Merge tag 'linux-can-next-for-6.4-20230404-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2023-04-04-2

The first patch is by Oliver Hartkopp and makes the maximum pdu size
of the CAN ISOTP protocol configurable.

The following 5 patches are by Dario Binacchi and add support for the
bxCAN controller by ST.

Geert Uytterhoeven's patch for the rcar_canfd driver fixes a sparse
warning.

Peng Fan's patch adds an optional power-domains property to the
flexcan device tree binding.

Frank Jungclaus adds support for CAN_CTRLMODE_BERR_REPORTING to the
esd_usb driver.

The last patch is by Oliver Hartkopp and converts the USB IDs of the
kvaser_usb driver to hexadecimal values.

* tag 'linux-can-next-for-6.4-20230404-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next:
  kvaser_usb: convert USB IDs to hexadecimal values
  can: esd_usb: Add support for CAN_CTRLMODE_BERR_REPORTING
  dt-bindings: can: fsl,flexcan: add optional power-domains property
  can: rcar_canfd: rcar_canfd_probe(): fix plain integer in transceivers[] init
  can: bxcan: add support for ST bxCAN controller
  ARM: dts: stm32: add pin map for CAN controller on stm32f4
  ARM: dts: stm32: add CAN support on stm32f429
  dt-bindings: net: can: add STM32 bxcan DT bindings
  dt-bindings: arm: stm32: add compatible for syscon gcan node
  can: isotp: add module parameter for maximum pdu size
====================

Link: https://lore.kernel.org/r/20230404145908.1714400-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

13 files changed, 1395 insertions, 76 deletions

diff --git a/Documentation/devicetree/bindings/arm/stm32/st,stm32-syscon.yaml b/Documentation/devicetree/bindings/arm/stm32/st,stm32-syscon.yaml
index b2b156cc160a..ad8e51aa01b0 100644
--- a/Documentation/devicetree/bindings/arm/stm32/st,stm32-syscon.yaml
+++ b/Documentation/devicetree/bindings/arm/stm32/st,stm32-syscon.yaml
@@ -20,6 +20,7 @@ properties:
               - st,stm32-syscfg
               - st,stm32-power-config
               - st,stm32-tamp
+              - st,stm32f4-gcan
           - const: syscon
       - items:
           - const: st,stm32-tamp
@@ -42,6 +43,7 @@ if:
       contains:
         enum:
           - st,stm32mp157-syscfg
+          - st,stm32f4-gcan
 then:
   required:
     - clocks
diff --git a/Documentation/devicetree/bindings/net/can/fsl,flexcan.yaml b/Documentation/devicetree/bindings/net/can/fsl,flexcan.yaml
index 6e59bd2a6094..4162469c3c08 100644
--- a/Documentation/devicetree/bindings/net/can/fsl,flexcan.yaml
+++ b/Documentation/devicetree/bindings/net/can/fsl,flexcan.yaml
@@ -63,6 +63,9 @@ properties:
       boot loader. This property should only be used the used operating system
       doesn't support the clocks and clock-names property.
 
+  power-domains:
+    maxItems: 1
+
   xceiver-supply:
     description: Regulator that powers the CAN transceiver.
 
diff --git a/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
new file mode 100644
index 000000000000..769fa5c27b76
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
@@ -0,0 +1,85 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/can/st,stm32-bxcan.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectronics bxCAN controller
+
+description: STMicroelectronics BxCAN controller for CAN bus
+
+maintainers:
+  - Dario Binacchi <dario.binacchi@amarulasolutions.com>
+
+allOf:
+  - $ref: can-controller.yaml#
+
+properties:
+  compatible:
+    enum:
+      - st,stm32f4-bxcan
+
+  st,can-primary:
+    description:
+      Primary and secondary mode of the bxCAN peripheral is only relevant
+      if the chip has two CAN peripherals. In that case they share some
+      of the required logic.
+      To avoid misunderstandings, it should be noted that ST documentation
+      uses the terms master/slave instead of primary/secondary.
+    type: boolean
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    items:
+      - description: transmit interrupt
+      - description: FIFO 0 receive interrupt
+      - description: FIFO 1 receive interrupt
+      - description: status change error interrupt
+
+  interrupt-names:
+    items:
+      - const: tx
+      - const: rx0
+      - const: rx1
+      - const: sce
+
+  resets:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  st,gcan:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    description:
+      The phandle to the gcan node which allows to access the 512-bytes
+      SRAM memory shared by the two bxCAN cells (CAN1 primary and CAN2
+      secondary) in dual CAN peripheral configuration.
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - resets
+  - clocks
+  - st,gcan
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/stm32fx-clock.h>
+    #include <dt-bindings/mfd/stm32f4-rcc.h>
+
+    can1: can@40006400 {
+        compatible = "st,stm32f4-bxcan";
+        reg = <0x40006400 0x200>;
+        interrupts = <19>, <20>, <21>, <22>;
+        interrupt-names = "tx", "rx0", "rx1", "sce";
+        resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
+        clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
+        st,can-primary;
+        st,gcan = <&gcan>;
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index 7812f0e251ad..cb50c3b5938f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4431,6 +4431,13 @@ S:	Maintained
 F:	drivers/scsi/BusLogic.*
 F:	drivers/scsi/FlashPoint.*
 
