Re: [PATCH 0/3] dmaengine: dw-edma: Add support for native HDMA

From: Serge Semin
Date: Thu Feb 09 2023 - 17:41:22 EST


Hello Cai

On Wed, Sep 21, 2022 at 02:48:49PM +0800, Cai Huoqing wrote:
> From: caihuoqing <caihuoqing@xxxxxxxxx>
>
> Add support for HDMA NATIVE, as long the IP design has set
> the compatible register map parameter-HDMA_NATIVE,
> which allows compatibility for native HDMA register configuration.
>
> The HDMA Hyper-DMA IP is an enhancement of the eDMA embedded-DMA IP.
> And the native HDMA registers are different from eDMA,
> so this patch add support for HDMA NATIVE mode.
>
> HDMA write and read channels operate independently to maximize
> the performance of the HDMA read and write data transfer over
> the link When you configure the HDMA with multiple read channels,
> then it uses a round robin (RR) arbitration scheme to select
> the next read channel to be serviced.
> The same applies when you have multiple write channels.
>
> The native HDMA driver also supports a maximum of 16 independent
> channels (8 write + 8 read), which can run simultaneously.
> Both SAR (Source Address Register) and DAR (Destination Address Register)
> are alignmented to byte.dmaengine: dw-edma: Add support for native HDMA
>
> These series based on the series
> https://lore.kernel.org/dmaengine/20220822185332.26149-1-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/

My DW PCIe/eDMA series has been finally accepted by @Bjorn:
https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/log/?h=pci/ctrl/dwc
(@Lorenzo, please note my changes in your pci/dwc are a bit outdated.)
The patchset will get into the mainline kernel on v6.3. So if you want
your series to go further you'll need either rebase your patches on the
@Bjorn's branch or wait for the kernel v6.3 release and rebase your work
on top of the latest kernel then. I'll provide some comments regarding
this patchset shortly.

-Serge(y)

>
> Cai Huoqing (3):
> dmaengine: dw-edma: Rename dw_edma_core_ops structure to
> dw_edma_plat_ops
> dmaengine: dw-edma: Create a new dw_edma_core_ops structure to
> abstract controller operation
> dmaengine: dw-edma: Add support for native HDMA
>
> drivers/dma/dw-edma/Makefile | 6 +-
> drivers/dma/dw-edma/dw-edma-core.c | 65 ++---
> drivers/dma/dw-edma/dw-edma-core.h | 19 ++
> drivers/dma/dw-edma/dw-edma-pcie.c | 4 +-
> drivers/dma/dw-edma/dw-edma-v0-core.c | 90 ++++++-
> drivers/dma/dw-edma/dw-edma-v0-core.h | 14 +-
> drivers/dma/dw-edma/dw-hdma-v0-core.c | 304 +++++++++++++++++++++++
> drivers/dma/dw-edma/dw-hdma-v0-core.h | 17 ++
> drivers/dma/dw-edma/dw-hdma-v0-debugfs.c | 150 +++++++++++
> drivers/dma/dw-edma/dw-hdma-v0-debugfs.h | 22 ++
> drivers/dma/dw-edma/dw-hdma-v0-regs.h | 98 ++++++++
> include/linux/dma/edma.h | 7 +-
> 12 files changed, 725 insertions(+), 71 deletions(-)
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-core.c
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-core.h
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-debugfs.c
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-debugfs.h
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-regs.h
>
> --
> 2.25.1
>