[PATCH v6 0/4] can: rockchip: add RK3588 CAN support

[PATCH v6 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, this series 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@qq.com>
---
v5 -> v6:
- Move the CAN0 assigned clock properties from the Haikou carrier board
  DTS to the Tiger SoM DTSI, as suggested by Quentin.
- Collect Quentin's Tested-by tag for the RK3588 CAN controller nodes.
- Link to v5: https://lore.kernel.org/lkml/tencent_AE0DC47B3FBB26371A1699AC849811AD8007@qq.com
v4 -> v5:
- collect Quentin's Reviewed-by tag for the RK3588 CAN controller nodes
- Link to v4: https://lore.kernel.org/lkml/tencent_42B49B0E68A8659A13EC46A402E41133FC09@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://lore.kernel.org/lkml/tencent_AA108D2806AC225EF9553469D218C8C0260A@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
- Link to v2: https://lore.kernel.org/lkml/tencent_87CB2824608F3C06B4229EF99D3609D00C0A@qq.com
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
- Link to v1: https://lore.kernel.org/lkml/tencent_1A4614039A100DFD8A9AE2692865FE126009@qq.com

To: Marc Kleine-Budde <mkl@pengutronix.de>
To: kernel@pengutronix.de
To: Vincent Mailhol <mailhol@kernel.org>
To: Rob Herring <robh@kernel.org>
To: Krzysztof Kozlowski <krzk+dt@kernel.org>
To: Conor Dooley <conor+dt@kernel.org>
To: Heiko Stuebner <heiko@sntech.de>
Cc: linux-can@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-kernel@vger.kernel.org

---
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      |  4 +++
 arch/arm64/boot/dts/rockchip/rk3588-tiger.dtsi     |  5 +++
 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 +++++++-
 7 files changed, 85 insertions(+), 3 deletions(-)
---
base-commit: 0ce37745d4bfbc493f718169c3974898ffec8ee7
change-id: 20260702-master-8c52be892a3f

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

[PATCH v6 1/4] dt-bindings: can: rockchip: add rk3588 CAN-FD compatible

[Cunhao Lu]

RK3588 integrates a Rockchip CAN-FD controller variant that is not
fully compatible with RK3568v2. The RX FIFO count register field is
encoded in bits 7:5 on RK3588, while RK3568v2 uses bits 6:4.

Add a dedicated rockchip,rk3588-canfd compatible to describe this
variant. Do not use rockchip,rk3568v2-canfd as a fallback, because that
would describe a register layout that does not match the hardware.

Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Cunhao Lu <1579567540@qq.com>
---
v3 -> v4:
- Collect Krzysztof's Acked-by tag.
v2 -> v3:
- Move the Changelog below ---
- Collect Heiko's Reviewed-by tag
v1 -> v2:
- Use enum for the single-compatible entries, as suggested by Krzysztof.
- Reword the commit message to explain the hardware difference instead
  of referring to Linux driver match data.
---
 .../devicetree/bindings/net/can/rockchip,rk3568v2-canfd.yaml          | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/net/can/rockchip,rk3568v2-canfd.yaml b/Documentation/devicetree/bindings/net/can/rockchip,rk3568v2-canfd.yaml
index a077c0330013..81e2b6dfeb02 100644
--- a/Documentation/devicetree/bindings/net/can/rockchip,rk3568v2-canfd.yaml
+++ b/Documentation/devicetree/bindings/net/can/rockchip,rk3568v2-canfd.yaml
@@ -16,7 +16,9 @@ allOf:
 properties:
   compatible:
     oneOf:
-      - const: rockchip,rk3568v2-canfd
+      - enum:
+          - rockchip,rk3568v2-canfd
+          - rockchip,rk3588-canfd
       - items:
           - const: rockchip,rk3568v3-canfd
           - const: rockchip,rk3568v2-canfd

-- 
2.34.1

[PATCH v6 2/4] can: rockchip: add RK3588 CAN support

[Cunhao Lu]

Add support for the RK3588 CAN controller by introducing a dedicated
model ID and OF match entry.