+BXCAN CAN NETWORK DRIVER
+M:	Dario Binacchi <dario.binacchi@amarulasolutions.com>
+L:	linux-can@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
+F:	drivers/net/can/bxcan.c
+
 C-MEDIA CMI8788 DRIVER
 M:	Clemens Ladisch <clemens@ladisch.de>
 L:	alsa-devel@alsa-project.org (moderated for non-subscribers)
diff --git a/arch/arm/boot/dts/stm32f4-pinctrl.dtsi b/arch/arm/boot/dts/stm32f4-pinctrl.dtsi
index 4523c63475e4..3bb812d6399e 100644
--- a/arch/arm/boot/dts/stm32f4-pinctrl.dtsi
+++ b/arch/arm/boot/dts/stm32f4-pinctrl.dtsi
@@ -447,6 +447,36 @@
 					slew-rate = <2>;
 				};
 			};
+
+			can1_pins_a: can1-0 {
+				pins1 {
+					pinmux = <STM32_PINMUX('B', 9, AF9)>; /* CAN1_TX */
+				};
+				pins2 {
+					pinmux = <STM32_PINMUX('B', 8, AF9)>; /* CAN1_RX */
+					bias-pull-up;
+				};
+			};
+
+			can2_pins_a: can2-0 {
+				pins1 {
+					pinmux = <STM32_PINMUX('B', 13, AF9)>; /* CAN2_TX */
+				};
+				pins2 {
+					pinmux = <STM32_PINMUX('B', 5, AF9)>; /* CAN2_RX */
+					bias-pull-up;
+				};
+			};
+
+			can2_pins_b: can2-1 {
+				pins1 {
+					pinmux = <STM32_PINMUX('B', 13, AF9)>; /* CAN2_TX */
+				};
+				pins2 {
+					pinmux = <STM32_PINMUX('B', 12, AF9)>; /* CAN2_RX */
+					bias-pull-up;
+				};
+			};
 		};
 	};
 };
diff --git a/arch/arm/boot/dts/stm32f429.dtsi b/arch/arm/boot/dts/stm32f429.dtsi
index c31ceb821231..c9e05e3540d6 100644
--- a/arch/arm/boot/dts/stm32f429.dtsi
+++ b/arch/arm/boot/dts/stm32f429.dtsi
@@ -362,6 +362,35 @@
 			status = "disabled";
 		};
 
+		can1: can@40006400 {
+			compatible = "st,stm32f4-bxcan";
+			reg = <0x40006400 0x200>;
+			interrupts = <19>, <20>, <21>, <22>;
+			interrupt-names = "tx", "rx0", "rx1", "sce";
+			resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
+			clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
+			st,can-primary;
+			st,gcan = <&gcan>;
+			status = "disabled";
+		};
+
+		gcan: gcan@40006600 {
+			compatible = "st,stm32f4-gcan", "syscon";
+			reg = <0x40006600 0x200>;
+			clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
+		};
+
+		can2: can@40006800 {
+			compatible = "st,stm32f4-bxcan";
+			reg = <0x40006800 0x200>;
+			interrupts = <63>, <64>, <65>, <66>;
+			interrupt-names = "tx", "rx0", "rx1", "sce";
+			resets = <&rcc STM32F4_APB1_RESET(CAN2)>;
+			clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN2)>;
+			st,gcan = <&gcan>;
+			status = "disabled";
+		};
+
 		dac: dac@40007400 {
 			compatible = "st,stm32f4-dac-core";
 			reg = <0x40007400 0x400>;
diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index cd34e8dc9394..3ceccafd701b 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -93,6 +93,18 @@ config CAN_AT91
 	  This is a driver for the SoC CAN controller in Atmel's AT91SAM9263
 	  and AT91SAM9X5 processors.
 
+config CAN_BXCAN
+	tristate "STM32 Basic Extended CAN (bxCAN) devices"
+	depends on OF || ARCH_STM32 || COMPILE_TEST
+	depends on HAS_IOMEM
+	select CAN_RX_OFFLOAD
+	help
+	  Say yes here to build support for the STMicroelectronics STM32 basic
+	  extended CAN Controller (bxCAN).
+
+	  This driver can also be built as a module. If so, the module
+	  will be called bxcan.
+
 config CAN_CAN327
 	tristate "Serial / USB serial ELM327 based OBD-II Interfaces (can327)"
 	depends on TTY
diff --git a/drivers/net/can/Makefile b/drivers/net/can/Makefile
index 52b0f6e10668..ff8f76295d13 100644
--- a/drivers/net/can/Makefile
+++ b/drivers/net/can/Makefile
@@ -14,6 +14,7 @@ obj-y				+= usb/
 obj-y				+= softing/
 
