From: rvaswani@codeaurora.org (rvaswani at codeaurora.org)
To: linux-arm-kernel@lists.infradead.org
Subject: [DT] API to determine if interrupt is PPI or SPI ?
Date: Fri, 27 Jul 2012 13:00:24 -0700 (PDT) [thread overview]
Message-ID: <8cdb3e7e9dc79635a130214cf6ba1dd4.squirrel@www.codeaurora.org> (raw)
In-Reply-To: <20120727130947.GN559@mudshark.cambridge.arm.com>
> On Fri, Jul 27, 2012 at 01:33:36PM +0100, Rob Herring wrote:
>> On 07/26/2012 02:18 PM, rvaswani at codeaurora.org wrote:
>> > Hello,
>> >
>> > We can specify the interrupt information in the device tree using the
>> arm
>> > gic convention.
>> > Is there an API to read directly the 1st cell and determine if an
>> > interrupt is a PPI or a SPI ? This information is directly relevant to
>> the
>> > driver because it needs to call request_irq or request_percpu_irq
>> based on
>> > this data.
>> >
>> > How should this be done ideally ?
>>
>> Seems a bit strange to me that you would have a h/w block that can be
>> connected either way...
>
> The CPU PMU can be wired as either SPI or PPI. The latter makes more sense
> to
> me but usually (although not exclusively) it's wired using the former.
>
> Will
>
We have the same driver for a hardware for different chipsets and
unfortunately the hardware team decided to connect this GIC interrupt
differently across these chipsets. This leaves us with a software choice
to make.
We could add another property to the device tree (like irq-is-percpu,
irq-is-not-percpu), but that seems redundant.
We were hoping to have an API to tell us the SPI/PPI difference since this
information is already encoded in the interrupt-cells in the device tree
for this device.
Would that be the right way to go or there is something better that can be
done ?
Thanks,
Rohit
--
Sent by a consultant of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.
prev parent reply other threads:[~2012-07-27 20:00 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-26 19:18 [DT] API to determine if interrupt is PPI or SPI ? rvaswani at codeaurora.org
2012-07-27 12:33 ` Rob Herring
2012-07-27 13:09 ` Will Deacon
2012-07-27 20:00 ` rvaswani at codeaurora.org [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=8cdb3e7e9dc79635a130214cf6ba1dd4.squirrel@www.codeaurora.org \
--to=rvaswani@codeaurora.org \
--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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).