The block is closely related to the existing RK3568 variants, but it
cannot reuse their match data unchanged. In particular, RK3588
encodes RX_FIFO_CNT in bits 7:5 instead of 6:4, so the RX path needs
SoC-specific handling.

The RX FIFO count bitfield difference was found by comparing Rockchip's
vendor kernel 6.1 CAN support for RK3568 and RK3588. Runtime testing on
RK3588 also confirms that bits 7:5 are needed.

Enable the existing erratum 5 empty-FIFO workaround for RK3588.
Heiko reproduced erratum 6 on RK3588, so enable that workaround as
well.

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. Runtime testing 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 cangen using BRS and
cansequence on the receiver. Both interfaces reported 9528377 packets
and 150667356 bytes, with 0 bus-errors, 0 error-warn, 0 error-pass and
0 bus-off events.

Co-developed-by: Heiko Stuebner <heiko.stuebner@cherry.de>
Signed-off-by: Heiko Stuebner <heiko.stuebner@cherry.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Cunhao Lu <1579567540@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.
v2 -> v3:
- Use Co-developed-by for Heiko's RK3588 contributions and add his
  Signed-off-by
- Collect Heiko's Reviewed-by and Tested-by tags
---
 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 +++++++++++++-
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/rockchip/rockchip_canfd-core.c b/drivers/net/can/rockchip/rockchip_canfd-core.c
index 29de0c01e4ed..37c1c22c40c9 100644
--- a/drivers/net/can/rockchip/rockchip_canfd-core.c
+++ b/drivers/net/can/rockchip/rockchip_canfd-core.c
@@ -50,6 +50,12 @@ static const struct rkcanfd_devtype_data rkcanfd_devtype_data_rk3568v3 = {
 		RKCANFD_QUIRK_CANFD_BROKEN,
 };
 
+static const struct rkcanfd_devtype_data rkcanfd_devtype_data_rk3588 = {
+	.model = RKCANFD_MODEL_RK3588,
+	.quirks = RKCANFD_QUIRK_RK3568_ERRATUM_5 |
+		RKCANFD_QUIRK_RK3568_ERRATUM_6,
+};
+
 static const char *__rkcanfd_get_model_str(enum rkcanfd_model model)
 {
 	switch (model) {
@@ -57,6 +63,8 @@ static const char *__rkcanfd_get_model_str(enum rkcanfd_model model)
 		return "rk3568v2";
 	case RKCANFD_MODEL_RK3568V3:
 		return "rk3568v3";
+	case RKCANFD_MODEL_RK3588:
+		return "rk3588";
 	}
 
 	return "<unknown>";
@@ -148,6 +156,12 @@ static int rkcanfd_set_bittiming(struct rkcanfd_priv *priv)
 
 	rkcanfd_write(priv, RKCANFD_REG_FD_DATA_BITTIMING, reg_dbt);
 
+	/* RK3588 CAN-FD BRS works with TDC disabled. */
+	if (priv->devtype_data.model == RKCANFD_MODEL_RK3588) {
+		rkcanfd_write(priv, RKCANFD_REG_TRANSMIT_DELAY_COMPENSATION, 0);
+		return 0;
+	}
+
 	tdco = (priv->can.clock.freq / dbt->bitrate) * 2 / 3;
 	tdco = min(tdco, FIELD_MAX(RKCANFD_REG_TRANSMIT_DELAY_COMPENSATION_TDC_OFFSET));
 
