[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-id: <45B3C5C9.4010007@shaw.ca>
Date: Sun, 21 Jan 2007 13:58:01 -0600
From: Robert Hancock <hancockr@...w.ca>
To: Björn Steinbrink <B.Steinbrink@....de>,
Robert Hancock <hancockr@...w.ca>,
Jeff Garzik <jeff@...zik.org>, Chr <chunkeey@....de>,
Alistair John Strachan <s0348365@....ed.ac.uk>,
linux-kernel@...r.kernel.org, htejun@...il.com,
jens.axboe@...cle.com, lwalton@...l.com
Subject: Re: SATA exceptions with 2.6.20-rc5
Björn Steinbrink wrote:
> All kernels were bad using that approach. So back to square 1. :/
>
> Björn
>
OK guys, here's a new patch to try against 2.6.20-rc5:
Right now when switching between ADMA mode and legacy mode (i.e. when
going from doing normal DMA reads/writes to doing a FLUSH CACHE) we just
set the ADMA GO register bit appropriately and continue with no delay.
It looks like in some cases the controller doesn't respond to this
immediately, it takes some nanoseconds for the controller's status
registers to reflect the change that was made. It's possible that if we
were trying to issue commands during this time, the controller might not
react properly. This patch adds some code to wait for the status
register to change to the state we asked for before continuing.
--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@...pamshaw.ca
Home Page: http://www.roberthancock.com/
View attachment "sata_nv-wait-for-response-on-adma-switch.patch" of type "text/plain" (1981 bytes)
Powered by blists - more mailing lists