTC iomem rather than x86/PCI port I/O mapping, controlled with the RTC_IOMAPPED macro as with the original driver. The DS1287A chip in all DECstation systems is mapped in the host bus address space as a contiguous block of 64 32-bit words of which the least significant byte accesses the RTC chip for both reads and writes. All the address and data window register accesses are made transparently by the chipset glue logic so that the device appears directly mapped on the host bus. * A way to set the size of the address space explicitly with the newly-added `address_space' member of the platform part of the RTC device structure. This avoids the unreliable heuristics that does not work in a setup where the RTC is not explicitly accessed with the usual address and data window register pair. * The ability to use the RTC periodic interrupt as a system clock device, which is implemented by arch/mips/kernel/cevt-ds1287.c for DECstation systems and takes the RTC interrupt away from the RTC driver. Eventually hooking back to the clock device's interrupt handler should be possible for the purpose of the alarm clock and possibly also update-in-progress interrupt, but this is not done by this change. o To avoid interfering with the clock interrupt all the places where the RTC interrupt mask is fiddled with are only executed if and IRQ has been assigned to the RTC driver. o To avoid changing the clock setup Register A is not fiddled with if CMOS_RTC_FLAGS_NOFREQ is set in the newly-added `flags' member of the platform part of the RTC device structure. Originally, in drivers/char/rtc.c, this was keyed with the absence of the RTC interrupt, just like the interrupt mask, but there only the periodic interrupt frequency is set, whereas rtc-cmos also sets the divider bits. Therefore a new flag is introduced so that systems where the RTC interrupt is not usable rather than used as a system clock device can fully initialise the RTC. * A small clean-up is made to the IRQ assignment code that makes the IRQ number hardcoded to -1 rather than arbitrary -ENXIO (or whatever error happens to be returned by platform_get_irq) where no IRQ has been assigned to the RTC driver (NO_IRQ might be another candidate, but it looks like this macro has inconsistent or missing definitions and limited use and might therefore be unsafe). Verified to work correctly with a DECstation 5000/240 system. [akpm@linux-foundation.org: fix weird code layout] Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-14	rtc: fall back to requesting only the ports we actually use	Bjorn Helgaas	1	-0/+3
	Firmware like PNPBIOS or ACPI can report the address space consumed by the RTC. The actual space consumed may be less than the size (RTC_IO_EXTENT) assumed by the RTC driver. The PNP core doesn't request resources yet, but I'd like to make it do so. If/when it does, the RTC_IO_EXTENT request may fail, which prevents the RTC driver from loading. Since we only use the RTC index and data registers at RTC_PORT(0) and RTC_PORT(1), we can fall back to requesting just enough space for those. If the PNP core requests resources, this results in typical I/O port usage like this: 0070-0073 : 00:06 <-- PNP device 00:06 responds to 70-73 0070-0071 : rtc <-- RTC driver uses only 70-71 instead of the current: 0070-0077 : rtc <-- RTC_IO_EXTENT == 8 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: David Brownell <david-b@pacbell.net> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08	rtc-cmos wakeup interface	David Brownell	1	-0/+7
