Merge tag 'linux-can-next-for-5.18-20220313' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

linux-can-next-for-5.18-20220313

Marc Kleine-Budde says:

====================
pull-request: can-next 2022-03-13

this is a pull request of 13 patches for net-next/master.

The 1st patch is by me and fixes the freeing of a skb in the vxcan
driver (initially added in this net-next window).

The remaining 12 patches are also by me and target the mcp251xfd
driver. The first patch fixes a printf modifier (initially added in
this net-next window). The remaining patches add ethtool based ring
and RX/TX IRQ coalescing support to the driver.
====================

Signed-off-by: David S. Miller <[e-mail]>

drivers/net/can/spi/mcp251xfd/Makefile

···
 mcp251xfd-objs += mcp251xfd-chip-fifo.o
 mcp251xfd-objs += mcp251xfd-core.o
 mcp251xfd-objs += mcp251xfd-crc16.o
+mcp251xfd-objs += mcp251xfd-ethtool.o
+mcp251xfd-objs += mcp251xfd-ram.o
 mcp251xfd-objs += mcp251xfd-regmap.o
 mcp251xfd-objs += mcp251xfd-ring.o
 mcp251xfd-objs += mcp251xfd-rx.o

drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c

···
 		goto out_transceiver_disable;
 
 	mcp251xfd_timestamp_init(priv);
+	clear_bit(MCP251XFD_FLAGS_DOWN, priv->flags);
 	can_rx_offload_enable(&priv->offload);
 
 	err = request_threaded_irq(spi->irq, NULL, mcp251xfd_irq,
···
 	free_irq(spi->irq, priv);
  out_can_rx_offload_disable:
 	can_rx_offload_disable(&priv->offload);
+	set_bit(MCP251XFD_FLAGS_DOWN, priv->flags);
 	mcp251xfd_timestamp_stop(priv);
  out_transceiver_disable:
 	mcp251xfd_transceiver_disable(priv);
···
 	struct mcp251xfd_priv *priv = netdev_priv(ndev);
 
 	netif_stop_queue(ndev);
+	set_bit(MCP251XFD_FLAGS_DOWN, priv->flags);
+	hrtimer_cancel(&priv->rx_irq_timer);
 	mcp251xfd_chip_interrupts_disable(priv);
 	free_irq(ndev->irq, priv);
 	can_rx_offload_disable(&priv->offload);
···
 	if (err)
 		goto out_chip_sleep;
 
+	mcp251xfd_ethtool_init(priv);
+
 	err = register_candev(ndev);
 	if (err)
 		goto out_chip_sleep;
···
 		CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_BERR_REPORTING |
 		CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO |
 		CAN_CTRLMODE_CC_LEN8_DLC;
+	set_bit(MCP251XFD_FLAGS_DOWN, priv->flags);
 	priv->ndev = ndev;
 	priv->spi = spi;
 	priv->rx_int = rx_int;