 obj-$(CONFIG_CAN_AT91)		+= at91_can.o
+obj-$(CONFIG_CAN_BXCAN)		+= bxcan.o
 obj-$(CONFIG_CAN_CAN327)	+= can327.o
 obj-$(CONFIG_CAN_CC770)		+= cc770/
 obj-$(CONFIG_CAN_C_CAN)		+= c_can/
diff --git a/drivers/net/can/bxcan.c b/drivers/net/can/bxcan.c
new file mode 100644
index 000000000000..e26ccd41e3cb
--- /dev/null
+++ b/drivers/net/can/bxcan.c
@@ -0,0 +1,1098 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// bxcan.c - STM32 Basic Extended CAN controller driver
+//
+// Copyright (c) 2022 Dario Binacchi <dario.binacchi@amarulasolutions.com>
+//
+// NOTE: The ST documentation uses the terms master/slave instead of
+// primary/secondary.
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/bitfield.h>
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/can/rx-offload.h>
+#include <linux/clk.h>
+#include <linux/ethtool.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define BXCAN_NAPI_WEIGHT 3
+#define BXCAN_TIMEOUT_US 10000
+
+#define BXCAN_RX_MB_NUM 2
+#define BXCAN_TX_MB_NUM 3
+
+/* Primary control register (MCR) bits */
+#define BXCAN_MCR_RESET BIT(15)
+#define BXCAN_MCR_TTCM BIT(7)
+#define BXCAN_MCR_ABOM BIT(6)
+#define BXCAN_MCR_AWUM BIT(5)
+#define BXCAN_MCR_NART BIT(4)
+#define BXCAN_MCR_RFLM BIT(3)
+#define BXCAN_MCR_TXFP BIT(2)
+#define BXCAN_MCR_SLEEP BIT(1)
+#define BXCAN_MCR_INRQ BIT(0)
+
+/* Primary status register (MSR) bits */
+#define BXCAN_MSR_ERRI BIT(2)
+#define BXCAN_MSR_SLAK BIT(1)
+#define BXCAN_MSR_INAK BIT(0)
+
+/* Transmit status register (TSR) bits */
+#define BXCAN_TSR_RQCP2 BIT(16)
+#define BXCAN_TSR_RQCP1 BIT(8)
+#define BXCAN_TSR_RQCP0 BIT(0)
+
+/* Receive FIFO 0 register (RF0R) bits */
+#define BXCAN_RF0R_RFOM0 BIT(5)
+#define BXCAN_RF0R_FMP0_MASK GENMASK(1, 0)
+
+/* Interrupt enable register (IER) bits */
+#define BXCAN_IER_SLKIE BIT(17)
+#define BXCAN_IER_WKUIE BIT(16)
+#define BXCAN_IER_ERRIE BIT(15)
+#define BXCAN_IER_LECIE BIT(11)
+#define BXCAN_IER_BOFIE BIT(10)
+#define BXCAN_IER_EPVIE BIT(9)
+#define BXCAN_IER_EWGIE BIT(8)
+#define BXCAN_IER_FOVIE1 BIT(6)
+#define BXCAN_IER_FFIE1 BIT(5)
+#define BXCAN_IER_FMPIE1 BIT(4)
+#define BXCAN_IER_FOVIE0 BIT(3)
+#define BXCAN_IER_FFIE0 BIT(2)
+#define BXCAN_IER_FMPIE0 BIT(1)
+#define BXCAN_IER_TMEIE BIT(0)
+
+/* Error status register (ESR) bits */
+#define BXCAN_ESR_REC_MASK GENMASK(31, 24)
+#define BXCAN_ESR_TEC_MASK GENMASK(23, 16)
+#define BXCAN_ESR_LEC_MASK GENMASK(6, 4)
+#define BXCAN_ESR_BOFF BIT(2)
+#define BXCAN_ESR_EPVF BIT(1)
+#define BXCAN_ESR_EWGF BIT(0)
+
+/* Bit timing register (BTR) bits */
+#define BXCAN_BTR_SILM BIT(31)
+#define BXCAN_BTR_LBKM BIT(30)
+#define BXCAN_BTR_SJW_MASK GENMASK(25, 24)
+#define BXCAN_BTR_TS2_MASK GENMASK(22, 20)
+#define BXCAN_BTR_TS1_MASK GENMASK(19, 16)
+#define BXCAN_BTR_BRP_MASK GENMASK(9, 0)
+
+/* TX mailbox identifier register (TIxR, x = 0..2) bits */
+#define BXCAN_TIxR_STID_MASK GENMASK(31, 21)
+#define BXCAN_TIxR_EXID_MASK GENMASK(31, 3)
+#define BXCAN_TIxR_IDE BIT(2)
+#define BXCAN_TIxR_RTR BIT(1)
+#define BXCAN_TIxR_TXRQ BIT(0)
+
+/* TX mailbox data length and time stamp register (TDTxR, x = 0..2 bits */
+#define BXCAN_TDTxR_DLC_MASK GENMASK(3, 0)
+
+/* RX FIFO mailbox identifier register (RIxR, x = 0..1 */