	I finally got around to testing the updated wakeup event hooks for rtc-cmos, and they follow in two patches: - Interface update ... when a simple enable_irq_wake() doesn't suffice, the platform data can hold suspend/resume callback hooks. - ACPI implementation ... provides callback hooks to do ACPI magic, and eliminate the legacy /proc/acpi/alarm file. The interface update could go into 2.6.21, but that's not essential; they will be NOPs on most PCs, without the ACPI stuff. I suspect the ACPI folk may have opinions about how to merge that second patch, and how to obsolete that legacy procfs file. I'd like to see that merge into 2.6.22 if possible... As for how to kick it in ... two ways: - The appended "rtcwake" program; updated since the last time it was posted, it deals much better with timezones and DST. - Write the /sys/class/rtc/.../wakealarm file, then go to sleep. For some reason RTC wake from "swsusp" stopped working on a system where it previously worked; the alarm setting appears to get clobbered. But on the bright side, RTC wake from "standby" worked on a system that had never been able to resume from that state before ... IDEACPI is my guess as to why it finally started to work. It's the old "two steps forward, one step back" dance, I guess. - Dave /* gcc -Wall -Os -o rtcwake rtcwake.c / #include <stdio.h> #include <getopt.h> #include <fcntl.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <errno.h> #include <time.h> #include <sys/ioctl.h> #include <sys/time.h> #include <sys/types.h> #include <linux/rtc.h> / constants from legacy PC/AT hardware / #define RTC_PF 0x40 #define RTC_AF 0x20 #define RTC_UF 0x10 / * rtcwake -- enter a system sleep state until specified wakeup time. * * This uses cross-platform Linux interfaces to enter a system sleep state, * and leave it no later than a specified time. It uses any RTC framework * driver that supports standard driver model wakeup flags. * * This is normally used like the old "apmsleep" utility, to wake from a * suspend state like ACPI S1 (standby) or S3 (suspend-to-RAM). Most * platforms can implement those without analogues of BIOS, APM, or ACPI. * * On some systems, this can also be used like "nvram-wakeup", waking * from states like ACPI S4 (suspend to disk). Not all systems have * persistent media that are appropriate for such suspend modes. * * The best way to set the system's RTC is so that it holds the current * time in UTC. Use the "-l" flag to tell this program that the system * RTC uses a local timezone instead (maybe you dual-boot MS-Windows). / static char progname; #ifdef DEBUG #define VERSION "1.0 dev (" __DATE__ " " __TIME__ ")" #else #define VERSION "0.9" #endif static unsigned verbose; static int rtc_is_utc = -1; static int may_wakeup(const char devname) { char buf[128], s; FILE f; snprintf(buf, sizeof buf, "/sys/class/rtc/%s/device/power/wakeup", devname); f = fopen(buf, "r"); if (!f) { perror(buf); return 0; } fgets(buf, sizeof buf, f); fclose(f); s = strchr(buf, '\n'); if (!s) return 0; s = 0; /* wakeup events could be disabled or not supported / return strcmp(buf, "enabled") == 0; } / all times should be in UTC / static time_t sys_time; static time_t rtc_time; static int get_basetimes(int fd) { struct tm tm; struct rtc_time rtc; / this process works in RTC time, except when working * with the system clock (which always uses UTC). / if (rtc_is_utc) setenv("TZ", "UTC", 1); tzset(); / read rtc and system clocks "at the same time", or as * precisely (+/- a second) as we can read them. / if (ioctl(fd, RTC_RD_TIME, &rtc) < 0) { perror("read rtc time"); return 0; } sys_time = time(0); if (sys_time == (time_t)-1) { perror("read system time"); return 0; } / convert rtc_time to normal arithmetic-friendly form, * updating tm.tm_wday as used by asctime(). / memset(&tm, 0, sizeof tm); tm.tm_sec = rtc.tm_sec; tm.tm_min = rtc.tm_min; tm.tm_hour = rtc.tm_hour; tm.tm_mday = rtc.tm_mday; tm.tm_mon = rtc.tm_mon; tm.tm_year = rtc.tm_year; tm.tm_isdst = rtc.tm_isdst; / stays unspecified? / rtc_time = mktime(&tm); if (rtc_time == (time_t)-1) { perror("convert rtc time"); return 0; } if (verbose) { if (!rtc_is_utc) { printf("\ttzone = %ld\n", timezone); printf("\ttzname = %s\n", tzname[daylight]); gmtime_r(&rtc_time, &tm); } printf("\tsystime = %ld, (UTC) %s", (long) sys_time, asctime(gmtime(&sys_time))); printf("\trtctime = %ld, (UTC) %s", (long) rtc_time, asctime(&tm)); } return 1; } static int setup_alarm(int fd, time_t wakeup) { struct tm tm; struct rtc_wkalrm wake; tm = gmtime(wakeup); wake.time.tm_sec = tm->tm_sec; wake.time.tm_min = tm->tm_min; wake.time.tm_hour = tm->tm_hour; wake.time.tm_mday = tm->tm_mday; wake.time.tm_mon = tm->tm_mon; wake.time.tm_year = tm->tm_year; wake.time.tm_wday = tm->tm_wday; wake.time.tm_yday = tm->tm_yday; wake.time.tm_isdst = tm->tm_isdst; / many rtc alarms only support up to 24 hours from 'now' ... / if ((rtc_time + (24 60 * 60)) > wakeup) { if (ioctl(fd, RTC_ALM_SET, &wake.time) < 0) { perror("set rtc alarm"); return 0; } if (ioctl(fd, RTC_AIE_ON, 0) < 0) { perror("enable rtc alarm"); return 0; } / ... so use the "more than 24 hours" request only if we must / } else { / avoid an extra AIE_ON call / wake.enabled = 1; if (ioctl(fd, RTC_WKALM_SET, &wake) < 0) { perror("set rtc wake alarm"); return 0; } } return 1; } static void suspend_system(const char suspend) { FILE f = fopen("/sys/power/state", "w"); if (!f) { perror("/sys/power/state"); return; } fprintf(f, "%s\n", suspend); fflush(f); / this executes after wake from suspend / fclose(f); } int main(int argc, char argv) { static char devname = "rtc0"; static unsigned seconds = 0; static char suspend = "standby"; int t; int fd; time_t alarm = 0; progname = strrchr(argv[0], '/'); if (progname) progname++; else progname = argv[0]; if (chdir("/dev/") < 0) { perror("chdir /dev"); return 1; } while ((t = getopt(argc, argv, "d:lm:s:t:uVv")) != EOF) { switch (t) { case 'd': devname = optarg; break; case 'l': rtc_is_utc = 0; break; / what system power mode to use? for now handle only * standardized mode names; eventually when systems define * their own state names, parse /sys/power/state. * * "on" is used just to test the RTC alarm mechanism, * bypassing all the wakeup-from-sleep infrastructure. / case 'm': if (strcmp(optarg, "standby") == 0 \|\| strcmp(optarg, "mem") == 0 \|\| strcmp(optarg, "disk") == 0 \|\| strcmp(optarg, "on") == 0 ) { suspend = optarg; break; } printf("%s: unrecognized suspend state '%s'\n", progname, optarg); goto usage; / alarm time, seconds-to-sleep (relative) / case 's': t = atoi(optarg); if (t < 0) { printf("%s: illegal interval %s seconds\n", progname, optarg); goto usage; } seconds = t; break; / alarm time, time_t (absolute, seconds since 1/1 1970 UTC) / case 't': t = atoi(optarg); if (t < 0) { printf("%s: illegal time_t value %s\n", progname, optarg); goto usage; } alarm = t; break; case 'u': rtc_is_utc = 1; break; case 'v': verbose++; break; case 'V': printf("%s: version %s\n", progname, VERSION); break; default: usage: printf("usage: %s [options]" "\n\t" "-d rtc0\|rtc1\|...\t(select rtc)" "\n\t" "-l\t\t\t(RTC uses local timezone)" "\n\t" "-m standby\|mem\|...\t(sleep mode)" "\n\t" "-s seconds\t\t(seconds to sleep)" "\n\t" "-t time_t\t\t(time to wake)" "\n\t" "-u\t\t\t(RTC uses UTC)" "\n\t" "-v\t\t\t(verbose messages)" "\n\t" "-V\t\t\t(show version)" "\n", progname); return 1; } } if (!alarm && !seconds) { printf("%s: must provide wake time\n", progname); goto usage; } / REVISIT: if /etc/adjtime exists, read it to see what * the util-linux version of hwclock assumes. / if (rtc_is_utc == -1) { printf("%s: assuming RTC uses UTC ...\n", progname); rtc_is_utc = 1; } / this RTC must exist and (if we'll sleep) be wakeup-enabled / fd = open(devname, O_RDONLY); if (fd < 0) { perror(devname); return 1; } if (strcmp(suspend, "on") != 0 && !may_wakeup(devname)) { printf("%s: %s not enabled for wakeup events\n", progname, devname); return 1; } / relative or absolute alarm time, normalized to time_t / if (!get_basetimes(fd)) return 1; if (verbose) printf("alarm %ld, sys_time %ld, rtc_time %ld, seconds %u\n", alarm, sys_time, rtc_time, seconds); if (alarm) { if (alarm < sys_time) { printf("%s: time doesn't go backward to %s", progname, ctime(&alarm)); return 1; } alarm += sys_time - rtc_time; } else alarm = rtc_time + seconds + 1; if (setup_alarm(fd, &alarm) < 0) return 1; sync(); printf("%s: wakeup from \"%s\" using %s at %s", progname, suspend, devname, ctime(&alarm)); fflush(stdout); usleep(10 1000); if (strcmp(suspend, "on") != 0) suspend_system(suspend); else { unsigned long data; do { t = read(fd, &data, sizeof data); if (t < 0) { perror("rtc read"); break; } if (verbose) printf("... %s: %03lx\n", devname, data); } while (!