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diff --git a/docs/docs.kernel.org_power_s2ram.txt b/docs/docs.kernel.org_power_s2ram.txt new file mode 100644 index 0000000..1113b00 --- /dev/null +++ b/docs/docs.kernel.org_power_s2ram.txt @@ -0,0 +1,202 @@ + #[1]Index [2]Search [3]Interaction of Suspend code (S3) with the CPU + hotplug infrastructure [4]Runtime Power Management Framework for I/O + Devices + +[5]The Linux Kernel + + 6.7.0 + +Quick search + + ____________________ Go + +Contents + + [X] + * [6]A guide to the Kernel Development Process + * [7]Submitting patches: the essential guide to getting your code + into the kernel + * [8]Code of conduct + * [9]Kernel Maintainer Handbook + * [10]All development-process docs + + * [11]Core API Documentation + * [12]Driver implementer's API guide + * [13]Kernel subsystem documentation + + [14]Core subsystems + o [15]Core API Documentation + o [16]Driver implementer's API guide + o [17]Memory Management Documentation + o [18]Power Management + o [19]Scheduler + o [20]Timers + o [21]Locking + + [22]Human interfaces + + [23]Networking interfaces + + [24]Storage interfaces + * [25]Locking in the kernel + + * [26]Linux kernel licensing rules + * [27]How to write kernel documentation + * [28]Development tools for the kernel + * [29]Kernel Testing Guide + * [30]Kernel Hacking Guides + * [31]Linux Tracing Technologies + * [32]fault-injection + * [33]Kernel Livepatching + * [34]Rust + + * [35]The Linux kernel user's and administrator's guide + * [36]The kernel build system + * [37]Reporting issues + * [38]User-space tools + * [39]The Linux kernel user-space API guide + + * [40]The Linux kernel firmware guide + * [41]Open Firmware and Devicetree + + * [42]CPU Architectures + + * [43]Unsorted Documentation + + * [44]Translations + +This Page + + * [45]Show Source + +How to get s2ram working[46]¶ + + 2006 Linus Torvalds 2006 Pavel Machek + 1. Check suspend.sf.net, program s2ram there has long whitelist of + "known ok" machines, along with tricks to use on each one. + 2. If that does not help, try reading [47]swsusp/S3 tricks and + [48]Video issues with S3 resume. Perhaps problem is as simple as + broken module, and simple module unload can fix it. + 3. You can use Linus' TRACE_RESUME infrastructure, described below. + +Using TRACE_RESUME[49]¶ + + I've been working at making the machines I have able to STR, and almost + always it's a driver that is buggy. Thank God for the suspend/resume + debugging - the thing that Chuck tried to disable. That's often the + _only_ way to debug these things, and it's actually pretty powerful + (but time-consuming - having to insert TRACE_RESUME() markers into the + device driver that doesn't resume and recompile and reboot). + + Anyway, the way to debug this for people who are interested (have a + machine that doesn't boot) is: + + * enable PM_DEBUG, and PM_TRACE + * use a script like this: +#!/bin/sh +sync +echo 1 > /sys/power/pm_trace +echo mem > /sys/power/state + + to suspend + * if it doesn't come back up (which is usually the problem), reboot + by holding the power button down, and look at the dmesg output for + things like: +Magic number: 4:156:725 +hash matches drivers/base/power/resume.c:28 +hash matches device 0000:01:00.0 + + which means that the last trace event was just before trying to + resume device 0000:01:00.0. Then figure out what driver is + controlling that device (lspci and /sys/devices/pci* is your + friend), and see if you can fix it, disable it, or trace into its + resume function. + If no device matches the hash (or any matches appear to be false + positives), the culprit may be a device from a loadable kernel + module that is not loaded until after the hash is checked. You can + check the hash against the current devices again after more modules + are loaded using sysfs: +cat /sys/power/pm_trace_dev_match + + For example, the above happens to be the VGA device on my EVO, which I + used to run with "radeonfb" (it's an ATI Radeon mobility). It turns out + that "radeonfb" simply cannot resume that device - it tries to set the + PLL's, and it just _hangs_. Using the regular VGA console and letting X + resume it instead works fine. + +NOTE[50]¶ + + pm_trace uses the system's Real Time Clock (RTC) to save the magic + number. Reason for this is that the RTC is the only reliably available + piece of hardware during resume operations where a value can be set + that will survive a reboot. + + pm_trace is not compatible with asynchronous suspend, so it turns + asynchronous suspend off (which may work around timing or + ordering-sensitive bugs). + + Consequence is that after a resume (even if it is successful) your + system clock will have a value corresponding to the magic number + instead of the correct date/time! It is therefore advisable to use a + program like ntp-date or rdate to reset the correct date/time from an + external time source when using this trace option. + + As the clock keeps ticking it is also essential that the reboot is done + quickly after the resume failure. The trace option does not use the + seconds or the low order bits of the minutes of the RTC, but a too long + delay will corrupt the magic value. + + ©The kernel development community. | Powered by [51]Sphinx 5.0.1 & + [52]Alabaster 0.7.12 | [53]Page source + +References + + 1. https://docs.kernel.org/genindex.html + 2. https://docs.kernel.org/search.html + 3. https://docs.kernel.org/power/suspend-and-cpuhotplug.html + 4. https://docs.kernel.org/power/runtime_pm.html + 5. https://docs.kernel.org/index.html + 6. https://docs.kernel.org/process/development-process.html + 7. https://docs.kernel.org/process/submitting-patches.html + 8. https://docs.kernel.org/process/code-of-conduct.html + 9. https://docs.kernel.org/maintainer/index.html + 10. https://docs.kernel.org/process/index.html + 11. https://docs.kernel.org/core-api/index.html + 12. https://docs.kernel.org/driver-api/index.html + 13. https://docs.kernel.org/subsystem-apis.html + 14. https://docs.kernel.org/subsystem-apis.html#core-subsystems + 15. https://docs.kernel.org/core-api/index.html + 16. https://docs.kernel.org/driver-api/index.html + 17. https://docs.kernel.org/mm/index.html + 18. https://docs.kernel.org/power/index.html + 19. https://docs.kernel.org/scheduler/index.html + 20. https://docs.kernel.org/timers/index.html + 21. https://docs.kernel.org/locking/index.html + 22. https://docs.kernel.org/subsystem-apis.html#human-interfaces + 23. https://docs.kernel.org/subsystem-apis.html#networking-interfaces + 24. https://docs.kernel.org/subsystem-apis.html#storage-interfaces + 25. https://docs.kernel.org/locking/index.html + 26. https://docs.kernel.org/process/license-rules.html + 27. https://docs.kernel.org/doc-guide/index.html + 28. https://docs.kernel.org/dev-tools/index.html + 29. https://docs.kernel.org/dev-tools/testing-overview.html + 30. https://docs.kernel.org/kernel-hacking/index.html + 31. https://docs.kernel.org/trace/index.html + 32. https://docs.kernel.org/fault-injection/index.html + 33. https://docs.kernel.org/livepatch/index.html + 34. https://docs.kernel.org/rust/index.html + 35. https://docs.kernel.org/admin-guide/index.html + 36. https://docs.kernel.org/kbuild/index.html + 37. https://docs.kernel.org/admin-guide/reporting-issues.html + 38. https://docs.kernel.org/tools/index.html + 39. https://docs.kernel.org/userspace-api/index.html + 40. https://docs.kernel.org/firmware-guide/index.html + 41. https://docs.kernel.org/devicetree/index.html + 42. https://docs.kernel.org/arch/index.html + 43. https://docs.kernel.org/staging/index.html + 44. https://docs.kernel.org/translations/index.html + 45. https://docs.kernel.org/_sources/power/s2ram.rst.txt + 46. https://docs.kernel.org/power/s2ram.html#how-to-get-s2ram-working + 47. https://docs.kernel.org/power/tricks.html + 48. https://docs.kernel.org/power/video.html + 49. https://docs.kernel.org/power/s2ram.html#using-trace-resume + 50. https://docs.kernel.org/power/s2ram.html#note + 51. http://sphinx-doc.org/ + 52. https://github.com/bitprophet/alabaster + 53. https://docs.kernel.org/_sources/power/s2ram.rst.txt |