All of lore.kernel.org
 help / color / mirror / Atom feed
From: Marc Zyngier <maz@kernel.org>
To: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Marek Vasut <marex@denx.de>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Patrick Delaunay <patrick.delaunay@st.com>,
	linux-stm32@st-md-mailman.stormreply.com,
	Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: STM32MP1 level triggered interrupts
Date: Tue, 21 Jan 2020 17:21:38 +0000	[thread overview]
Message-ID: <82d4619107e9ac76d317268637f050cf@kernel.org> (raw)
In-Reply-To: <d6e02817-2464-51b9-246a-7720b607b8d6@st.com>

On 2020-01-21 17:12, Alexandre Torgue wrote:
> Hi Marek,
> 
> On 1/20/20 7:32 PM, Marek Vasut wrote:
>> Hi,
>> 
>> I have a device connected to STM32MP157C which requires active-low
>> level-triggered interrupt sink. The device interrupt line is connected
>> to the SoC gpio-C bank, which has it's interrupt line routed into 
>> EXTI,
>> which can only handle edge triggered interrupts to my understanding.
> 
> correct.
> 
>> 
>> However, ARM GIC should be able to do both and EXTI has this irqmux /
>> EXTImux functionality, which -- if my understanding is correct -- is
>> capable of routing a select GPIO line directly into the GIC as an 
>> EXTIn
>> interrupt signal. Thus, this might permit handling active low
>> level-triggered interrupts. Is there some DT binding to configure this 
>> yet ?
>> 
>> Or is there some other, better, way ?
>> 
> 
> For SPIs, GIC controller handles rising edge triggered interrupt and
> active high level-sensitive. GIC integration in STM32MP157c makes that
> only active high level-sensitive configuration for SPI interrupts is
> supported.

This statement is a slight exaggeration. *any* GIC will happily service
rising-edge triggered SPIs, as it is mandated by the spec. What I 
suspect
is that there is no SPI that is routed out of the SoC for anyone to 
directly
plug anything into it.

          M.
-- 
Jazz is not dead. It just smells funny...

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2020-01-21 17:21 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-20 18:32 STM32MP1 level triggered interrupts Marek Vasut
2020-01-21 17:12 ` Alexandre Torgue
2020-01-21 17:21   ` Marc Zyngier [this message]
2020-01-22 16:56     ` Alexandre Torgue
2020-01-21 17:41   ` Marek Vasut
2020-01-22 17:19     ` Alexandre Torgue
2020-01-22 19:29       ` Marek Vasut
2020-01-23  8:27         ` Alexandre Torgue
2020-01-23  9:22           ` Marc Zyngier
2020-01-23 10:12             ` Uwe Kleine-König
2020-01-23 10:44               ` Marc Zyngier
2020-01-23 10:52                 ` Uwe Kleine-König
2020-01-23 11:18                   ` Marc Zyngier
2020-01-23 22:21                     ` Marek Vasut
2020-01-24  9:17                       ` Alexandre Torgue
2020-01-24  9:24                         ` Marc Zyngier
2020-01-28 18:32                           ` Marek Vasut
2020-02-05 10:26                             ` Marek Vasut
2020-02-05 11:42                             ` Marc Zyngier
2020-02-05 11:53                               ` Marek Vasut
2020-02-05 12:32                                 ` Marc Zyngier
2020-02-05 15:36                                   ` Alexandre TORGUE
2020-02-06  2:00                                     ` Marek Vasut
2020-01-24 12:25                         ` Marek Vasut
2020-01-24  9:21                       ` Marc Zyngier
2020-01-24  9:35                         ` Alexandre Torgue
2020-01-23 22:21             ` Marek Vasut

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=82d4619107e9ac76d317268637f050cf@kernel.org \
    --to=maz@kernel.org \
    --cc=alexandre.torgue@st.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-stm32@st-md-mailman.stormreply.com \
    --cc=marex@denx.de \
    --cc=mcoquelin.stm32@gmail.com \
    --cc=patrick.delaunay@st.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.