drivers/net/can/spi/mcp251xfd/mcp251xfd-ethtool.c

···
+// SPDX-License-Identifier: GPL-2.0
+//
+// mcp251xfd - Microchip MCP251xFD Family CAN controller driver
+//
+// Copyright (c) 2021, 2022 Pengutronix,
+//               Marc Kleine-Budde <[e-mail]>
+//
+
+#include <linux/ethtool.h>
+
+#include "mcp251xfd.h"
+#include "mcp251xfd-ram.h"
+
+static void
+mcp251xfd_ring_get_ringparam(struct net_device *ndev,
+			     struct ethtool_ringparam *ring,
+			     struct kernel_ethtool_ringparam *kernel_ring,
+			     struct netlink_ext_ack *extack)
+{
+	const struct mcp251xfd_priv *priv = netdev_priv(ndev);
+	const bool fd_mode = mcp251xfd_is_fd_mode(priv);
+	struct can_ram_layout layout;
+
+	can_ram_get_layout(&layout, &mcp251xfd_ram_config, NULL, NULL, fd_mode);
+	ring->rx_max_pending = layout.max_rx;
+	ring->tx_max_pending = layout.max_tx;
+
+	ring->rx_pending = priv->rx_obj_num;
+	ring->tx_pending = priv->tx->obj_num;
+}
+
+static int
+mcp251xfd_ring_set_ringparam(struct net_device *ndev,
+			     struct ethtool_ringparam *ring,
+			     struct kernel_ethtool_ringparam *kernel_ring,
+			     struct netlink_ext_ack *extack)
+{
+	struct mcp251xfd_priv *priv = netdev_priv(ndev);
+	const bool fd_mode = mcp251xfd_is_fd_mode(priv);
+	struct can_ram_layout layout;
+
+	can_ram_get_layout(&layout, &mcp251xfd_ram_config, ring, NULL, fd_mode);
+	if ((layout.cur_rx != priv->rx_obj_num ||
+	     layout.cur_tx != priv->tx->obj_num) &&
+	    netif_running(ndev))
+		return -EBUSY;
+
+	priv->rx_obj_num = layout.cur_rx;
+	priv->rx_obj_num_coalesce_irq = layout.rx_coalesce;
+	priv->tx->obj_num = layout.cur_tx;
+
+	return 0;
+}
+
+static int mcp251xfd_ring_get_coalesce(struct net_device *ndev,
+				       struct ethtool_coalesce *ec,
+				       struct kernel_ethtool_coalesce *kec,
+				       struct netlink_ext_ack *ext_ack)
+{
+	struct mcp251xfd_priv *priv = netdev_priv(ndev);
+	u32 rx_max_frames, tx_max_frames;
+
+	/* The ethtool doc says:
+	 * To disable coalescing, set usecs = 0 and max_frames = 1.
+	 */
+	if (priv->rx_obj_num_coalesce_irq == 0)
+		rx_max_frames = 1;
+	else
+		rx_max_frames = priv->rx_obj_num_coalesce_irq;
+
+	ec->rx_max_coalesced_frames_irq = rx_max_frames;
+	ec->rx_coalesce_usecs_irq = priv->rx_coalesce_usecs_irq;
+
+	if (priv->tx_obj_num_coalesce_irq == 0)
+		tx_max_frames = 1;
+	else
+		tx_max_frames = priv->tx_obj_num_coalesce_irq;
+
+	ec->tx_max_coalesced_frames_irq = tx_max_frames;
+	ec->tx_coalesce_usecs_irq = priv->tx_coalesce_usecs_irq;
+
+	return 0;
+}
+
+static int mcp251xfd_ring_set_coalesce(struct net_device *ndev,
+				       struct ethtool_coalesce *ec,
+				       struct kernel_ethtool_coalesce *kec,
+				       struct netlink_ext_ack *ext_ack)
+{
+	struct mcp251xfd_priv *priv = netdev_priv(ndev);
+	const bool fd_mode = mcp251xfd_is_fd_mode(priv);
+	const struct ethtool_ringparam ring = {
+		.rx_pending = priv->rx_obj_num,
+		.tx_pending = priv->tx->obj_num,
+	};
+	struct can_ram_layout layout;
+
+	can_ram_get_layout(&layout, &mcp251xfd_ram_config, &ring, ec, fd_mode);
+
+	if ((layout.rx_coalesce != priv->rx_obj_num_coalesce_irq ||
+	     ec->rx_coalesce_usecs_irq != priv->rx_coalesce_usecs_irq ||
+	     layout.tx_coalesce != priv->tx_obj_num_coalesce_irq ||
+	     ec->tx_coalesce_usecs_irq != priv->tx_coalesce_usecs_irq) &&
+	    netif_running(ndev))
+		return -EBUSY;
+
+	priv->rx_obj_num = layout.cur_rx;
+	priv->rx_obj_num_coalesce_irq = layout.rx_coalesce;
+	priv->rx_coalesce_usecs_irq = ec->rx_coalesce_usecs_irq;
+
+	priv->tx->obj_num = layout.cur_tx;
+	priv->tx_obj_num_coalesce_irq = layout.tx_coalesce;
+	priv->tx_coalesce_usecs_irq = ec->tx_coalesce_usecs_irq;
+
+	return 0;
+}
+
+static const struct ethtool_ops mcp251xfd_ethtool_ops = {
+	.supported_coalesce_params = ETHTOOL_COALESCE_RX_USECS_IRQ |
+		ETHTOOL_COALESCE_RX_MAX_FRAMES_IRQ |
+		ETHTOOL_COALESCE_TX_USECS_IRQ |
+		ETHTOOL_COALESCE_TX_MAX_FRAMES_IRQ,
+	.get_ringparam = mcp251xfd_ring_get_ringparam,
+	.set_ringparam = mcp251xfd_ring_set_ringparam,
+	.get_coalesce = mcp251xfd_ring_get_coalesce,
+	.set_coalesce = mcp251xfd_ring_set_coalesce,
+};
+
+void mcp251xfd_ethtool_init(struct mcp251xfd_priv *priv)
+{
+	struct can_ram_layout layout;
+
+	priv->ndev->ethtool_ops = &mcp251xfd_ethtool_ops;
+
+	can_ram_get_layout(&layout, &mcp251xfd_ram_config, NULL, NULL, false);
+	priv->rx_obj_num = layout.default_rx;
+	priv->tx->obj_num = layout.default_tx;
+
+	priv->rx_obj_num_coalesce_irq = 0;
+	priv->tx_obj_num_coalesce_irq = 0;
+	priv->rx_coalesce_usecs_irq = 0;
+	priv->tx_coalesce_usecs_irq = 0;
+}

