All of
 help / color / mirror / Atom feed
From: Julien Massot <>
To: Arnaud Pouliquen <>,
	Bjorn Andersson <>,
	Ohad Ben-Cohen <>,
	Mathieu Poirier <>
Subject: Re: [PATCH 0/4] rpmsg: char: introduce the rpmsg-raw channel
Date: Tue, 8 Jun 2021 11:08:13 +0200	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>


On 6/7/21 7:30 PM, Arnaud Pouliquen wrote:
> Purpose:
>    Allow the remote processor to instantiate a /dev/rpmsgX interface relying on the NS announcement
>    of the "rpmsg-raw" service.
>    This patchet is extracted from  the series [1] with rework to add rpmsg_create_default_ept helper.
> Aim:
>    There is no generic sysfs interface based on RPMsg that allows a user application to communicate
>    with a remote processor in a simple way.
>    The rpmsg_char dev solves a part of this problem by allowing an endpoint to be created on the
>    local side. But it does not take advantage of the NS announcement mechanism implemented for some
>    backends such as the virtio backend. So it is not possible to probe it from  a remote initiative.
>    Extending the char rpmsg device to support NS announcement makes the rpmsg_char more generic.
>    By announcing a "rpmg-raw" service, the firmware of a remote processor will be able to
>    instantiate a /dev/rpmsgX interface providing to the user application a basic link to communicate
>    with it without any knowledge of the rpmsg protocol.
> Implementation details:
>    - Register a rpmsg driver for the rpmsg_char driver, associated to the "rpmsg-raw" channel service.
>    - In case of rpmsg char device instantiated by the rpmsg bus (on NS announcement) manage the
>      channel default endpoint to ensure a stable default endpoint address, for communication with
>      the remote processor.
> How to test it:
>    - This series can be applied on git/andersson/remoteproc.git for-next branch (dc0e14fa833b)
>      + the "Restructure the rpmsg char to decorrelate the control part" series[2]
> [1]
> [2]

Just tested this whole series on remoteproc for-next branch + [2].
Works for me, /dev/rpmsg0 is created on NS announcement, and removed when stopping the remote processor.
I can do a repeated series of open /read/write/close, and got EBUSY if I try to open it more than once
at a time.

Firmware used for testing is derived from:
#define RPMSG_CHAN_NAME "rpmsg-raw"

Thanks Arnaud for your work.

Tested-by: Julien Massot <>

Julien Massot []

  parent reply	other threads:[~2021-06-08  9:08 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-07 17:30 [PATCH 0/4] rpmsg: char: introduce the rpmsg-raw channel Arnaud Pouliquen
2021-06-07 17:30 ` [PATCH 1/4] rpmsg: Introduce rpmsg_create_default_ept function Arnaud Pouliquen
2021-06-21 22:42   ` Mathieu Poirier
2021-06-07 17:30 ` [PATCH 2/4] rpmsg: char: Add possibility to create and reuse default endpoint Arnaud Pouliquen
2021-06-07 17:30 ` [PATCH 3/4] rpmsg: char: Introduce the "rpmsg-raw" channel Arnaud Pouliquen
2021-06-15 20:01   ` Mathieu Poirier
2021-06-16 12:38     ` Arnaud POULIQUEN
2021-06-17 21:31       ` Mathieu Poirier
2021-06-18 11:35         ` Arnaud POULIQUEN
2021-06-21 22:38           ` Mathieu Poirier
2021-06-22  8:21             ` Arnaud POULIQUEN
2021-06-22 20:30               ` Mathieu Poirier
2021-06-07 17:30 ` [PATCH 4/4] rpmsg: char: Return error if user tries to destroy a default endpoint Arnaud Pouliquen
2021-06-08  9:08 ` Julien Massot [this message]
2021-06-08 14:26 ` [PATCH 0/4] rpmsg: char: introduce the rpmsg-raw channel Mathieu Poirier
2021-06-08 15:27   ` Arnaud POULIQUEN

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:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \ \ \ \ \

* 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.