(data & RTC_AF)); } if (ioctl(fd, RTC_AIE_OFF, 0) < 0) perror("disable rtc alarm interrupt"); close(fd); return 0; } This patch: Make rtc-cmos do the relevant magic so this RTC can wake the system from a sleep state. That magic comes in two basic flavors: - Straightforward: enable_irq_wake(), the way it'd work on most SOC chips; or generally with system sleep states which don't disable core IRQ logic. - Roundabout, using non-IRQ platform hooks. This is needed with ACPI and one almost-clone chip which uses a special wakeup-only alarm. (That's the RTC used on Footbridge boards, FWIW, which don't do PM in Linux.) A separate patch implements those hooks for ACPI platforms, so that rtc_cmos can issue system wakeup events (and its sysfs "wakealarm" attribute works on at least some systems). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11	[PATCH] RTC framework driver for CMOS RTCs	David Brownell	1	-0/+10
	This is an "RTC framework" driver for the "CMOS" RTCs which are standard on PCs and some other platforms. That's MC146818 compatible silicon. Advantages of this vs. drivers/char/rtc.c (use one _or_ the other, only one will be able to claim the RTC irq) include: - This leverages both the new RTC framework and the driver model; both PNPACPI and platform device modes are supported. (A separate patch creates a platform device on PCs where PNPACPI isn't configured.) - It supports common extensions like longer alarms. (A separate patch exports that information from ACPI through platform_data.) - Likewise, system wakeup events use "real driver model support", with policy control via sysfs "wakeup" attributes and and using normal rtc ioctls to manage wakeup. (Patch in the works. The ACPI hooks are known; /proc/acpi/alarm can vanish. Making it work with EFI will be a minor challenge to someone with e.g. a MiniMac.) It's not yet been tested on non-x86 systems, without ACPI, or with HPET. And the RTC framework will surely have teething pains on "mainstream" PC-based systems (though must embedded Linux systems use it heavily), not limited to sorting out the "/dev/rtc0" issue (udev easily tweaked). Also, the ALSA rtctimer code doesn't use the new RTC API. Otherwise, this should be a no-known-regressions replacement for the old drivers/char/rtc.c driver, and should help the non-embedded distros (and the new timekeeping code) start to switch to the framework. Note also that any systems using "rtc-m48t86" are candidates to switch over to this more functional driver; the platform data is different, and the way bytes are read is different, but otherwise those chips should be compatible. [akpm@osdl.org: sparc32 fix] [akpm@osdl.org: sparc64 fix] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Woody Suwalski <woodys@xandros.com> Cc: Alessandro Zummo <alessandro.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-07-10	[PATCH] char/rtc: Handle memory-mapped chips properly	Maciej W. Rozycki	1	-0/+7
	Handle memory-mapped chips properly, needed for example on DECstations. This support was in Linux 2.4 but for some reason got lost in 2.6. This patch is taken directly from the linux-mips repository. [akpm@osdl.org: cleanup] Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Martin Michlmayr <tbm@cyrius.com> Cc: Paul Gortmaker <penguin@muskoka.com> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16	Linux-2.6.12-rc2	Linus Torvalds	1	-0/+92
	Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!