drivers/net/can/spi/mcp251xfd/mcp251xfd-ram.c

···
+// SPDX-License-Identifier: GPL-2.0
+//
+// mcp251xfd - Microchip MCP251xFD Family CAN controller driver
+//
+// Copyright (c) 2021, 2022 Pengutronix,
+//               Marc Kleine-Budde <[e-mail]>
+//
+
+#include "mcp251xfd-ram.h"
+
+static inline u8 can_ram_clamp(const struct can_ram_config *config,
+			       const struct can_ram_obj_config *obj,
+			       u8 val)
+{
+	u8 max;
+
+	max = min_t(u8, obj->max, obj->fifo_num * config->fifo_depth);
+	return clamp(val, obj->min, max);
+}
+
+static u8
+can_ram_rounddown_pow_of_two(const struct can_ram_config *config,
+			     const struct can_ram_obj_config *obj,
+			     const u8 coalesce, u8 val)
+{
+	u8 fifo_num = obj->fifo_num;
+	u8 ret = 0, i;
+
+	val = can_ram_clamp(config, obj, val);
+
+	if (coalesce) {
+		/* Use 1st FIFO for coalescing, if requested.
+		 *
+		 * Either use complete FIFO (and FIFO Full IRQ) for
+		 * coalescing or only half of FIFO (FIFO Half Full
+		 * IRQ) and use remaining half for normal objects.
+		 */
+		ret = min_t(u8, coalesce * 2, config->fifo_depth);
+		val -= ret;
+		fifo_num--;
+	}
+
+	for (i = 0; i < fifo_num && val; i++) {
+		u8 n;
+
+		n = min_t(u8, rounddown_pow_of_two(val),
+			  config->fifo_depth);
+
+		/* skip small FIFOs */
+		if (n < obj->fifo_depth_min)
+			return ret;
+
+		ret += n;
+		val -= n;
+	}
+
+	return ret;
+}
+
+void can_ram_get_layout(struct can_ram_layout *layout,
+			const struct can_ram_config *config,
+			const struct ethtool_ringparam *ring,
+			const struct ethtool_coalesce *ec,
+			const bool fd_mode)
+{
+	u8 num_rx, num_tx;
+	u16 ram_free;
+
+	/* default CAN */
+
+	num_tx = config->tx.def[fd_mode];
+	num_tx = can_ram_rounddown_pow_of_two(config, &config->tx, 0, num_tx);
+
+	ram_free = config->size;
+	ram_free -= config->tx.size[fd_mode] * num_tx;
+
+	num_rx = ram_free / config->rx.size[fd_mode];
+
+	layout->default_rx = can_ram_rounddown_pow_of_two(config, &config->rx, 0, num_rx);
+	layout->default_tx = num_tx;
+
+	/* MAX CAN */
+
+	ram_free = config->size;
+	ram_free -= config->tx.size[fd_mode] * config->tx.min;
+	num_rx = ram_free / config->rx.size[fd_mode];
+
+	ram_free = config->size;
+	ram_free -= config->rx.size[fd_mode] * config->rx.min;
+	num_tx = ram_free / config->tx.size[fd_mode];
+
+	layout->max_rx = can_ram_rounddown_pow_of_two(config, &config->rx, 0, num_rx);
+	layout->max_tx = can_ram_rounddown_pow_of_two(config, &config->tx, 0, num_tx);
+
+	/* cur CAN */
+
+	if (ring) {
+		u8 num_rx_coalesce = 0, num_tx_coalesce = 0;
+
+		num_rx = can_ram_rounddown_pow_of_two(config, &config->rx, 0, ring->rx_pending);
+
+		/* The ethtool doc says:
+		 * To disable coalescing, set usecs = 0 and max_frames = 1.
+		 */
+		if (ec && !(ec->rx_coalesce_usecs_irq == 0 &&
+			    ec->rx_max_coalesced_frames_irq == 1)) {
+			u8 max;
+
+			/* use only max half of available objects for coalescing */
+			max = min_t(u8, num_rx / 2, config->fifo_depth);
+			num_rx_coalesce = clamp(ec->rx_max_coalesced_frames_irq,
+						(u32)config->rx.fifo_depth_coalesce_min,
+						(u32)max);
+			num_rx_coalesce = rounddown_pow_of_two(num_rx_coalesce);
+
+			num_rx = can_ram_rounddown_pow_of_two(config, &config->rx,
+							      num_rx_coalesce, num_rx);
+		}
+
+		ram_free = config->size - config->rx.size[fd_mode] * num_rx;
+		num_tx = ram_free / config->tx.size[fd_mode];
+		num_tx = min_t(u8, ring->tx_pending, num_tx);
+		num_tx = can_ram_rounddown_pow_of_two(config, &config->tx, 0, num_tx);
+
+		/* The ethtool doc says:
+		 * To disable coalescing, set usecs = 0 and max_frames = 1.
+		 */
+		if (ec && !(ec->tx_coalesce_usecs_irq == 0 &&
+			    ec->tx_max_coalesced_frames_irq == 1)) {
+			u8 max;
+
+			/* use only max half of available objects for coalescing */
+			max = min_t(u8, num_tx / 2, config->fifo_depth);
+			num_tx_coalesce = clamp(ec->tx_max_coalesced_frames_irq,
+						(u32)config->tx.fifo_depth_coalesce_min,
+						(u32)max);
+			num_tx_coalesce = rounddown_pow_of_two(num_tx_coalesce);
+
+			num_tx = can_ram_rounddown_pow_of_two(config, &config->tx,
+							      num_tx_coalesce, num_tx);
+		}
+
+		layout->cur_rx = num_rx;
+		layout->cur_tx = num_tx;
+		layout->rx_coalesce = num_rx_coalesce;
+		layout->tx_coalesce = num_tx_coalesce;
+	} else {
+		layout->cur_rx = layout->default_rx;
+		layout->cur_tx = layout->default_tx;
+		layout->rx_coalesce = 0;
+		layout->tx_coalesce = 0;
+	}
+}