@@ -846,6 +860,9 @@ static const struct of_device_id rkcanfd_of_match[] = {
 	}, {
 		.compatible = "rockchip,rk3568v3-canfd",
 		.data = &rkcanfd_devtype_data_rk3568v3,
+	}, {
+		.compatible = "rockchip,rk3588-canfd",
+		.data = &rkcanfd_devtype_data_rk3588,
 	}, {
 		/* sentinel */
 	},
diff --git a/drivers/net/can/rockchip/rockchip_canfd-rx.c b/drivers/net/can/rockchip/rockchip_canfd-rx.c
index 475c0409e215..24e87daa1df0 100644
--- a/drivers/net/can/rockchip/rockchip_canfd-rx.c
+++ b/drivers/net/can/rockchip/rockchip_canfd-rx.c
@@ -281,7 +281,10 @@ rkcanfd_rx_fifo_get_len(const struct rkcanfd_priv *priv)
 {
 	const u32 reg = rkcanfd_read(priv, RKCANFD_REG_RX_FIFO_CTRL);
 
-	return FIELD_GET(RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_CNT, reg);
+	if (priv->devtype_data.model == RKCANFD_MODEL_RK3588)
+		return FIELD_GET(RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_CNT_RK3588, reg);
+
+	return FIELD_GET(RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_CNT_RK3568, reg);
 }
 
 int rkcanfd_handle_rx_int(struct rkcanfd_priv *priv)
diff --git a/drivers/net/can/rockchip/rockchip_canfd.h b/drivers/net/can/rockchip/rockchip_canfd.h
index 93131c7d7f54..95bea9bfd8a2 100644
--- a/drivers/net/can/rockchip/rockchip_canfd.h
+++ b/drivers/net/can/rockchip/rockchip_canfd.h
@@ -214,7 +214,8 @@
 #define RKCANFD_REG_TXEVENT_FIFO_CTRL_TXE_FIFO_ENABLE BIT(0)
 
 #define RKCANFD_REG_RX_FIFO_CTRL 0x118
-#define RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_CNT GENMASK(6, 4)
+#define RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_CNT_RK3568 GENMASK(6, 4)
+#define RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_CNT_RK3588 GENMASK(7, 5)
 #define RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_FULL_WATERMARK GENMASK(3, 1)
 #define RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_ENABLE BIT(0)
 
@@ -331,6 +332,11 @@
  * rarely with the standard clock of 300 MHz, but almost immediately
  * at 80 MHz.
  *
+ * Tests on the rk3588 show the same empty FIFO condition.
+ * In that setup rx_fifo_empty_errors increments when the bus
+ * transitions from idle to high CAN-FD load and stops growing once
+ * the bus reaches a steady state.
+ *
  * To workaround this problem, check for empty FIFO with
  * rkcanfd_fifo_header_empty() in rkcanfd_handle_rx_int_one() and exit
  * early.
@@ -344,6 +350,8 @@
 /* Erratum 6: The CAN controller's transmission of extended frames may
  * intermittently change into standard frames
  *
+ * Tests on the rk3588 show the same problem.
+ *
  * Work around this issue by activating self reception (RXSTX). If we
  * have pending TX CAN frames, check all RX'ed CAN frames in
  * rkcanfd_rxstx_filter().
@@ -424,6 +432,9 @@
  *     cansequence -rv -i 1
  *
  * - TX starvation after repeated Bus-Off
+ *   Tests on the rk3588 show the same problem. In a
+ *   10-cycle Bus-Off recovery test, 9 cycles failed to send after the
+ *   controller restarted.
  *   To reproduce:
  *   host:
  *     sleep 3 && cangen can0 -I2 -Li -Di -p10 -g 0.0
@@ -434,6 +445,7 @@
 enum rkcanfd_model {
 	RKCANFD_MODEL_RK3568V2 = 0x35682,
 	RKCANFD_MODEL_RK3568V3 = 0x35683,
+	RKCANFD_MODEL_RK3588 = 0x3588,
 };
 
 struct rkcanfd_devtype_data {

-- 
2.34.1

[PATCH v6 3/4] arm64: dts: rockchip: add CAN-FD nodes for RK3588

[Cunhao Lu]

Describe the three CAN-FD controllers integrated in RK3588 in the base
SoC .dtsi.

Add CAN0, CAN1 and CAN2 nodes with their register ranges, interrupts,
clocks and resets, and keep them disabled by default so board DTS files
can enable them as needed.

