Re: [PATCH v3 0/9] STM32 DMA3 updates for STM32MP25

[Alexandre TORGUE <alexandre.torgue@foss.st.com>]

Hi

On 10/16/24 14:39, Amelie Delaunay wrote:
> The HW version of STM32 DMA3 inside STM32MP25 requires some tunings to
> meet the needs of the interconnect. This series adds the linked list
> refactoring feature to have optimal performance when addressing the
> memory, and it adds the use of two new bits in the third cell specifying
> the DMA transfer requirements:
> - bit[16] to prevent packing/unpacking mode to avoid bytes loss in case
> of interrupting an ongoing transfer (e.g. UART RX),
> - bit[17] to prevent linked-list refactoring because some peripherals
> (e.g. FMC ECC) require a one-shot transfer, they trigger the DMA only
> once.
> It also adds platform data to clamp the burst length on AXI port,
> especially when it is interconnected to AXI3 bus, such as on STM32MP25.
> Finally this series also contains STM32MP25 device tree updates, to add
> DMA support on SPI, I2C, UART and apply the tunings introduced.
> 
> Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
> ---
> Changes in v3:
> - Refine commit description of patch 4 about preventing
>    additionnal transfers, as per Rob's suggestion.
> - Link to v2: https://lore.kernel.org/r/20241015-dma3-mp25-updates-v2-0-b63e21556ec8@foss.st.com
> 
> Changes in v2:
> - Reword commit title/message/content of patch 4 about preventing
>    additionnal transfers, as per Rob's suggestion
> - Rework AXI maximum burst length management using SoC specific
>    compatible, as pointed out by Rob
> - Drop former patches 6 and 8, which are no longer relevant
> - Link to v1: https://lore.kernel.org/r/20241010-dma3-mp25-updates-v1-0-adf0633981ea@foss.st.com
> 
> ---
> Amelie Delaunay (9):
>        dt-bindings: dma: stm32-dma3: prevent packing/unpacking mode
>        dmaengine: stm32-dma3: prevent pack/unpack thanks to DT configuration
>        dmaengine: stm32-dma3: refactor HW linked-list to optimize memory accesses
>        dt-bindings: dma: stm32-dma3: prevent additional transfers
>        dmaengine: stm32-dma3: prevent LL refactoring thanks to DT configuration
>        dmaengine: stm32-dma3: clamp AXI burst using match data
>        arm64: dts: st: add DMA support on U(S)ART instances of stm32mp25
>        arm64: dts: st: add DMA support on I2C instances of stm32mp25
>        arm64: dts: st: add DMA support on SPI instances of stm32mp25
> 

Patches [7], [8], and [9] applied on stm32-next.

Thanks
Alex



>   .../bindings/dma/stm32/st,stm32-dma3.yaml          |   6 ++
>   arch/arm64/boot/dts/st/stm32mp251.dtsi             |  75 +++++++++++++
>   arch/arm64/boot/dts/st/stm32mp257f-ev1.dts         |   2 +
>   drivers/dma/stm32/stm32-dma3.c                     | 119 +++++++++++++++++----
>   4 files changed, 182 insertions(+), 20 deletions(-)
> ---
> base-commit: 76355c25e4f71ee4667ebaadd9faf8ec29d18f23
> change-id: 20241015-dma3-mp25-updates-d7f26753b0dd
> 
> Best regards,