+#define BXCAN_RIxR_STID_MASK GENMASK(31, 21)
+#define BXCAN_RIxR_EXID_MASK GENMASK(31, 3)
+#define BXCAN_RIxR_IDE BIT(2)
+#define BXCAN_RIxR_RTR BIT(1)
+
+/* RX FIFO mailbox data length and timestamp register (RDTxR, x = 0..1) bits */
+#define BXCAN_RDTxR_TIME_MASK GENMASK(31, 16)
+#define BXCAN_RDTxR_DLC_MASK GENMASK(3, 0)
+
+#define BXCAN_FMR_REG 0x00
+#define BXCAN_FM1R_REG 0x04
+#define BXCAN_FS1R_REG 0x0c
+#define BXCAN_FFA1R_REG 0x14
+#define BXCAN_FA1R_REG 0x1c
+#define BXCAN_FiR1_REG(b) (0x40 + (b) * 8)
+#define BXCAN_FiR2_REG(b) (0x44 + (b) * 8)
+
+#define BXCAN_FILTER_ID(primary) (primary ? 0 : 14)
+
+/* Filter primary register (FMR) bits */
+#define BXCAN_FMR_CANSB_MASK GENMASK(13, 8)
+#define BXCAN_FMR_FINIT BIT(0)
+
+enum bxcan_lec_code {
+	BXCAN_LEC_NO_ERROR = 0,
+	BXCAN_LEC_STUFF_ERROR,
+	BXCAN_LEC_FORM_ERROR,
+	BXCAN_LEC_ACK_ERROR,
+	BXCAN_LEC_BIT1_ERROR,
+	BXCAN_LEC_BIT0_ERROR,
+	BXCAN_LEC_CRC_ERROR,
+	BXCAN_LEC_UNUSED
+};
+
+/* Structure of the message buffer */
+struct bxcan_mb {
+	u32 id;			/* can identifier */
+	u32 dlc;		/* data length control and timestamp */
+	u32 data[2];		/* data */
+};
+
+/* Structure of the hardware registers */
+struct bxcan_regs {
+	u32 mcr;			/* 0x00 - primary control */
+	u32 msr;			/* 0x04 - primary status */
+	u32 tsr;			/* 0x08 - transmit status */
+	u32 rf0r;			/* 0x0c - FIFO 0 */
+	u32 rf1r;			/* 0x10 - FIFO 1 */
+	u32 ier;			/* 0x14 - interrupt enable */
+	u32 esr;			/* 0x18 - error status */
+	u32 btr;			/* 0x1c - bit timing*/
+	u32 reserved0[88];		/* 0x20 */
+	struct bxcan_mb tx_mb[BXCAN_TX_MB_NUM];	/* 0x180 - tx mailbox */
+	struct bxcan_mb rx_mb[BXCAN_RX_MB_NUM];	/* 0x1b0 - rx mailbox */
+};
+
+struct bxcan_priv {
+	struct can_priv can;
+	struct can_rx_offload offload;
+	struct device *dev;
+	struct net_device *ndev;
+
+	struct bxcan_regs __iomem *regs;
+	struct regmap *gcan;
+	int tx_irq;
+	int sce_irq;
+	bool primary;
+	struct clk *clk;
+	spinlock_t rmw_lock;	/* lock for read-modify-write operations */
+	unsigned int tx_head;
+	unsigned int tx_tail;
+	u32 timestamp;
+};
+
+static const struct can_bittiming_const bxcan_bittiming_const = {
+	.name = KBUILD_MODNAME,
+	.tseg1_min = 1,
+	.tseg1_max = 16,
+	.tseg2_min = 1,
+	.tseg2_max = 8,
+	.sjw_max = 4,
+	.brp_min = 1,
+	.brp_max = 1024,
+	.brp_inc = 1,
+};
+
+static inline void bxcan_rmw(struct bxcan_priv *priv, void __iomem *addr,
+			     u32 clear, u32 set)
+{
+	unsigned long flags;
+	u32 old, val;
+
+	spin_lock_irqsave(&priv->rmw_lock, flags);
+	old = readl(addr);
+	val = (old & ~clear) | set;
+	if (val != old)
+		writel(val, addr);
+
+	spin_unlock_irqrestore(&priv->rmw_lock, flags);
+}
+
+static void bxcan_disable_filters(struct bxcan_priv *priv, bool primary)
+{
+	unsigned int fid = BXCAN_FILTER_ID(primary);
+	u32 fmask = BIT(fid);
+
+	regmap_update_bits(priv->gcan, BXCAN_FA1R_REG, fmask, 0);
+}
+
+static void bxcan_enable_filters(struct bxcan_priv *priv, bool primary)
+{
+	unsigned int fid = BXCAN_FILTER_ID(primary);
+	u32 fmask = BIT(fid);
+
+	/* Filter settings:
+	 *
+	 * Accept all messages.
+	 * Assign filter 0 to CAN1 and filter 14 to CAN2 in identifier
+	 * mask mode with 32 bits width.
+	 */
+
+	/* Enter filter initialization mode and assing filters to CAN