Co-developed-by: Heiko Stuebner <heiko.stuebner@cherry.de>
Signed-off-by: Heiko Stuebner <heiko.stuebner@cherry.de>
Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Tested-by: Quentin Schulz <quentin.schulz@cherry.de> # RK3588 Jaguar
Signed-off-by: Cunhao Lu <1579567540@qq.com>
---
v5 -> v6:
- Collect Quentin's Tested-by tag
v4 -> v5:
- Collect Quentin's Reviewed-by tag
v2 -> v3:
- Use Co-developed-by for Heiko's RK3588 contributions and add his
  Signed-off-by
---
 arch/arm64/boot/dts/rockchip/rk3588-base.dtsi | 39 +++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi b/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi
index fc1fdbfd3162..b340973775c5 100644
--- a/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi
@@ -2648,6 +2648,45 @@ dmac1: dma-controller@fea30000 {
 		#dma-cells = <1>;
 	};
 
+	can0: can@fea50000 {
+		compatible = "rockchip,rk3588-canfd";
+		reg = <0x0 0xfea50000 0x0 0x1000>;
+		interrupts = <GIC_SPI 341 IRQ_TYPE_LEVEL_HIGH 0>;
+		clocks = <&cru CLK_CAN0>, <&cru PCLK_CAN0>;
+		clock-names = "baud", "pclk";
+		resets = <&cru SRST_CAN0>, <&cru SRST_P_CAN0>;
+		reset-names = "core", "apb";
+		pinctrl-names = "default";
+		pinctrl-0 = <&can0m0_pins>;
+		status = "disabled";
+	};
+
+	can1: can@fea60000 {
+		compatible = "rockchip,rk3588-canfd";
+		reg = <0x0 0xfea60000 0x0 0x1000>;
+		interrupts = <GIC_SPI 342 IRQ_TYPE_LEVEL_HIGH 0>;
+		clocks = <&cru CLK_CAN1>, <&cru PCLK_CAN1>;
+		clock-names = "baud", "pclk";
+		resets = <&cru SRST_CAN1>, <&cru SRST_P_CAN1>;
+		reset-names = "core", "apb";
+		pinctrl-names = "default";
+		pinctrl-0 = <&can1m0_pins>;
+		status = "disabled";
+	};
+
+	can2: can@fea70000 {
+		compatible = "rockchip,rk3588-canfd";
+		reg = <0x0 0xfea70000 0x0 0x1000>;
+		interrupts = <GIC_SPI 343 IRQ_TYPE_LEVEL_HIGH 0>;
+		clocks = <&cru CLK_CAN2>, <&cru PCLK_CAN2>;
+		clock-names = "baud", "pclk";
+		resets = <&cru SRST_CAN2>, <&cru SRST_P_CAN2>;
+		reset-names = "core", "apb";
+		pinctrl-names = "default";
+		pinctrl-0 = <&can2m0_pins>;
+		status = "disabled";
+	};
+
 	i2c1: i2c@fea90000 {
 		compatible = "rockchip,rk3588-i2c", "rockchip,rk3399-i2c";
 		reg = <0x0 0xfea90000 0x0 0x1000>;

-- 
2.34.1

[PATCH v6 4/4] arm64: dts: rockchip: Enable CAN controller on RK3588-Tiger-Haikou

[Cunhao Lu]

From: Heiko Stuebner <heiko.stuebner@cherry.de>

CAN0 is piped through the Q7 connector to the CAN header on the Haikou
baseboard, so enable support for it there.

At least on RK3588 Tiger, the CAN clocks default to 99 MHz, limiting
usable CAN bitrates without skew. The RK3568 errata documentation
mentions 300 MHz as the default frequency, so request the same rate to
allow more bitrates.

The CAN clock setup is common to the Tiger SoM regardless of which
carrier board exposes CAN0, so place it in rk3588-tiger.dtsi. Keep CAN0
disabled by default and enable it in rk3588-tiger-haikou.dts, where the
carrier board routes it to a transceiver.

