diff options
author | David Vrabel <david.vrabel@csr.com> | 2008-10-20 16:07:19 +0100 |
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committer | David Vrabel <david.vrabel@csr.com> | 2008-10-20 16:07:19 +0100 |
commit | 61e0e79ee3c609eb34edf2fe023708cba6a79b1f (patch) | |
tree | 663deacffd4071120dc9badb70428fe5f124c7b9 /Documentation/power/s2ram.txt | |
parent | c15895ef30c2c03e99802951787183039a349d32 (diff) | |
parent | 0cfd81031a26717fe14380d18275f8e217571615 (diff) |
Merge branch 'master' into for-upstream
Conflicts:
Documentation/ABI/testing/sysfs-bus-usb
drivers/Makefile
Diffstat (limited to 'Documentation/power/s2ram.txt')
-rw-r--r-- | Documentation/power/s2ram.txt | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/Documentation/power/s2ram.txt b/Documentation/power/s2ram.txt index b05f512130e..2ebdc6091ce 100644 --- a/Documentation/power/s2ram.txt +++ b/Documentation/power/s2ram.txt @@ -54,3 +54,21 @@ 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 +==== +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. + +Consequence is that after a resume (even if it is successful) your system +clock will have a value corresponding to the magic mumber 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. |