+	 * controllers.
+	 */
+	regmap_update_bits(priv->gcan, BXCAN_FMR_REG,
+			   BXCAN_FMR_CANSB_MASK | BXCAN_FMR_FINIT,
+			   FIELD_PREP(BXCAN_FMR_CANSB_MASK, 14) |
+			   BXCAN_FMR_FINIT);
+
+	/* Deactivate filter */
+	regmap_update_bits(priv->gcan, BXCAN_FA1R_REG, fmask, 0);
+
+	/* Two 32-bit registers in identifier mask mode */
+	regmap_update_bits(priv->gcan, BXCAN_FM1R_REG, fmask, 0);
+
+	/* Single 32-bit scale configuration */
+	regmap_update_bits(priv->gcan, BXCAN_FS1R_REG, fmask, fmask);
+
+	/* Assign filter to FIFO 0 */
+	regmap_update_bits(priv->gcan, BXCAN_FFA1R_REG, fmask, 0);
+
+	/* Accept all messages */
+	regmap_write(priv->gcan, BXCAN_FiR1_REG(fid), 0);
+	regmap_write(priv->gcan, BXCAN_FiR2_REG(fid), 0);
+
+	/* Activate filter */
+	regmap_update_bits(priv->gcan, BXCAN_FA1R_REG, fmask, fmask);
+
+	/* Exit filter initialization mode */
+	regmap_update_bits(priv->gcan, BXCAN_FMR_REG, BXCAN_FMR_FINIT, 0);
+}
+
+static inline u8 bxcan_get_tx_head(const struct bxcan_priv *priv)
+{
+	return priv->tx_head % BXCAN_TX_MB_NUM;
+}
+
+static inline u8 bxcan_get_tx_tail(const struct bxcan_priv *priv)
+{
+	return priv->tx_tail % BXCAN_TX_MB_NUM;
+}
+
+static inline u8 bxcan_get_tx_free(const struct bxcan_priv *priv)
+{
+	return BXCAN_TX_MB_NUM - (priv->tx_head - priv->tx_tail);
+}
+
+static bool bxcan_tx_busy(const struct bxcan_priv *priv)
+{
+	if (bxcan_get_tx_free(priv) > 0)
+		return false;
+
+	netif_stop_queue(priv->ndev);
+
+	/* Memory barrier before checking tx_free (head and tail) */
+	smp_mb();
+
+	if (bxcan_get_tx_free(priv) == 0) {
+		netdev_dbg(priv->ndev,
+			   "Stopping tx-queue (tx_head=0x%08x, tx_tail=0x%08x, len=%d).\n",
+			   priv->tx_head, priv->tx_tail,
+			   priv->tx_head - priv->tx_tail);
+
+		return true;
+	}
+
+	netif_start_queue(priv->ndev);
+
+	return false;
+}
+
+static int bxcan_chip_softreset(struct bxcan_priv *priv)
+{
+	struct bxcan_regs __iomem *regs = priv->regs;
+	u32 value;
+
+	bxcan_rmw(priv, &regs->mcr, 0, BXCAN_MCR_RESET);
+	return readx_poll_timeout(readl, &regs->msr, value,
+				  value & BXCAN_MSR_SLAK, BXCAN_TIMEOUT_US,
+				  USEC_PER_SEC);
+}
+
+static int bxcan_enter_init_mode(struct bxcan_priv *priv)
+{
+	struct bxcan_regs __iomem *regs = priv->regs;
+	u32 value;
+
+	bxcan_rmw(priv, &regs->mcr, 0, BXCAN_MCR_INRQ);
+	return readx_poll_timeout(readl, &regs->msr, value,
+				  value & BXCAN_MSR_INAK, BXCAN_TIMEOUT_US,
+				  USEC_PER_SEC);
+}
+
+static int bxcan_leave_init_mode(struct bxcan_priv *priv)
+{
+	struct bxcan_regs __iomem *regs = priv->regs;
+	u32 value;
+
+	bxcan_rmw(priv, &regs->mcr, BXCAN_MCR_INRQ, 0);
+	return readx_poll_timeout(readl, &regs->msr, value,
+				  !(value & BXCAN_MSR_INAK), BXCAN_TIMEOUT_US,
+				  USEC_PER_SEC);
+}
+
+static int bxcan_enter_sleep_mode(struct bxcan_priv *priv)
+{
+	struct bxcan_regs __iomem *regs = priv->regs;
+	u32 value;
+
+	bxcan_rmw(priv, &regs->mcr, 0, BXCAN_MCR_SLEEP);
+	return readx_poll_timeout(readl, &regs->msr, value,
+				  value & BXCAN_MSR_SLAK, BXCAN_TIMEOUT_US,
+				  USEC_PER_SEC);
+}
+
+static int bxcan_leave_sleep_mode(struct bxcan_priv *priv)
+{
+	struct bxcan_regs __iomem *regs = priv->regs;
+	u32 value;
+
+	bxcan_rmw(priv, &regs->mcr, BXCAN_MCR_SLEEP, 0);
