From: Arnd Bergmann <arnd@arndb.de>
To: Magnus Damm <magnus.damm@gmail.com>
Cc: "Russell King - ARM Linux" <linux@arm.linux.org.uk>,
Magnus Damm <damm@opensource.se>,
linux-pci@vger.kernel.org,
Simon Horman <horms+renesas@verge.net.au>,
"linux-kernel" <linux-kernel@vger.kernel.org>,
Bjorn Helgaas <bhelgaas@google.com>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>,
"SH-Linux" <linux-sh@vger.kernel.org>,
Ben Dooks <ben-linux@fluff.org>,
Santosh Shilimkar <santosh.shilimkar@ti.com>
Subject: Re: DMABOUNCE in pci-rcar
Date: Tue, 25 Feb 2014 16:44:01 +0100 [thread overview]
Message-ID: <201402251644.01463.arnd@arndb.de> (raw)
In-Reply-To: <CANqRtoSsra-NQF_4dz1iBjzEvdaUco9o3gbPi_6rEgswV=maCw@mail.gmail.com>
On Tuesday 25 February 2014, Magnus Damm wrote:
> And the DMABOUNCE code does not support HIGHMEM, so because of that
> the block layer BOUNCE is also used.
Ah, I misunderstood this part previously. I understand better what's
going on now, but this also enforces the impression that both BOUNCE
and DMABOUNCE are not what you should be doing here.
On a related note, I've had some more discussions with Santosh on IRC,
and I think he's in the exact same position on mach-keystone, so we
should make sure that whatever solution either of you comes up with
also works for the other one.
The situation on keystone may be a little worse even, because all their
DMA masters have a 2GB limit, but it's also possible that the same
is true for you. Which categories of DMA masters do you have on R-Car?
a) less than 32-bit mask, with IOMMU
b) less than 32-bit mask, without IOMMU
c) 32-bit mask
d) 64-bit mask
Arnd
WARNING: multiple messages have this Message-ID (diff)
From: Arnd Bergmann <arnd@arndb.de>
To: linux-arm-kernel@lists.infradead.org
Subject: Re: DMABOUNCE in pci-rcar
Date: Tue, 25 Feb 2014 15:44:01 +0000 [thread overview]
Message-ID: <201402251644.01463.arnd@arndb.de> (raw)
In-Reply-To: <CANqRtoSsra-NQF_4dz1iBjzEvdaUco9o3gbPi_6rEgswV=maCw@mail.gmail.com>
On Tuesday 25 February 2014, Magnus Damm wrote:
> And the DMABOUNCE code does not support HIGHMEM, so because of that
> the block layer BOUNCE is also used.
Ah, I misunderstood this part previously. I understand better what's
going on now, but this also enforces the impression that both BOUNCE
and DMABOUNCE are not what you should be doing here.
On a related note, I've had some more discussions with Santosh on IRC,
and I think he's in the exact same position on mach-keystone, so we
should make sure that whatever solution either of you comes up with
also works for the other one.
The situation on keystone may be a little worse even, because all their
DMA masters have a 2GB limit, but it's also possible that the same
is true for you. Which categories of DMA masters do you have on R-Car?
a) less than 32-bit mask, with IOMMU
b) less than 32-bit mask, without IOMMU
c) 32-bit mask
d) 64-bit mask
Arnd
WARNING: multiple messages have this Message-ID (diff)
From: arnd@arndb.de (Arnd Bergmann)
To: linux-arm-kernel@lists.infradead.org
Subject: DMABOUNCE in pci-rcar
Date: Tue, 25 Feb 2014 16:44:01 +0100 [thread overview]
Message-ID: <201402251644.01463.arnd@arndb.de> (raw)
In-Reply-To: <CANqRtoSsra-NQF_4dz1iBjzEvdaUco9o3gbPi_6rEgswV=maCw@mail.gmail.com>
On Tuesday 25 February 2014, Magnus Damm wrote:
> And the DMABOUNCE code does not support HIGHMEM, so because of that
> the block layer BOUNCE is also used.
Ah, I misunderstood this part previously. I understand better what's
going on now, but this also enforces the impression that both BOUNCE
and DMABOUNCE are not what you should be doing here.
On a related note, I've had some more discussions with Santosh on IRC,
and I think he's in the exact same position on mach-keystone, so we
should make sure that whatever solution either of you comes up with
also works for the other one.
