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

From: Zong Li
Date: Fri Apr 01 2022 - 01:51:18 EST


On Fri, Apr 1, 2022 at 6:42 AM Palmer Dabbelt <palmer@xxxxxxxxxxx> 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@xxxxxxxxxx wrote:
> >> On 30-03-22, 20:15, Palmer Dabbelt wrote:
> >>> On Mon, 28 Mar 2022 02:52:21 PDT (-0700), zong.li@xxxxxxxxxx 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@xxxxxxxxx>
> >>> >
> >>> > 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!