dmaengine Archive on lore.kernel.org
 help / color / Atom feed
From: Rob Herring <robh+dt@kernel.org>
To: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc: devicetree@vger.kernel.org, Frank Rowand <frowand.list@gmail.com>,
	"moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" 
	<linux-arm-kernel@lists.infradead.org>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	linux-arm-msm <linux-arm-msm@vger.kernel.org>,
	"open list:DMA GENERIC OFFLOAD ENGINE SUBSYSTEM" 
	<dmaengine@vger.kernel.org>,
	etnaviv@lists.freedesktop.org,
	dri-devel <dri-devel@lists.freedesktop.org>,
	xen-devel@lists.xenproject.org, linux-tegra@vger.kernel.org,
	Linux Media Mailing List <linux-media@vger.kernel.org>,
	linux-pci@vger.kernel.org, Matthias Brugger <mbrugger@suse.com>,
	Robin Murphy <robin.murphy@arm.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	james.quinlan@broadcom.com, Stefan Wahren <wahrenst@gmx.net>,
	Dan Williams <dan.j.williams@intel.com>,
	freedreno <freedreno@lists.freedesktop.org>
Subject: Re: [PATCH 00/11] of: Fix DMA configuration for non-DT masters
Date: Tue, 24 Sep 2019 16:59:20 -0500
Message-ID: <CAL_Jsq+v+svTyna7UzQdRVqfNc5Z_bgWzxNRXv7-Wqv3NwDu2g@mail.gmail.com> (raw)
In-Reply-To: <20190924181244.7159-1-nsaenzjulienne@suse.de>

On Tue, Sep 24, 2019 at 1:12 PM Nicolas Saenz Julienne
<nsaenzjulienne@suse.de> wrote:
>
> Hi All,
> this series tries to address one of the issues blocking us from
> upstreaming Broadcom's STB PCIe controller[1]. Namely, the fact that
> devices not represented in DT which sit behind a PCI bus fail to get the
> bus' DMA addressing constraints.
>
> This is due to the fact that of_dma_configure() assumes it's receiving a
> DT node representing the device being configured, as opposed to the PCIe
> bridge node we currently pass. This causes the code to directly jump
> into PCI's parent node when checking for 'dma-ranges' and misses
> whatever was set there.
>
> To address this I create a new API in OF - inspired from Robin Murphys
> original proposal[2] - which accepts a bus DT node as it's input in
> order to configure a device's DMA constraints. The changes go deep into
> of/address.c's implementation, as a device being having a DT node
> assumption was pretty strong.
>
> On top of this work, I also cleaned up of_dma_configure() removing its
> redundant arguments and creating an alternative function for the special cases
> not applicable to either the above case or the default usage.
>
> IMO the resulting functions are more explicit. They will probably
> surface some hacky usages that can be properly fixed as I show with the
> DT fixes on the Layerscape platform.
>
> This was also tested on a Raspberry Pi 4 with a custom PCIe driver and
> on a Seattle AMD board.

Humm, I've been working on this issue too. Looks similar though yours
has a lot more churn and there's some other bugs I've found.

Can you test out this branch[1]. I don't have any h/w needing this,
but wrote a unittest and tested with modified QEMU.

Rob

[1] git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git dma-masks

  parent reply index

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-24 18:12 Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 01/11] of: address: clean-up unused variable in of_dma_get_range() Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 02/11] of: base: introduce __of_n_*_cells_parent() Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 03/11] of: address: use parent DT node in bus->count_cells() Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 04/11] of: address: introduce of_translate_dma_address_parent() Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 05/11] of: expose __of_get_dma_parent() to OF subsystem Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 06/11] of: address: use parent OF node in of_dma_get_range() Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 07/11] dts: arm64: layerscape: add dma-ranges property to qoric-mc node Nicolas Saenz Julienne
2019-10-14  8:28   ` Shawn Guo
2019-10-14 10:00     ` Nicolas Saenz Julienne
2019-10-14 11:09       ` Shawn Guo
2019-09-24 18:12 ` [PATCH 08/11] dts: arm64: layerscape: add dma-ranges property to pcie nodes Nicolas Saenz Julienne
2019-10-14  8:29   ` Shawn Guo
2019-09-24 18:12 ` [PATCH 09/11] of: device: remove comment in of_dma_configure() Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 10/11] of: device: introduce of_dma_configure_parent() Nicolas Saenz Julienne
2019-09-24 18:12 ` [PATCH 11/11] of: simplify of_dma_config()'s arguments Nicolas Saenz Julienne
2019-09-24 21:59 ` Rob Herring [this message]
2019-09-25 14:52   ` [PATCH 00/11] of: Fix DMA configuration for non-DT masters Nicolas Saenz Julienne
2019-09-25 15:09     ` Robin Murphy
2019-09-25 15:30       ` Nicolas Saenz Julienne
2019-09-25 16:16         ` Rob Herring
2019-09-25 16:52           ` Robin Murphy
2019-09-25 21:33             ` Rob Herring
2019-09-26 10:44               ` Nicolas Saenz Julienne
2019-09-26 11:20                 ` Robin Murphy
2019-10-02 18:28                   ` Florian Fainelli
2019-09-25 16:07     ` Rob Herring

Reply instructions:

You may reply publically 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=CAL_Jsq+v+svTyna7UzQdRVqfNc5Z_bgWzxNRXv7-Wqv3NwDu2g@mail.gmail.com \
    --to=robh+dt@kernel.org \
    --cc=dan.j.williams@intel.com \
    --cc=devicetree@vger.kernel.org \
    --cc=dmaengine@vger.kernel.org \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=etnaviv@lists.freedesktop.org \
    --cc=f.fainelli@gmail.com \
    --cc=freedreno@lists.freedesktop.org \
    --cc=frowand.list@gmail.com \
    --cc=james.quinlan@broadcom.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linux-tegra@vger.kernel.org \
    --cc=linux-wireless@vger.kernel.org \
    --cc=mbrugger@suse.com \
    --cc=nsaenzjulienne@suse.de \
    --cc=robin.murphy@arm.com \
    --cc=wahrenst@gmx.net \
    --cc=xen-devel@lists.xenproject.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

dmaengine Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/dmaengine/0 dmaengine/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dmaengine dmaengine/ https://lore.kernel.org/dmaengine \
		dmaengine@vger.kernel.org
	public-inbox-index dmaengine

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.dmaengine


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git