From: Lucas Stach <l.stach@pengutronix.de>
To: Antony Pavlov <antonynpavlov@gmail.com>
Cc: barebox@lists.infradead.org
Subject: Re: [PATCH] net: rtl8169: remove unnecessary cache maintenance
Date: Tue, 06 Jan 2015 12:11:34 +0100 [thread overview]
Message-ID: <1420542694.2333.11.camel@pengutronix.de> (raw)
In-Reply-To: <20150106135611.e7d20dffcf2f94ee0ccfbdaa@gmail.com>
Am Dienstag, den 06.01.2015, 13:56 +0300 schrieb Antony Pavlov:
> On Mon, 05 Jan 2015 18:37:29 +0100
> Lucas Stach <dev@lynxeye.de> wrote:
>
> > Am Montag, den 05.01.2015, 20:19 +0300 schrieb Antony Pavlov:
> > > On Sun, 4 Jan 2015 22:09:05 +0100
> > > Lucas Stach <dev@lynxeye.de> wrote:
> > >
> > > I suppose that this patch can make problems on MIPS with explicid cache handling.
> > >
> > How would it?
> > This driver is ARM only for now (as we are using ARM MMU functions to
> > flush buffers) until someone gets around to properly implement generic
> > dma sync ops.
>
> Anyway it is reasonable to add 'depends on ARM' to 'config DRIVER_NET_RTL8169'
> record in drivers/net/Kconfig.
>
Yes, will do.
> > But even then MIPS knows about uncached memory types which is exactly
> > what should be returned for a dma coherent memory allocation.
>
> Alas! We can't just add 'volatile' modifier to make pointer uncached on MIPS in general case.
This is not how it works. The memory for the buffer descriptors isn't
general malloc memory, but allocated with dma_alloc_coherent, which
makes sure the memory is uncached. This works on both ARM and MIPS.
Regards,
Lucas
--
Pengutronix e.K. | Lucas Stach |
Industrial Linux Solutions | http://www.pengutronix.de/ |
_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox
prev parent reply other threads:[~2015-01-06 11:12 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-04 21:09 Lucas Stach
2015-01-05 11:52 ` Sascha Hauer
2015-01-05 17:19 ` Antony Pavlov
2015-01-05 17:37 ` Lucas Stach
2015-01-06 10:56 ` Antony Pavlov
2015-01-06 11:11 ` Lucas Stach [this message]
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=1420542694.2333.11.camel@pengutronix.de \
--to=l.stach@pengutronix.de \
--cc=antonynpavlov@gmail.com \
--cc=barebox@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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox