[PATCH v3 0/4] can: rockchip: add RK3588 CAN support

[Cunhao Lu]

Add support for the RK3588 CAN controller.

RK3588 integrates three CAN-FD controllers that are closely related to
the existing Rockchip CAN-FD IP already supported in the kernel. The
RK3588 variant is not fully compatible with RK3568v2 because the RX
FIFO count register field has a different layout.

This series therefore:

- extends the existing Rockchip CAN-FD binding with the
  rockchip,rk3588-canfd compatible
- adds a dedicated RK3588 match entry and devtype in the driver
- describes the three CAN controller nodes in rk3588-base.dtsi
- enables CAN on the RK3588 Tiger Haikou board

RK3588 encodes RX_FIFO_CNT in bits 7:5 instead of 6:4. This
difference was found by comparing Rockchip's vendor kernel 6.1 CAN
support for RK3568 and RK3588, and was also confirmed by runtime
testing.

RK3588 uses the existing erratum 5 empty-FIFO workaround. Based on
Heiko's testing, v2 also enables the erratum 6 workaround for extended
frames being transmitted as standard frames.

RKCANFD_QUIRK_CANFD_BROKEN remains enabled for RK3588, so CAN-FD stays
disabled for now. Local testing did not reproduce the two known CAN-FD
trigger frames that cause Error Interrupts on RK3568 variants. Instead,
RK3588 shows a different CAN-FD failure mode: CAN-FD frames without BRS
work in this setup, but BRS with a data bitrate different from the
nominal bitrate immediately drives the controller bus-off.

Tested on an embedfire,rk3588-lubancat-5io board with can0/can1
directly connected. Runtime testing used a 200 MHz CAN clock, nominal
bitrate 500 kbit/s, data bitrate 500 kbit/s and 1 Mbit/s, and included
stress and error-path coverage for the existing Rockchip errata handling.

v2 -> v3:
- Move the Changelog below ---
- Collect Heiko's Reviewed-by and the driver patch Tested-by tag
- Use Co-developed-by for Heiko's RK3588 contributions and add his
  Signed-off-by
v1 -> v2:
- use real author name
- fold the single-compatible entries into an enum, as suggested by Krzysztof
- enable the erratum 6 workaround for RK3588 based on Heiko's testing
- add Heiko's RK3588 Tiger Haikou CAN enablement patch
- keep RKCANFD_QUIRK_CANFD_BROKEN enabled for RK3588 so CAN-FD stays disabled
- document the RK3588 CAN-FD/BRS bus-off failure mode

Signed-off-by: Cunhao Lu <1579567540 at qq.com>
---
Cunhao Lu (3):
      dt-bindings: can: rockchip: add rk3588 CAN-FD compatible
      can: rockchip: add RK3588 CAN support
      arm64: dts: rockchip: add CAN-FD nodes for RK3588

Heiko Stuebner (1):
      arm64: dts: rockchip: Enable CAN controller on RK3588-Tiger-Haikou

 .../bindings/net/can/rockchip,rk3568v2-canfd.yaml  |  4 ++-
 arch/arm64/boot/dts/rockchip/rk3588-base.dtsi      | 39 ++++++++++++++++++++++
 .../boot/dts/rockchip/rk3588-tiger-haikou.dts      |  6 ++++
 drivers/net/can/rockchip/rockchip_canfd-core.c     | 12 +++++++
 drivers/net/can/rockchip/rockchip_canfd-rx.c       |  5 ++-
 drivers/net/can/rockchip/rockchip_canfd.h          | 26 ++++++++++++++-
 6 files changed, 89 insertions(+), 3 deletions(-)
---
base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482
change-id: 20260702-master-8c52be892a3f

Best regards,
--  
Cunhao Lu <1579567540 at qq.com>