+	return readx_poll_timeout(readl, &regs->msr, value,
+				  !(value & BXCAN_MSR_SLAK), BXCAN_TIMEOUT_US,
+				  USEC_PER_SEC);
+}
+
+static inline
+struct bxcan_priv *rx_offload_to_priv(struct can_rx_offload *offload)
+{
+	return container_of(offload, struct bxcan_priv, offload);
+}
+
+static struct sk_buff *bxcan_mailbox_read(struct can_rx_offload *offload,
+					  unsigned int mbxno, u32 *timestamp,
+					  bool drop)
+{
+	struct bxcan_priv *priv = rx_offload_to_priv(offload);
+	struct bxcan_regs __iomem *regs = priv->regs;
+	struct bxcan_mb __iomem *mb_regs = &regs->rx_mb[0];
+	struct sk_buff *skb = NULL;
+	struct can_frame *cf;
+	u32 rf0r, id, dlc;
+
+	rf0r = readl(&regs->rf0r);
+	if (unlikely(drop)) {
+		skb = ERR_PTR(-ENOBUFS);
+		goto mark_as_read;
+	}
+
+	if (!(rf0r & BXCAN_RF0R_FMP0_MASK))
+		goto mark_as_read;
+
+	skb = alloc_can_skb(offload->dev, &cf);
+	if (unlikely(!skb)) {
+		skb = ERR_PTR(-ENOMEM);
+		goto mark_as_read;
+	}
+
+	id = readl(&mb_regs->id);
+	if (id & BXCAN_RIxR_IDE)
+		cf->can_id = FIELD_GET(BXCAN_RIxR_EXID_MASK, id) | CAN_EFF_FLAG;
+	else
+		cf->can_id = FIELD_GET(BXCAN_RIxR_STID_MASK, id) & CAN_SFF_MASK;
+
+	dlc = readl(&mb_regs->dlc);
+	priv->timestamp = FIELD_GET(BXCAN_RDTxR_TIME_MASK, dlc);
+	cf->len = can_cc_dlc2len(FIELD_GET(BXCAN_RDTxR_DLC_MASK, dlc));
+
+	if (id & BXCAN_RIxR_RTR) {
+		cf->can_id |= CAN_RTR_FLAG;
+	} else {
+		int i, j;
+
+		for (i = 0, j = 0; i < cf->len; i += 4, j++)
+			*(u32 *)(cf->data + i) = readl(&mb_regs->data[j]);
+	}
+
+ mark_as_read:
+	rf0r |= BXCAN_RF0R_RFOM0;
+	writel(rf0r, &regs->rf0r);
+	return skb;
+}
+
+static irqreturn_t bxcan_rx_isr(int irq, void *dev_id)
+{
+	struct net_device *ndev = dev_id;
+	struct bxcan_priv *priv = netdev_priv(ndev);
+	struct bxcan_regs __iomem *regs = priv->regs;
+	u32 rf0r;
+
+	rf0r = readl(&regs->rf0r);
+	if (!(rf0r & BXCAN_RF0R_FMP0_MASK))
+		return IRQ_NONE;
+
+	can_rx_offload_irq_offload_fifo(&priv->offload);
+	can_rx_offload_irq_finish(&priv->offload);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t bxcan_tx_isr(int irq, void *dev_id)
+{
+	struct net_device *ndev = dev_id;
+	struct bxcan_priv *priv = netdev_priv(ndev);
+	struct bxcan_regs __iomem *regs = priv->regs;
+	struct net_device_stats *stats = &ndev->stats;
+	u32 tsr, rqcp_bit;
+	int idx;
+
+	tsr = readl(&regs->tsr);
+	if (!(tsr & (BXCAN_TSR_RQCP0 | BXCAN_TSR_RQCP1 | BXCAN_TSR_RQCP2)))
+		return IRQ_NONE;
+
+	while (priv->tx_head - priv->tx_tail > 0) {
+		idx = bxcan_get_tx_tail(priv);
+		rqcp_bit = BXCAN_TSR_RQCP0 << (idx << 3);
+		if (!(tsr & rqcp_bit))
+			break;
+
+		stats->tx_packets++;
+		stats->tx_bytes += can_get_echo_skb(ndev, idx, NULL);
+		priv->tx_tail++;
+	}
+
+	writel(tsr, &regs->tsr);
+
+	if (bxcan_get_tx_free(priv)) {
+		/* Make sure that anybody stopping the queue after
+		 * this sees the new tx_ring->tail.
+		 */
+		smp_mb();
+		netif_wake_queue(ndev);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void bxcan_handle_state_change(struct net_device *ndev, u32 esr)
+{
+	struct bxcan_priv *priv = netdev_priv(ndev);
+	enum can_state new_state = priv->can.state;
+	struct can_berr_counter bec;
+	enum can_state rx_state, tx_state;
+	struct sk_buff *skb;
+	struct can_frame *cf;
+
