[PATCH v3 0/5] dmaengine: Add Peripheral DMA support for SpacemiT K3 SoC

[Troy Mitchell <troy.mitchell@linux.spacemit.com>]

Hi all,

This patch series introduces Peripheral DMA (PDMA) support for the
SpacemiT K3 SoC, leveraging the existing mmp_pdma driver.

The K3 PDMA IP is largely based on the design found in the previous
SpacemiT K1 SoC, but introduces a few key architectural differences:
1. It features a variable extended DRCMR base address for DMA request
   numbers (>= 64) depending on the hardware implementation.
2. Unlike the K1 SoC, where some DMA masters had memory addressing
   limitations (requiring a dedicated dma-bus), the K3 DMA masters
   have full memory addressing capabilities.

The series is structured as follows:
- Patch 1: Introduce the necessary dt-bindings: K3 compatible string.
- Patch 2-3: Refactor the mmp_pdma driver to support variable extended
  DRCMR bases, and add the specific implementation/ops for the K3 SoC.
- Patch 4: Fixes a critical clock issue where the DDR bus clock
  (top_dclk) could be gated by CCF, which would cause DMA engines to
  hang and lead to system instability.
- Patch 5: Finally, instantiates the PDMA controller node in the
  SpacemiT K3 device tree.

---
Changes in v4:
- patch 4/5:
  - add Brian's RB tag
- patch 1/5:
  - update commit message
Link to v3: https://lore.kernel.org/all/20260331-k3-pdma-v3-0-a4e60dd8b4b3@linux.spacemit.com/

Changes in v3:
- Removed the dt-bindings patches related to the DMA number.
- patch 1/5:
  - update commit message
- patch 2-5: nothing
- Link to v2: https://lore.kernel.org/r/20260326-k3-pdma-v2-0-ca94ca7bb595@linux.spacemit.com

Changes in v2:
- patch 1-6 are added in this version
- patch 7/7
  - update commit message
  - using k3 compatible string
  - Link to v1: https://lore.kernel.org/all/20260317-k3-pdma-v1-1-f39d3e97b53a@linux.spacemit.com/

---
Guodong Xu (3):
      dt-bindings: dmaengine: Add SpacemiT K3 DMA compatible string
      dmaengine: mmp_pdma: support variable extended DRCMR base
      dmaengine: mmp_pdma: add Spacemit K3 support

Troy Mitchell (2):
      clk: spacemit: k3: mark top_dclk as CLK_IS_CRITICAL
      riscv: dts: spacemit: Add PDMA controller node for K3 SoC

 .../devicetree/bindings/dma/spacemit,k1-pdma.yaml  |  4 ++-
 arch/riscv/boot/dts/spacemit/k3.dtsi               | 11 +++++++
 drivers/clk/spacemit/ccu-k3.c                      |  2 +-
 drivers/dma/mmp_pdma.c                             | 37 ++++++++++++++++++++--
 4 files changed, 49 insertions(+), 5 deletions(-)
---
base-commit: 02f90981a67f3b9ee7d6684e7503a4fed7aade0c
change-id: 20260317-k3-pdma-7c1734431436

Best regards,
--  
Troy Mitchell <troy.mitchell@linux.spacemit.com>