drivers/net/can/spi/mcp251xfd/mcp251xfd-ram.h

···
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * mcp251xfd - Microchip MCP251xFD Family CAN controller driver
+ *
+ * Copyright (c) 2021, 2022 Pengutronix,
+ *               Marc Kleine-Budde <[e-mail]>
+ */
+
+#ifndef _MCP251XFD_RAM_H
+#define _MCP251XFD_RAM_H
+
+#include <linux/ethtool.h>
+
+#define CAN_RAM_NUM_MAX (-1)
+
+enum can_ram_mode {
+	CAN_RAM_MODE_CAN,
+	CAN_RAM_MODE_CANFD,
+	__CAN_RAM_MODE_MAX
+};
+
+struct can_ram_obj_config {
+	u8 size[__CAN_RAM_MODE_MAX];
+
+	u8 def[__CAN_RAM_MODE_MAX];
+	u8 min;
+	u8 max;
+
+	u8 fifo_num;
+	u8 fifo_depth_min;
+	u8 fifo_depth_coalesce_min;
+};
+
+struct can_ram_config {
+	const struct can_ram_obj_config rx;
+	const struct can_ram_obj_config tx;
+
+	u16 size;
+	u8 fifo_depth;
+};
+
+struct can_ram_layout {
+	u8 default_rx;
+	u8 default_tx;
+
+	u8 max_rx;
+	u8 max_tx;
+
+	u8 cur_rx;
+	u8 cur_tx;
+
+	u8 rx_coalesce;
+	u8 tx_coalesce;
+};
+
+void can_ram_get_layout(struct can_ram_layout *layout,
+			const struct can_ram_config *config,
+			const struct ethtool_ringparam *ring,
+			const struct ethtool_coalesce *ec,
+			const bool fd_mode);
+
+#endif

drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c

···
 #include <asm/unaligned.h>
 
 #include "mcp251xfd.h"
+#include "mcp251xfd-ram.h"
 
 static inline u8
 mcp251xfd_cmd_prepare_write_reg(const struct mcp251xfd_priv *priv,
···
 	/* TEF- and TX-FIFO have same number of objects */
 	*base = mcp251xfd_get_tef_obj_addr(priv->tx->obj_num);
 
