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* [PATCH] powerpc/powernv: Only delay opal_rtc_read() retry when necessary
@ 2015-12-18 10:46 Michael Neuling
  2015-12-21  0:06 ` Stewart Smith
  2016-01-11  9:14 ` Michael Ellerman
  0 siblings, 2 replies; 3+ messages in thread
From: Michael Neuling @ 2015-12-18 10:46 UTC (permalink / raw)
  To: Michael Ellerman, benh; +Cc: linuxppc-dev, Stewart Smith, Anton Blanchard

Only delay opal_rtc_read() when busy and are going to retry.

This has the advantage of possibly saving a massive 10ms off booting!

Kudos to Stewart for noticing.

Signed-off-by: Michael Neuling <mikey@neuling.org>

diff --git a/arch/powerpc/platforms/powernv/opal-rtc.c b/arch/powerpc/platf=
orms/powernv/opal-rtc.c
index 37dbee1..06511f3 100644
--- a/arch/powerpc/platforms/powernv/opal-rtc.c
+++ b/arch/powerpc/platforms/powernv/opal-rtc.c
@@ -51,7 +51,7 @@ unsigned long __init opal_get_boot_time(void)
 		rc =3D opal_rtc_read(&__y_m_d, &__h_m_s_ms);
 		if (rc =3D=3D OPAL_BUSY_EVENT)
 			opal_poll_events(NULL);
-		else
+		else if (rc =3D=3D OPAL_BUSY)
 			mdelay(10);
 	}
 	if (rc !=3D OPAL_SUCCESS)

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] powerpc/powernv: Only delay opal_rtc_read() retry when necessary
  2015-12-18 10:46 [PATCH] powerpc/powernv: Only delay opal_rtc_read() retry when necessary Michael Neuling
@ 2015-12-21  0:06 ` Stewart Smith
  2016-01-11  9:14 ` Michael Ellerman
  1 sibling, 0 replies; 3+ messages in thread
From: Stewart Smith @ 2015-12-21  0:06 UTC (permalink / raw)
  To: Michael Neuling, Michael Ellerman, benh; +Cc: linuxppc-dev, Anton Blanchard

Michael Neuling <mikey@neuling.org> writes:

> Only delay opal_rtc_read() when busy and are going to retry.
>
> This has the advantage of possibly saving a massive 10ms off booting!
>
> Kudos to Stewart for noticing.
>
> Signed-off-by: Michael Neuling <mikey@neuling.org>

Reviewed-by: Stewart Smith <stewart@linux.vnet.ibm.com>

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: powerpc/powernv: Only delay opal_rtc_read() retry when necessary
  2015-12-18 10:46 [PATCH] powerpc/powernv: Only delay opal_rtc_read() retry when necessary Michael Neuling
  2015-12-21  0:06 ` Stewart Smith
@ 2016-01-11  9:14 ` Michael Ellerman
  1 sibling, 0 replies; 3+ messages in thread
From: Michael Ellerman @ 2016-01-11  9:14 UTC (permalink / raw)
  To: Michael Neuling, benh; +Cc: Stewart Smith, linuxppc-dev, Anton Blanchard

On Fri, 2015-18-12 at 10:46:04 UTC, Michael Neuling wrote:
> Only delay opal_rtc_read() when busy and are going to retry.
> 
> This has the advantage of possibly saving a massive 10ms off booting!
> 
> Kudos to Stewart for noticing.
> 
> Signed-off-by: Michael Neuling <mikey@neuling.org>
> Reviewed-by: Stewart Smith <stewart@linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/57a9039052aadf5833c40ab494

cheers

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2016-01-11  9:14 UTC | newest]

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2015-12-18 10:46 [PATCH] powerpc/powernv: Only delay opal_rtc_read() retry when necessary Michael Neuling
2015-12-21  0:06 ` Stewart Smith
2016-01-11  9:14 ` Michael Ellerman

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