+	/* Early exit if no error flag is set */
+	if (!(esr & (BXCAN_ESR_EWGF | BXCAN_ESR_EPVF | BXCAN_ESR_BOFF)))
+		return;
+
+	bec.txerr = FIELD_GET(BXCAN_ESR_TEC_MASK, esr);
+	bec.rxerr = FIELD_GET(BXCAN_ESR_REC_MASK, esr);
+
+	if (esr & BXCAN_ESR_BOFF)
+		new_state = CAN_STATE_BUS_OFF;
+	else if (esr & BXCAN_ESR_EPVF)
+		new_state = CAN_STATE_ERROR_PASSIVE;
+	else if (esr & BXCAN_ESR_EWGF)
+		new_state = CAN_STATE_ERROR_WARNING;
+
+	/* state hasn't changed */
+	if (unlikely(new_state == priv->can.state))
+		return;
+
+	skb = alloc_can_err_skb(ndev, &cf);
+
+	tx_state = bec.txerr >= bec.rxerr ? new_state : 0;
+	rx_state = bec.txerr <= bec.rxerr ? new_state : 0;
+	can_change_state(ndev, cf, tx_state, rx_state);
+
+	if (new_state == CAN_STATE_BUS_OFF) {
+		can_bus_off(ndev);
+	} else if (skb) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = bec.txerr;
+		cf->data[7] = bec.rxerr;
+	}
+
+	if (skb) {
+		int err;
+
+		err = can_rx_offload_queue_timestamp(&priv->offload, skb,
+						     priv->timestamp);
+		if (err)
+			ndev->stats.rx_fifo_errors++;
+	}
+}
+
+static void bxcan_handle_bus_err(struct net_device *ndev, u32 esr)
+{
+	struct bxcan_priv *priv = netdev_priv(ndev);
+	enum bxcan_lec_code lec_code;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+
+	lec_code = FIELD_GET(BXCAN_ESR_LEC_MASK, esr);
+
+	/* Early exit if no lec update or no error.
+	 * No lec update means that no CAN bus event has been detected
+	 * since CPU wrote BXCAN_LEC_UNUSED value to status reg.
+	 */
+	if (lec_code == BXCAN_LEC_UNUSED || lec_code == BXCAN_LEC_NO_ERROR)
+		return;
+
+	/* Common for all type of bus errors */
+	priv->can.can_stats.bus_error++;
+
+	/* Propagate the error condition to the CAN stack */
+	skb = alloc_can_err_skb(ndev, &cf);
+	if (skb)
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+
+	switch (lec_code) {
+	case BXCAN_LEC_STUFF_ERROR:
+		netdev_dbg(ndev, "Stuff error\n");
+		ndev->stats.rx_errors++;
+		if (skb)
+			cf->data[2] |= CAN_ERR_PROT_STUFF;
+		break;
+
+	case BXCAN_LEC_FORM_ERROR:
+		netdev_dbg(ndev, "Form error\n");
+		ndev->stats.rx_errors++;
+		if (skb)
+			cf->data[2] |= CAN_ERR_PROT_FORM;
+		break;
+
+	case BXCAN_LEC_ACK_ERROR:
+		netdev_dbg(ndev, "Ack error\n");
+		ndev->stats.tx_errors++;
+		if (skb) {
+			cf->can_id |= CAN_ERR_ACK;
+			cf->data[3] = CAN_ERR_PROT_LOC_ACK;
+		}
+		break;
+
+	case BXCAN_LEC_BIT1_ERROR:
+		netdev_dbg(ndev, "Bit error (recessive)\n");
+		ndev->stats.tx_errors++;
+		if (skb)
+			cf->data[2] |= CAN_ERR_PROT_BIT1;
+		break;
+
+	case BXCAN_LEC_BIT0_ERROR:
+		netdev_dbg(ndev, "Bit error (dominant)\n");
+		ndev->stats.tx_errors++;
+		if (skb)
+			cf->data[2] |= CAN_ERR_PROT_BIT0;
+		break;
+
+	case BXCAN_LEC_CRC_ERROR:
+		netdev_dbg(ndev, "CRC error\n");
+		ndev->stats.rx_errors++;
+		if (skb) {
+			cf->data[2] |= CAN_ERR_PROT_BIT;
+			cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
+		}
+		break;
+
+	default:
+		break;
+	}
+
+	if (skb) {
+		int err;
+
+		err = can_rx_offload_queue_timestamp(&priv->offload, skb,
+						     priv->timestamp);
+		if (err)
+			ndev->stats.rx_fifo_errors++;
+	}
+}
+
+static irqreturn_t bxcan_state_change_isr(int irq, void *dev_id)
+{
+	struct net_device *ndev = dev_id;
+	struct bxcan_priv *priv = netdev_priv(ndev);
