From: Marc Zyngier <maz@kernel.org>
To: Maxime Ripard <maxime@cerno.tech>
Cc: Florian Fainelli <f.fainelli@gmail.com>,
Dave Stevenson <dave.stevenson@raspberrypi.com>,
David Airlie <airlied@linux.ie>,
Nicolas Saenz Julienne <nsaenzjulienne@suse.de>,
LKML <linux-kernel@vger.kernel.org>,
DRI Development <dri-devel@lists.freedesktop.org>,
bcm-kernel-feedback-list@broadcom.com,
linux-rpi-kernel@lists.infradead.org,
Thomas Zimmermann <tzimmermann@suse.de>,
Hans Verkuil <hverkuil-cisco@xs4all.nl>,
Daniel Vetter <daniel.vetter@intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Mauro Carvalho Chehab <mchehab@kernel.org>,
linux-arm-kernel@lists.infradead.org,
Linux Media Mailing List <linux-media@vger.kernel.org>
Subject: Re: [PATCH v2 14/15] ARM: dts: bcm2711: Add the BSC interrupt controller
Date: Wed, 10 Feb 2021 15:30:45 +0000 [thread overview]
Message-ID: <9d868bf76072fee7838b6f2ff73a575c@kernel.org> (raw)
In-Reply-To: <20210210144043.s4plyc7ekwnnu7k4@gilmour>
Hi Maxime,
On 2021-02-10 14:40, Maxime Ripard wrote:
> Hi Dave,
>
> On Tue, Feb 09, 2021 at 09:49:05AM +0000, Dave Stevenson wrote:
>> On Mon, 11 Jan 2021 at 14:23, Maxime Ripard <maxime@cerno.tech> wrote:
>> >
>> > The BSC controllers used for the HDMI DDC have an interrupt controller
>> > shared between both instances. Let's add it to avoid polling.
>>
>> This seems to have unintended side effects.
>> GIC interrupt 117 is shared between the standard I2C controllers
>> (i2c-bcm2835) and the l2-intc block handling the HDMI I2C interrupts.
>>
>> Whilst i2c-bcm2835 requests the interrupt with IRQF_SHARED, that
>> doesn't appear to be an option for l2-intc registering as an interrupt
>> controller. i2c-bcm2835 therefore loses out and fails to register for
>> the interrupt.
>>
>> Is there an equivalent flag that an interrupt controller can add to
>> say that the parent interrupt is shared? Is that even supported?
>
> Indeed, it looks like setting an equivalent to IRQF_SHARED would be the
> solution, but I couldn't find anything that would allow us to in the
> irqchip code.
>
> Marc, Thomas, is it something that is allowed?
No, not really. That's because the chained handler is actually an
interrupt flow, and not a normal handler. IRQF_SHARED acts at the wrong
level for that.
I can see two possibilities:
- the l2-intc gets turned into a normal handler, and does the demux
from there. Horrible stuff.
- the i2c controller gets parented to the l2c-int as a fake interrupt,
and gets called from there. Horrible stuff.
Pick your poison... :-/
M.
--
Jazz is not dead. It just smells funny...
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
next prev parent reply other threads:[~2021-02-10 15:30 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-11 14:22 [PATCH v2 00/15] drm/vc4: hdmi: Add CEC support for the BCM2711 Maxime Ripard
2021-01-11 14:22 ` [PATCH v2 01/15] ARM: bcm: Select BRCMSTB_L2_IRQ for bcm2835 Maxime Ripard
2021-01-11 16:54 ` Florian Fainelli
2021-01-11 17:12 ` Nicolas Saenz Julienne
2021-01-11 14:22 ` [PATCH v2 02/15] drm/vc4: hdmi: Move hdmi reset to bind Maxime Ripard
2021-01-11 14:22 ` [PATCH v2 03/15] drm/vc4: hdmi: Fix register offset with longer CEC messages Maxime Ripard
2021-01-11 14:22 ` [PATCH v2 04/15] drm/vc4: hdmi: Fix up CEC registers Maxime Ripard
2021-01-11 14:22 ` [PATCH v2 05/15] drm/vc4: hdmi: Restore cec physical address on reconnect Maxime Ripard
2021-01-22 10:31 ` Dave Stevenson
2021-01-11 14:23 ` [PATCH v2 06/15] drm/vc4: hdmi: Compute the CEC clock divider from the clock rate Maxime Ripard
2021-01-11 14:23 ` [PATCH v2 07/15] drm/vc4: hdmi: Update the CEC clock divider on HSM rate change Maxime Ripard
2021-01-11 14:23 ` [PATCH v2 08/15] drm/vc4: hdmi: Introduce a CEC clock Maxime Ripard
2021-01-11 14:23 ` [PATCH v2 09/15] drm/vc4: hdmi: Split the interrupt handlers Maxime Ripard
2021-01-22 13:01 ` Dave Stevenson
2021-01-11 14:23 ` [PATCH v2 10/15] drm/vc4: hdmi: Support BCM2711 CEC interrupt setup Maxime Ripard
2021-01-22 13:10 ` Dave Stevenson
2021-01-11 14:23 ` [PATCH v2 11/15] drm/vc4: hdmi: Remove cec_available flag Maxime Ripard
2021-01-11 14:23 ` [PATCH v2 12/15] drm/vc4: hdmi: Don't register the CEC adapter if there's no interrupts Maxime Ripard
2021-01-11 14:23 ` [PATCH v2 13/15] dt-binding: display: bcm2711-hdmi: Add CEC and hotplug interrupts Maxime Ripard
2021-01-22 13:28 ` Dave Stevenson
2021-02-01 18:56 ` Rob Herring
2021-02-18 14:54 ` Rob Herring
2021-01-11 14:23 ` [PATCH v2 14/15] ARM: dts: bcm2711: Add the BSC interrupt controller Maxime Ripard
2021-02-09 9:49 ` Dave Stevenson
2021-02-10 14:40 ` Maxime Ripard
2021-02-10 15:30 ` Marc Zyngier [this message]
2021-02-10 15:49 ` Dave Stevenson
2021-02-10 18:49 ` Florian Fainelli
2021-02-12 11:20 ` Nicolas Saenz Julienne
2021-02-12 11:34 ` Maxime Ripard
2021-01-11 14:23 ` [PATCH v2 15/15] ARM: dts: bcm2711: Add the CEC " Maxime Ripard
2021-01-28 14:51 ` Nicolas Saenz Julienne
2021-01-12 15:24 ` [PATCH v2 00/15] drm/vc4: hdmi: Add CEC support for the BCM2711 Hans Verkuil
2021-01-18 13:55 ` Hans Verkuil
2021-01-27 15:28 ` Hans Verkuil
2021-01-25 21:03 ` Nicolas Saenz Julienne
2021-01-28 9:48 ` Maxime Ripard
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=9d868bf76072fee7838b6f2ff73a575c@kernel.org \
--to=maz@kernel.org \
--cc=airlied@linux.ie \
--cc=bcm-kernel-feedback-list@broadcom.com \
--cc=daniel.vetter@intel.com \
--cc=dave.stevenson@raspberrypi.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=f.fainelli@gmail.com \
--cc=hverkuil-cisco@xs4all.nl \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-rpi-kernel@lists.infradead.org \
--cc=maxime@cerno.tech \
--cc=mchehab@kernel.org \
--cc=nsaenzjulienne@suse.de \
--cc=tglx@linutronix.de \
--cc=tzimmermann@suse.de \
/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).