From: ronald.wahl@raritan.com (Ronald Wahl)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] spi: atmel: fix corruption caused by too early transfer completion
Date: Thu, 07 Aug 2014 01:33:04 +0200 [thread overview]
Message-ID: <53E2BB30.1020009@raritan.com> (raw)
On 2014-08-06 13:00, Ronald Wahl wrote:
> The PDC (peripheral DMA controller) on AT91 supports two transfer
> counters and associated registers - one for current and one for the
> next transfer. If the current transfer is done the next transfer is
> moved into the current transfer. Now there are two interrupts: one is
> raised whenever a single transfer is done (ENDRX) and the other one is
> raised when the current and the next transfer has finished (RXBUFF).
> The issue is that the driver only enables the ENDRX interrupt which may
> lead to queuing a new request while there is still a transfer running.
> This can lead to overruns and/or corruption. By using the RXBUFF
> interrupt only we queue new requests only when the hardware queue is
> empty avoiding this problem.
Forgot to Cc: Nicolas Ferre ...
- ron
next reply other threads:[~2014-08-06 23:33 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-06 23:33 Ronald Wahl [this message]
-- strict thread matches above, loose matches on Subject: below --
2014-08-06 13:00 [PATCH] spi: atmel: fix corruption caused by too early transfer completion Ronald Wahl
2014-08-13 1:20 ` Yang, Wenyou
2014-08-13 6:16 ` Ludovic Desroches
2014-08-13 7:05 ` Yang, Wenyou
2014-08-13 8:13 ` Desroches, Ludovic
2014-08-13 8:26 ` Ronald Wahl
2014-08-13 9:16 ` Ludovic Desroches
2014-08-13 9:38 ` Ronald Wahl
2014-08-13 13:58 ` Ludovic Desroches
2014-08-13 8:20 ` Ronald Wahl
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=53E2BB30.1020009@raritan.com \
--to=ronald.wahl@raritan.com \
--cc=linux-arm-kernel@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.