+	struct bxcan_regs __iomem *regs = priv->regs;
+	u32 msr, esr;
+
+	msr = readl(&regs->msr);
+	if (!(msr & BXCAN_MSR_ERRI))
+		return IRQ_NONE;
+
+	esr = readl(&regs->esr);
+	bxcan_handle_state_change(ndev, esr);
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
+		bxcan_handle_bus_err(ndev, esr);
+
+	msr |= BXCAN_MSR_ERRI;
+	writel(msr, &regs->msr);
+	can_rx_offload_irq_finish(&priv->offload);
+
+	return IRQ_HANDLED;
+}
+
+static int bxcan_chip_start(struct net_device *ndev)
+{
+	struct bxcan_priv *priv = netdev_priv(ndev);
+	struct bxcan_regs __iomem *regs = priv->regs;
+	struct can_bittiming *bt = &priv->can.bittiming;
+	u32 clr, set;
+	int err;
+
+	err = bxcan_chip_softreset(priv);
+	if (err) {
+		netdev_err(ndev, "failed to reset chip, error %pe\n",
+			   ERR_PTR(err));
+		return err;
+	}
+
+	err = bxcan_leave_sleep_mode(priv);
+	if (err) {
+		netdev_err(ndev, "failed to leave sleep mode, error %pe\n",
+			   ERR_PTR(err));
+		goto failed_leave_sleep;
+	}
+
+	err = bxcan_enter_init_mode(priv);
+	if (err) {
+		netdev_err(ndev, "failed to enter init mode, error %pe\n",
+			   ERR_PTR(err));
+		goto failed_enter_init;
+	}
+
+	/* MCR
+	 *
+	 * select request order priority
+	 * enable time triggered mode
+	 * bus-off state left on sw request
+	 * sleep mode left on sw request
+	 * retransmit automatically on error
+	 * do not lock RX FIFO on overrun
+	 */
+	bxcan_rmw(priv, &regs->mcr,
+		  BXCAN_MCR_ABOM | BXCAN_MCR_AWUM | BXCAN_MCR_NART |
+		  BXCAN_MCR_RFLM, BXCAN_MCR_TTCM | BXCAN_MCR_TXFP);
+
+	/* Bit timing register settings */
+	set = FIELD_PREP(BXCAN_BTR_BRP_MASK, bt->brp - 1) |
+		FIELD_PREP(BXCAN_BTR_TS1_MASK, bt->phase_seg1 +
+			   bt->prop_seg - 1) |
+		FIELD_PREP(BXCAN_BTR_TS2_MASK, bt->phase_seg2 - 1) |
+		FIELD_PREP(BXCAN_BTR_SJW_MASK, bt->sjw - 1);
+
+	/* loopback + silent mode put the controller in test mode,
+	 * useful for hot self-test
+	 */
+	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
+		set |= BXCAN_BTR_LBKM;
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+		set |= BXCAN_BTR_SILM;
+
+	bxcan_rmw(priv, &regs->btr, BXCAN_BTR_SILM | BXCAN_BTR_LBKM |
+		  BXCAN_BTR_BRP_MASK | BXCAN_BTR_TS1_MASK | BXCAN_BTR_TS2_MASK |
+		  BXCAN_BTR_SJW_MASK, set);
+
+	bxcan_enable_filters(priv, priv->primary);
+
+	/* Clear all internal status */
+	priv->tx_head = 0;
+	priv->tx_tail = 0;
+
+	err = bxcan_leave_init_mode(priv);
+	if (err) {
+		netdev_err(ndev, "failed to leave init mode, error %pe\n",
+			   ERR_PTR(err));
+		goto failed_leave_init;
+	}
+
+	/* Set a `lec` value so that we can check for updates later */
+	bxcan_rmw(priv, &regs->esr, BXCAN_ESR_LEC_MASK,
+		  FIELD_PREP(BXCAN_ESR_LEC_MASK, BXCAN_LEC_UNUSED));
+
+	/* IER
+	 *
+	 * Enable interrupt for:
+	 * bus-off
+	 * passive error
+	 * warning error
+	 * last error code
+	 * RX FIFO pending message
+	 * TX mailbox empty
+	 */
+	clr = BXCAN_IER_WKUIE | BXCAN_IER_SLKIE |  BXCAN_IER_FOVIE1 |
+		BXCAN_IER_FFIE1 | BXCAN_IER_FMPIE1 | BXCAN_IER_FOVIE0 |
+		BXCAN_IER_FFIE0;
+	set = BXCAN_IER_ERRIE | BXCAN_IER_BOFIE | BXCAN_IER_EPVIE |
+		BXCAN_IER_EWGIE | BXCAN_IER_FMPIE0 | BXCAN_IER_TMEIE;
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
+		set |= BXCAN_IER_LECIE;