Signed-off-by: Heiko Stuebner <heiko.stuebner@cherry.de>
Signed-off-by: Cunhao Lu <1579567540@qq.com>
---
 arch/arm64/boot/dts/rockchip/rk3588-tiger-haikou.dts | 4 ++++
 arch/arm64/boot/dts/rockchip/rk3588-tiger.dtsi       | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3588-tiger-haikou.dts b/arch/arm64/boot/dts/rockchip/rk3588-tiger-haikou.dts
index 873fbeb8daa1..6c57c9f54a30 100644
--- a/arch/arm64/boot/dts/rockchip/rk3588-tiger-haikou.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3588-tiger-haikou.dts
@@ -155,6 +155,10 @@ vddd_audio_1v6: regulator-vddd-audio-1v6 {
 	};
 };
 
+&can0 {
+	status = "okay";
+};
+
 &combphy2_psu {
 	status = "okay";
 };
diff --git a/arch/arm64/boot/dts/rockchip/rk3588-tiger.dtsi b/arch/arm64/boot/dts/rockchip/rk3588-tiger.dtsi
index 139f70e7bbd9..161c89c62bcd 100644
--- a/arch/arm64/boot/dts/rockchip/rk3588-tiger.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3588-tiger.dtsi
@@ -90,6 +90,11 @@ vcc5v0_sys: regulator-vcc5v0-sys {
 	};
 };
 
+&can0 {
+	assigned-clocks = <&cru CLK_CAN0>;
+	assigned-clock-rates = <300000000>;
+};
+
 &cpu_b0 {
 	cpu-supply = <&vdd_cpu_big0_s0>;
 };

-- 
2.34.1

Re: [PATCH v6 4/4] arm64: dts: rockchip: Enable CAN controller on RK3588-Tiger-Haikou

[Quentin Schulz]

Hi Cunhao,

On 7/30/26 4:34 PM, Cunhao Lu wrote:
> From: Heiko Stuebner <heiko.stuebner@cherry.de>
> 
> CAN0 is piped through the Q7 connector to the CAN header on the Haikou
> baseboard, so enable support for it there.
> 
> At least on RK3588 Tiger, the CAN clocks default to 99 MHz, limiting
> usable CAN bitrates without skew. The RK3568 errata documentation
> mentions 300 MHz as the default frequency, so request the same rate to
> allow more bitrates.
> 
> The CAN clock setup is common to the Tiger SoM regardless of which
> carrier board exposes CAN0, so place it in rk3588-tiger.dtsi. Keep CAN0
> disabled by default and enable it in rk3588-tiger-haikou.dts, where the
> carrier board routes it to a transceiver.
> 

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>

Thanks!
Quentin

Re: [PATCH v6 2/4] can: rockchip: add RK3588 CAN support

[Marc Kleine-Budde]

[-- Attachment #1: Type: text/plain, Size: 4396 bytes --]

