Re: [PATCH v8 0/4] Determine the number of DMA channels by 'dma-channels' property

From: Zong Li <zong.li@sifive.com>
To: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Vinod <vkoul@kernel.org>, Rob Herring <robh+dt@kernel.org>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
	Conor Dooley <conor.dooley@microchip.com>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Bin Meng <bin.meng@windriver.com>,
	Green Wan <green.wan@sifive.com>,
	dmaengine <dmaengine@vger.kernel.org>,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
	<devicetree@vger.kernel.org>,
	"linux-kernel@vger.kernel.org List"
	<linux-kernel@vger.kernel.org>,
	linux-riscv <linux-riscv@lists.infradead.org>
Subject: Re: [PATCH v8 0/4] Determine the number of DMA channels by 'dma-channels' property
Date: Fri, 1 Apr 2022 13:50:50 +0800	[thread overview]
Message-ID: <CANXhq0oJKRVV2QyzJ2WV1fjcw3piyoKeiR5U-=DqsyDayixTGA@mail.gmail.com> (raw)
In-Reply-To: <mhng-5afad1be-9b06-4cd1-95e3-c21605b9086a@palmer-mbp2014>

On Fri, Apr 1, 2022 at 6:42 AM Palmer Dabbelt <palmer@dabbelt.com> wrote:
>
> On Wed, 30 Mar 2022 22:54:47 PDT (-0700), Palmer Dabbelt wrote:
> > On Wed, 30 Mar 2022 22:21:56 PDT (-0700), vkoul@kernel.org wrote:
> >> On 30-03-22, 20:15, Palmer Dabbelt wrote:
> >>> On Mon, 28 Mar 2022 02:52:21 PDT (-0700), zong.li@sifive.com wrote:
> >>> > The PDMA driver currently assumes there are four channels by default, it
> >>> > might cause the error if there is actually less than four channels.
> >>> > Change that by getting number of channel dynamically from device tree.
> >>> > For backwards-compatible, it uses the default value (i.e. 4) when there
> >>> > is no 'dma-channels' information in dts.
> >>> >
> >>> > This patch set contains the dts and dt-bindings change.
> >>> >
> >>> > Changed in v8:
> >>> >  - Rebase on master
> >>> >  - Remove modification of microchip-mpfs.dtsi
> >>> >  - Rename DMA node name of fu540-c000.dtsi
> >>> >
> >>> > Changed in v7:
> >>> >  - Rebase on tag v5.17-rc7
> >>> >  - Modify the subject of patch
> >>> >
> >>> > Changed in v6:
> >>> >  - Rebase on tag v5.17-rc6
> >>> >  - Change sf_pdma.chans[] to a flexible array member.
> >>> >
> >>> > Changed in v5:
> >>> >  - Rebase on tag v5.17-rc3
> >>> >  - Fix typo in dt-bindings and commit message
> >>> >  - Add PDMA versioning scheme for compatible
> >>> >
> >>> > Changed in v4:
> >>> >  - Remove cflags of debug use reported-by: kernel test robot <lkp@intel.com>
> >>> >
> >>> > Changed in v3:
> >>> >  - Fix allocating wrong size
> >>> >  - Return error if 'dma-channels' is larger than maximum
> >>> >
> >>> > Changed in v2:
> >>> >  - Rebase on tag v5.16
> >>> >  - Use 4 as default value of dma-channels
> >>> >
> >>> > Zong Li (4):
> >>> >   dt-bindings: dma-engine: sifive,fu540: Add dma-channels property and
> >>> >     modify compatible
> >>> >   riscv: dts: Add dma-channels property and modify compatible
> >>> >   riscv: dts: rename the node name of dma
> >>> >   dmaengine: sf-pdma: Get number of channel by device tree
> >>> >
> >>> >  .../bindings/dma/sifive,fu540-c000-pdma.yaml  | 19 +++++++++++++--
> >>> >  arch/riscv/boot/dts/sifive/fu540-c000.dtsi    |  5 ++--
> >>> >  drivers/dma/sf-pdma/sf-pdma.c                 | 24 ++++++++++++-------
> >>> >  drivers/dma/sf-pdma/sf-pdma.h                 |  8 ++-----
> >>> >  4 files changed, 38 insertions(+), 18 deletions(-)
> >>>
> >>> Thanks, these are on for-next.
> >>
> >> The drivers/dma/ should go thru dmaengine tree. During merge window I
> >> dont apply the patches
> >
> > OK, I can drop this from my tree if you'd like?
>
> Just to follow up from IRC: I'm dropping these from my tree.

Hi Palmer and Vinod,
Many thanks for your help. As all you suggested, let's go this
patchset by the dmaengine tree. Thanks a lot!