The situation on keystone may be a little worse even, because all their
DMA masters have a 2GB limit, but it's also possible that the same
is true for you. Which categories of DMA masters do you have on R-Car?
a) less than 32-bit mask, with IOMMU
b) less than 32-bit mask, without IOMMU
c) 32-bit mask
d) 64-bit mask
Arnd
next prev parent reply other threads:[~2014-02-25 15:44 UTC|newest]
Thread overview: 72+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-24 11:00 DMABOUNCE in pci-rcar Arnd Bergmann
2014-02-24 11:00 ` Arnd Bergmann
2014-02-24 11:00 ` Arnd Bergmann
2014-02-24 23:49 ` Magnus Damm
2014-02-24 23:49 ` Magnus Damm
2014-02-24 23:49 ` Magnus Damm
2014-02-25 0:17 ` Russell King - ARM Linux
2014-02-25 0:17 ` Russell King - ARM Linux
2014-02-25 0:17 ` Russell King - ARM Linux
2014-02-25 2:00 ` Magnus Damm
2014-02-25 2:00 ` Magnus Damm
2014-02-25 2:00 ` Magnus Damm
2014-02-25 15:44 ` Arnd Bergmann [this message]
2014-02-25 15:44 ` Arnd Bergmann
2014-02-25 15:44 ` Arnd Bergmann
2014-02-25 12:15 ` Arnd Bergmann
2014-02-25 12:15 ` Arnd Bergmann
2014-02-25 12:15 ` Arnd Bergmann
2014-02-26 19:48 ` Bjorn Helgaas
2014-02-26 19:48 ` Bjorn Helgaas
2014-02-26 19:48 ` Bjorn Helgaas
2014-02-26 19:57 ` Arnd Bergmann
2014-02-26 19:57 ` Arnd Bergmann
2014-02-26 19:57 ` Arnd Bergmann
2014-02-26 21:02 ` Bjorn Helgaas
2014-02-26 21:02 ` Bjorn Helgaas
2014-02-26 21:02 ` Bjorn Helgaas
2014-02-26 21:52 ` Arnd Bergmann
2014-02-26 21:52 ` Arnd Bergmann
2014-02-26 21:52 ` Arnd Bergmann
2014-03-20 15:04 ` Ben Dooks
2014-03-20 15:04 ` Ben Dooks
2014-03-20 15:04 ` Ben Dooks
2014-03-20 15:26 ` Russell King - ARM Linux
2014-03-20 15:26 ` Russell King - ARM Linux
2014-03-20 15:26 ` Russell King - ARM Linux
2014-03-20 15:36 ` Ben Dooks
2014-03-20 15:36 ` Ben Dooks
2014-03-20 15:36 ` Ben Dooks
2014-03-20 16:09 ` Arnd Bergmann
2014-03-20 16:09 ` Arnd Bergmann
2014-03-20 16:09 ` Arnd Bergmann
2014-03-20 16:12 ` Ben Dooks
2014-03-20 16:12 ` Ben Dooks
2014-03-20 16:12 ` Ben Dooks
2014-03-20 16:41 ` Arnd Bergmann
2014-03-20 16:41 ` Arnd Bergmann
2014-03-20 16:41 ` Arnd Bergmann
2014-03-20 17:25 ` Ben Dooks
2014-03-20 17:25 ` Ben Dooks
2014-03-20 17:25 ` Ben Dooks
2014-03-20 17:31 ` Jason Gunthorpe
2014-03-20 17:31 ` Jason Gunthorpe
2014-03-20 17:31 ` Jason Gunthorpe
2014-03-20 17:32 ` Ben Dooks
2014-03-20 17:32 ` Ben Dooks
2014-03-20 17:32 ` Ben Dooks
2014-03-20 18:29 ` Arnd Bergmann
2014-03-20 18:29 ` Arnd Bergmann
2014-03-20 18:29 ` Arnd Bergmann
2014-03-20 18:39 ` Russell King - ARM Linux
2014-03-20 18:39 ` Russell King - ARM Linux
2014-03-20 18:39 ` Russell King - ARM Linux
2014-03-20 19:04 ` Geert Uytterhoeven
2014-03-20 19:04 ` Geert Uytterhoeven
2014-03-20 19:04 ` Geert Uytterhoeven
2014-03-20 22:11 ` Arnd Bergmann
2014-03-20 22:11 ` Arnd Bergmann
2014-03-20 22:11 ` Arnd Bergmann
2014-03-20 22:50 ` Russell King - ARM Linux
2014-03-20 22:50 ` Russell King - ARM Linux
2014-03-20 22:50 ` Russell King - ARM Linux
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=201402251644.01463.arnd@arndb.de \
--to=arnd@arndb.de \
--cc=ben-linux@fluff.org \
--cc=bhelgaas@google.com \
--cc=damm@opensource.se \
--cc=horms+renesas@verge.net.au \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=linux-sh@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=magnus.damm@gmail.com \
--cc=santosh.shilimkar@ti.com \
/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.