On 30.07.2026 22:34:03, Cunhao Lu wrote:
> Add support for the RK3588 CAN controller by introducing a dedicated
> model ID and OF match entry.
>
> The block is closely related to the existing RK3568 variants, but it
> cannot reuse their match data unchanged. In particular, RK3588
> encodes RX_FIFO_CNT in bits 7:5 instead of 6:4, so the RX path needs
> SoC-specific handling.
>
> The RX FIFO count bitfield difference was found by comparing Rockchip's
> vendor kernel 6.1 CAN support for RK3568 and RK3588. Runtime testing on
> RK3588 also confirms that bits 7:5 are needed.
>
> Enable the existing erratum 5 empty-FIFO workaround for RK3588.
> Heiko reproduced erratum 6 on RK3588, so enable that workaround as
> well.
>
> 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. Runtime testing 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 cangen using BRS and
> cansequence on the receiver. Both interfaces reported 9528377 packets
> and 150667356 bytes, with 0 bus-errors, 0 error-warn, 0 error-pass and
> 0 bus-off events.
>
> Co-developed-by: Heiko Stuebner <heiko.stuebner@cherry.de>
> Signed-off-by: Heiko Stuebner <heiko.stuebner@cherry.de>
> Tested-by: Heiko Stuebner <heiko@sntech.de>
> Reviewed-by: Heiko Stuebner <heiko@sntech.de>
> Signed-off-by: Cunhao Lu <1579567540@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.
> v2 -> v3:
> - Use Co-developed-by for Heiko's RK3588 contributions and add his
>   Signed-off-by
> - Collect Heiko's Reviewed-by and Tested-by tags
> ---
>  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 +++++++++++++-
>  3 files changed, 34 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/can/rockchip/rockchip_canfd-core.c b/drivers/net/can/rockchip/rockchip_canfd-core.c
> index 29de0c01e4ed..37c1c22c40c9 100644
> --- a/drivers/net/can/rockchip/rockchip_canfd-core.c
> +++ b/drivers/net/can/rockchip/rockchip_canfd-core.c
> @@ -50,6 +50,12 @@ static const struct rkcanfd_devtype_data rkcanfd_devtype_data_rk3568v3 = {
>  		RKCANFD_QUIRK_CANFD_BROKEN,
>  };
>
> +static const struct rkcanfd_devtype_data rkcanfd_devtype_data_rk3588 = {
> +	.model = RKCANFD_MODEL_RK3588,
> +	.quirks = RKCANFD_QUIRK_RK3568_ERRATUM_5 |
> +		RKCANFD_QUIRK_RK3568_ERRATUM_6,
> +};
> +
>  static const char *__rkcanfd_get_model_str(enum rkcanfd_model model)
>  {
>  	switch (model) {
> @@ -57,6 +63,8 @@ static const char *__rkcanfd_get_model_str(enum rkcanfd_model model)
>  		return "rk3568v2";
>  	case RKCANFD_MODEL_RK3568V3:
>  		return "rk3568v3";
> +	case RKCANFD_MODEL_RK3588:
> +		return "rk3588";
>  	}
>
>  	return "<unknown>";
> @@ -148,6 +156,12 @@ static int rkcanfd_set_bittiming(struct rkcanfd_priv *priv)
>
>  	rkcanfd_write(priv, RKCANFD_REG_FD_DATA_BITTIMING, reg_dbt);
>
> +	/* RK3588 CAN-FD BRS works with TDC disabled. */
> +	if (priv->devtype_data.model == RKCANFD_MODEL_RK3588) {
> +		rkcanfd_write(priv, RKCANFD_REG_TRANSMIT_DELAY_COMPENSATION, 0);
> +		return 0;
> +	}
> +

Can you attach the TDC to the CAN framework? See commit 5e1663810e11
("can: mcp251xfd: fix TDC setting for low data bit rates"). And check if
CAN-FD works on the rk3588 works?

Marc

>  	tdco = (priv->can.clock.freq / dbt->bitrate) * 2 / 3;
>  	tdco = min(tdco, FIELD_MAX(RKCANFD_REG_TRANSMIT_DELAY_COMPENSATION_TDC_OFFSET));

--
Pengutronix e.K.                 | Marc Kleine-Budde          |
Embedded Linux                   | https://www.pengutronix.de |
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Re: [PATCH v6 2/4] can: rockchip: add RK3588 CAN support

[Cunhao Lu]

Hi Marc,

> Can you attach the TDC to the CAN framework? See commit 5e1663810e11
> ("can: mcp251xfd: fix TDC setting for low data bit rates"). And check if
> CAN-FD works on the rk3588 works?

Could we leave the RK3588 TDC support out of this patch series for now?

I will test whether CAN-FD works on RK3588 with TDC integrated with the
CAN framework and report the test result. If the testing shows that it
works, I will enable it in a separate follow-up patch.

Thanks,
Cunhao

Re: [PATCH v6 2/4] can: rockchip: add RK3588 CAN support

[Marc Kleine-Budde]

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On 31.07.2026 17:23:45, Cunhao Lu wrote:
> Hi Marc,
>
> > Can you attach the TDC to the CAN framework? See commit 5e1663810e11
> > ("can: mcp251xfd: fix TDC setting for low data bit rates"). And check if
> > CAN-FD works on the rk3588 works?
>
> Could we leave the RK3588 TDC support out of this patch series for now?

..and mark the rk3588 as RKCANFD_QUIRK_CANFD_BROKEN for now? Fine with me.

> I will test whether CAN-FD works on RK3588 with TDC integrated with the
> CAN framework and report the test result. If the testing shows that it
> works, I will enable it in a separate follow-up patch.

Sounds good,
Marc

-- 
Pengutronix e.K.                 | Marc Kleine-Budde          |
Embedded Linux                   | https://www.pengutronix.de |
Vertretung Nürnberg              | Phone: +49-5121-206917-129 |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-9   |

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Re: [PATCH v6 2/4] can: rockchip: add RK3588 CAN support

[Cunhao Lu]

Hi Marc,

> > > Can you attach the TDC to the CAN framework? See commit 5e1663810e11
> > > ("can: mcp251xfd: fix TDC setting for low data bit rates"). And check if
> > > CAN-FD works on the rk3588 works?
> >
> > Could we leave the RK3588 TDC support out of this patch series for now?
> 
> ..and mark the rk3588 as RKCANFD_QUIRK_CANFD_BROKEN for now? Fine with me.

I have finished testing the CAN-FD TDC integration on RK3588.

Enabling TDC makes the transmitter enter bus-off for every TDCO value
tested. This includes the framework value (TDCO=48), TDCO=0, and the
non-zero values 1, 8, 16, 24, 32, 40, 48 and 56. With TDCO=63, only one
frame was received during a 10 second test, so that setting is not usable.

I checked the register definition against Rockchip RK3588 TRM
V1.0-Part1-20220309.pdf. The driver uses CAN_TRANSMIT_DELAY_COMPENSATION at
offset 0x108, with tdc_offset in bits 6:1 and tdc_enable in bit 0, which
matches the TRM. Thus, the failure is not explained by an incorrect register
address or field definition.

The test setup was:

  Board:             embedfire,rk3588-lubancat-5io
  CAN clock:         300 MHz
  Nominal bitrate:   500 kbit/s
  Data bitrate:      5 Mbit/s
  Sample points:     80% nominal, 80% data
  Bus:               can0 and can1 directly connected, 60 Ohm termination

With TDC disabled, about 29,775 frames were received in three seconds with
no bus errors. With TDC enabled, can0 typically reached bus-off after about
15-31 bus errors.

This is a preliminary indication of a problem in the RK3588 CAN IP TDC
path, although it is not sufficient to prove a silicon defect. In
particular, the hardware-measured transmitter delay (TDCV) is not observable
through the registers described by the TRM, so the TDC offset semantics
still need to be verified independently.

TDC is not a mandatory feature for a CAN-FD implementation. It compensates
the TX-to-RX loop delay when that delay would otherwise consume the timing
margin before the normal sample point. Whether it must be enabled depends on
the complete hardware path, including the controller, transceiver, PCB and
bus. It is therefore not required solely because CAN-FD or a particular
data bitrate is used.

On the board used for this test, CAN-FD runs reliably at 5 Mbit/s with TDC
disabled and no lost frames. This demonstrates that RK3588 supports CAN-FD,
while the maximum usable data bitrate still depends on the board design and
its TX-to-RX delay. Boards with a longer delay may need a lower data bitrate,
just as different CAN transceivers have different maximum data-rate
specifications (for example, 8 Mbit/s for some devices and 5 Mbit/s for
others).

In my opinion, enabling CAN-FD support on RK3588 is independent of TDC.
TDC is an optimization for hardware paths that need additional TX-to-RX
delay compensation, rather than a prerequisite for CAN-FD operation. I would
therefore still like to enable CAN-FD support for RK3588 in this series while
keeping TDC disabled. TDC support can be investigated separately in a
follow-up patch once its behavior has been understood.

Best regards,
Cunhao