Re: [2/3] powerpc/powernv: Fix OPAL RTC driver OPAL_BUSY loops

2018-04-26 Thread Michael Ellerman
On Tue, 2018-04-10 at 11:49:32 UTC, Nicholas Piggin wrote: > The OPAL RTC driver does not sleep in case it gets OPAL_BUSY or > OPAL_BUSY_EVENT from firmware, which causes large scheduling > latencies, up to 50 seconds have been observed here when RTC stops > responding (BMC reboot can do it). > >

Re: [PATCH 2/3] powerpc/powernv: Fix OPAL RTC driver OPAL_BUSY loops

2018-04-25 Thread Alexandre Belloni
On 25/04/2018 13:28:27+1000, Michael Ellerman wrote: > Alexandre Belloni writes: > > On 10/04/2018 23:01:36+1000, Nicholas Piggin wrote: > >> On Tue, 10 Apr 2018 14:07:28 +0200 > >> Alexandre Belloni wrote: > >> > > Fixes ("powerpc/powernv: Add RTC and NVRAM support plus RTAS > >> > > fallback

Re: [PATCH 2/3] powerpc/powernv: Fix OPAL RTC driver OPAL_BUSY loops

2018-04-24 Thread Michael Ellerman
Alexandre Belloni writes: > On 10/04/2018 23:01:36+1000, Nicholas Piggin wrote: >> On Tue, 10 Apr 2018 14:07:28 +0200 >> Alexandre Belloni wrote: >> > > Fixes ("powerpc/powernv: Add RTC and NVRAM support plus RTAS >> > > fallbacks" >> > > Cc: Benjamin Herrenschmidt >> > > Cc: linux-...@vger

Re: [PATCH 2/3] powerpc/powernv: Fix OPAL RTC driver OPAL_BUSY loops

2018-04-24 Thread Alexandre Belloni
On 10/04/2018 23:01:36+1000, Nicholas Piggin wrote: > On Tue, 10 Apr 2018 14:07:28 +0200 > Alexandre Belloni wrote: > > > Fixes ("powerpc/powernv: Add RTC and NVRAM support plus RTAS > > > fallbacks" > > > Cc: Benjamin Herrenschmidt > > > Cc: linux-...@vger.kernel.org > > > Signed-off-by: N

Re: [PATCH 2/3] powerpc/powernv: Fix OPAL RTC driver OPAL_BUSY loops

2018-04-10 Thread Nicholas Piggin
On Tue, 10 Apr 2018 14:07:28 +0200 Alexandre Belloni wrote: > Hi Nicholas, > > I would greatly appreciate a changelog and at least the cover letter > because it is difficult to grasp how this relates to the previous > patches you sent to the RTC mailing list. Yes good point. Basically this cha

Re: [PATCH 2/3] powerpc/powernv: Fix OPAL RTC driver OPAL_BUSY loops

2018-04-10 Thread Alexandre Belloni
Hi Nicholas, I would greatly appreciate a changelog and at least the cover letter because it is difficult to grasp how this relates to the previous patches you sent to the RTC mailing list. On 10/04/2018 21:49:32+1000, Nicholas Piggin wrote: > The OPAL RTC driver does not sleep in case it gets O

[PATCH 2/3] powerpc/powernv: Fix OPAL RTC driver OPAL_BUSY loops

2018-04-10 Thread Nicholas Piggin
The OPAL RTC driver does not sleep in case it gets OPAL_BUSY or OPAL_BUSY_EVENT from firmware, which causes large scheduling latencies, up to 50 seconds have been observed here when RTC stops responding (BMC reboot can do it). Fix this by converting it to the standard form OPAL_BUSY loop that slee