rtc: Extend timeout for waiting for UIP to clear to 1s
authorMario Limonciello <mario.limonciello@amd.com>
Tue, 28 Nov 2023 05:36:53 +0000 (23:36 -0600)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 1 Feb 2024 00:18:56 +0000 (16:18 -0800)
commit49a76c08bcfc2260af9bf9975e9f770c6f46102a
tree0a2b8ae24eed321cdcb240437ea78e53e157d1ce
parent9d20185601a030266e222bd7a513984f28170e18
rtc: Extend timeout for waiting for UIP to clear to 1s

commit cef9ecc8e938dd48a560f7dd9be1246359248d20 upstream.

Specs don't say anything about UIP being cleared within 10ms. They
only say that UIP won't occur for another 244uS. If a long NMI occurs
while UIP is still updating it might not be possible to get valid
data in 10ms.

This has been observed in the wild that around s2idle some calls can
take up to 480ms before UIP is clear.

Adjust callers from outside an interrupt context to wait for up to a
1s instead of 10ms.

Cc: <stable@vger.kernel.org> # 6.1.y
Fixes: ec5895c0f2d8 ("rtc: mc146818-lib: extract mc146818_avoid_UIP")
Reported-by: Carsten Hatger <xmb8dsv4@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217626
Tested-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Reviewed-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Acked-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20231128053653.101798-5-mario.limonciello@amd.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/rtc.c
drivers/base/power/trace.c
drivers/rtc/rtc-cmos.c
drivers/rtc/rtc-mc146818-lib.c