[PATCH v4 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.

CAN-FD is enabled for RK3588. The BRS bus-off issue seen in earlier
testing was caused by the transmit delay compensation setting. With
RKCANFD_REG_TRANSMIT_DELAY_COMPENSATION programmed to 0 on RK3588,
CAN-FD with BRS works in local testing.

Tested on an embedfire,rk3588-lubancat-5io board with can0/can1
directly connected, no other device on the bus, 60 Ohm bus
termination, and a 300 MHz CAN clock. The test used 500 kbit/s
arbitration bitrate and 1, 3 and 5 Mbit/s data bitrates. The 5 Mbit/s
data phase test ran for 15 minutes with:

  ip link set can0 type can bitrate 500000 sample-point 0.8 dbitrate 5000000 dsample-point 0.8 fd on berr-reporting on
  ip link set can1 type can bitrate 500000 sample-point 0.8 dbitrate 5000000 dsample-point 0.8 fd on berr-reporting on
  cangen can0 -I 2 -Li -Di -p 10 -f -g 1 -c32 -b
  cansequence -rv can1 -f

The receiver reported continuous sequence wrap-around messages up to
sequence wrap around (37219). Both interfaces reported 9528377 packets
and 150667356 bytes, with 0 bus-errors, 0 error-warn, 0 error-pass and
0 bus-off events.

Signed-off-by: Cunhao Lu <1579567540 at qq.com>
---
v3 -> v4:
- disable TDC on RK3588 by programming
  RKCANFD_REG_TRANSMIT_DELAY_COMPENSATION to 0
- drop RKCANFD_QUIRK_CANFD_BROKEN for RK3588 and enable CAN-FD support
- document successful RK3588 CAN-FD/BRS testing at 500 kbit/s
  arbitration bitrate and 1, 3 and 5 Mbit/s data bitrates
- collect Krzysztof's Acked-by tag for the binding patch
- Link to v3: https://patch.msgid.link/20260703-master-v3-0-6d56de6fd2f3@qq.com
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

---
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     | 17 ++++++++++
 drivers/net/can/rockchip/rockchip_canfd-rx.c       |  5 ++-
 drivers/net/can/rockchip/rockchip_canfd.h          | 14 +++++++-
 6 files changed, 82 insertions(+), 3 deletions(-)
---
base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482
change-id: 20260702-master-8c52be892a3f

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