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From: olof@lixom•net (Olof Johansson)
To: Gabriel Paubert <paubert@iram•es>
Cc: linuxppc-dev@ozlabs•org
Subject: Re: [patch 27/35] Work around errata 4290
Date: Thu, 5 Jul 2007 14:26:44 -0500	[thread overview]
Message-ID: <20070705192644.GA17491@lixom.net> (raw)
In-Reply-To: <20070705185021.GA26069@iram.es>

On Thu, Jul 05, 2007 at 08:50:21PM +0200, Gabriel Paubert wrote:
> On Thu, Jul 05, 2007 at 12:03:00PM -0500, Olof Johansson wrote:
> > Workaround for errata 4290: The decrementer ticks at half the expected rate
> > so load it with half the value it would otherwise be loaded with.
> > 
> > 
> > Index: 2.6.21/include/asm-powerpc/time.h
> > ===================================================================
> > --- 2.6.21.orig/include/asm-powerpc/time.h
> > +++ 2.6.21/include/asm-powerpc/time.h
> > @@ -173,6 +173,13 @@ static inline unsigned int get_dec(void)
> >  
> >  static inline void set_dec(int val)
> >  {
> > +#ifdef CONFIG_PPC_PASEMI
> > +	/* PA6T rev Ax have decrementer ticking at 1/2 tb rate */
> > +	val >>= 2;
> 
> Comment does not match code: looks like a divide by 4 to me!

You're right. Thanks for catching it.

Never caught it because the timer code behaves just fine anyway, but
it'll waste power by waking up twice as often when idle.


-Olof

  reply	other threads:[~2007-07-05 19:15 UTC|newest]

Thread overview: 46+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-07-05 17:02 [patch 00/35] PA Semi patch set Olof Johansson
2007-07-05 17:02 ` [patch 01/35] pasemi: rename platform Olof Johansson
2007-07-08 23:52   ` Stephen Rothwell
2007-07-09  0:18     ` Olof Johansson
2007-07-09  7:23       ` Stephen Rothwell
2007-07-09 17:19         ` Olof Johansson
2007-07-09 17:21           ` Olof Johansson
2007-07-05 17:02 ` [patch 02/35] PA Semi EDAC driver Olof Johansson
2007-07-05 17:02 ` [patch 03/35] Change powerpc64 ioaddr_t to u_int Olof Johansson
2007-07-05 17:02 ` [patch 04/35] pasemi_mac: Fix TX interrupt threshold Olof Johansson
2007-07-05 17:02 ` [patch 05/35] pasemi_mac: Clean TX ring in poll Olof Johansson
2007-07-05 17:02 ` [patch 06/35] pasemi_mac: Abstract out register access Olof Johansson
2007-07-05 17:02 ` [patch 07/35] pasemi_mac: stop using the pci config space accessors for register read/writes Olof Johansson
2007-07-26 21:25   ` Marian Balakowicz
2007-07-28  8:35     ` Olof Johansson
2007-08-01  9:27       ` Marian Balakowicz
2007-07-05 17:02 ` [patch 08/35] pasemi_mac: Enable L2 caching of packet headers Olof Johansson
2007-07-05 17:02 ` [patch 09/35] pasemi_mac: Simplify memcpy for short receives Olof Johansson
2007-07-05 17:02 ` [patch 10/35] pasemi_mac: Minor performance tweaks Olof Johansson
2007-07-05 17:02 ` [patch 11/35] pasemi_mac: Reduce locking when cleaning TX ring Olof Johansson
2007-07-05 17:02 ` [patch 12/35] pasemi_mac: Enable LLTX Olof Johansson
2007-07-05 17:02 ` [patch 13/35] Cleanup marvell phy driver init Olof Johansson
2007-07-05 17:02 ` [patch 14/35] Add 88E1112 PHY ID to the marvell driver Olof Johansson
2007-07-05 17:02 ` [patch 15/35] Export HID registers via sysfs Olof Johansson
2007-07-05 17:02 ` [patch 16/35] Electra ide platform glue Olof Johansson
2007-07-05 17:02 ` [patch 17/35] CF driver for PA Semi Electra Olof Johansson
2007-07-05 17:02 ` [patch 18/35] Spread IRQs among cpus by default Olof Johansson
2007-07-05 17:02 ` [patch 19/35] Improve machine check output Olof Johansson
2007-07-05 17:02 ` [patch 20/35] Remove idle_spin function pointer Olof Johansson
2007-07-05 17:02 ` [patch 21/35] Use MSR_PMM to disable profiling of the idle loop Olof Johansson
2007-07-05 17:02 ` [patch 22/35] Work around errata 4111 Olof Johansson
2007-07-05 17:02 ` [patch 23/35] Work around UART erratas Olof Johansson
2007-07-05 17:02 ` [patch 24/35] Work around errata 4628 Olof Johansson
2007-07-05 17:02 ` [patch 25/35] Work around errata 4025 Olof Johansson
2007-07-05 17:02 ` [patch 26/35] Work around errata 4713 Olof Johansson
2007-07-05 17:03 ` [patch 27/35] Work around errata 4290 Olof Johansson
2007-07-05 18:50   ` Gabriel Paubert
2007-07-05 19:26     ` Olof Johansson [this message]
2007-07-05 17:03 ` [patch 28/35] Work around errata 4712 Olof Johansson
2007-07-05 17:03 ` [patch 29/35] Work around errata 4910 Olof Johansson
2007-07-05 17:03 ` [patch 30/35] Disable PURR on pa6t Olof Johansson
2007-07-05 17:03 ` [patch 31/35] Work around errata 4161 Olof Johansson
2007-07-05 17:03 ` [patch 32/35] Dont reset openpic on init Olof Johansson
2007-07-05 17:03 ` [patch 33/35] Work around errata 5667 Olof Johansson
2007-07-05 17:03 ` [patch 34/35] Work around errata 4505 Olof Johansson
2007-07-05 17:03 ` [patch 35/35] Work around errata 5652 Olof Johansson

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