+	/* FIFO IRQ enable */
+	addr = MCP251XFD_REG_TEFCON;
+	val = MCP251XFD_REG_TEFCON_TEFOVIE | MCP251XFD_REG_TEFCON_TEFNEIE;
+
+	len = mcp251xfd_cmd_prepare_write_reg(priv, &tef_ring->irq_enable_buf,
+					      addr, val, val);
+	tef_ring->irq_enable_xfer.tx_buf = &tef_ring->irq_enable_buf;
+	tef_ring->irq_enable_xfer.len = len;
+	spi_message_init_with_transfers(&tef_ring->irq_enable_msg,
+					&tef_ring->irq_enable_xfer, 1);
+
 	/* FIFO increment TEF tail pointer */
 	addr = MCP251XFD_REG_TEFCON;
 	val = MCP251XFD_REG_TEFCON_UINC;
···
 	 * message.
 	 */
 	xfer->cs_change = 0;
+
+	if (priv->tx_coalesce_usecs_irq || priv->tx_obj_num_coalesce_irq) {
+		val = MCP251XFD_REG_TEFCON_UINC |
+			MCP251XFD_REG_TEFCON_TEFOVIE |
+			MCP251XFD_REG_TEFCON_TEFHIE;
+
+		len = mcp251xfd_cmd_prepare_write_reg(priv,
+						      &tef_ring->uinc_irq_disable_buf,
+						      addr, val, val);
+		xfer->tx_buf = &tef_ring->uinc_irq_disable_buf;
+		xfer->len = len;
+	}
 }
 
 static void
···
 		*base = mcp251xfd_get_rx_obj_addr(rx_ring, rx_ring->obj_num);
 		*fifo_nr += 1;
 
-		/* FIFO increment RX tail pointer */
+		/* FIFO IRQ enable */
 		addr = MCP251XFD_REG_FIFOCON(rx_ring->fifo_nr);
+		val = MCP251XFD_REG_FIFOCON_RXOVIE |
+			MCP251XFD_REG_FIFOCON_TFNRFNIE;
+		len = mcp251xfd_cmd_prepare_write_reg(priv, &rx_ring->irq_enable_buf,
+						      addr, val, val);
+		rx_ring->irq_enable_xfer.tx_buf = &rx_ring->irq_enable_buf;
+		rx_ring->irq_enable_xfer.len = len;
+		spi_message_init_with_transfers(&rx_ring->irq_enable_msg,
+						&rx_ring->irq_enable_xfer, 1);
+
+		/* FIFO increment RX tail pointer */
 		val = MCP251XFD_REG_FIFOCON_UINC;
 		len = mcp251xfd_cmd_prepare_write_reg(priv, &rx_ring->uinc_buf,
 						      addr, val, val);
···
 		 * the chip select at the end of the message.
 		 */
 		xfer->cs_change = 0;
+
+		/* Use 1st RX-FIFO for IRQ coalescing. If enabled
+		 * (rx_coalesce_usecs_irq or rx_max_coalesce_frames_irq
+		 * is activated), use the last transfer to disable:
+		 *
+		 * - TFNRFNIE (Receive FIFO Not Empty Interrupt)
+		 *
+		 * and enable:
+		 *
+		 * - TFHRFHIE (Receive FIFO Half Full Interrupt)
+		 *   - or -
+		 * - TFERFFIE (Receive FIFO Full Interrupt)
+		 *
+		 * depending on rx_max_coalesce_frames_irq.
+		 *
+		 * The RXOVIE (Overflow Interrupt) is always enabled.
+		 */
+		if (rx_ring->nr == 0 && (priv->rx_coalesce_usecs_irq ||
+					 priv->rx_obj_num_coalesce_irq)) {
+			val = MCP251XFD_REG_FIFOCON_UINC |
+				MCP251XFD_REG_FIFOCON_RXOVIE;
+
+			if (priv->rx_obj_num_coalesce_irq == rx_ring->obj_num)
+				val |= MCP251XFD_REG_FIFOCON_TFERFFIE;
+			else if (priv->rx_obj_num_coalesce_irq)
+				val |= MCP251XFD_REG_FIFOCON_TFHRFHIE;
+
+			len = mcp251xfd_cmd_prepare_write_reg(priv,
+							      &rx_ring->uinc_irq_disable_buf,
+							      addr, val, val);
+			xfer->tx_buf = &rx_ring->uinc_irq_disable_buf;
+			xfer->len = len;
+		}
 	}
 }
 
···
 	 */
 	priv->regs_status.rxif = BIT(priv->rx[0]->fifo_nr);
 
-	netdev_dbg(priv->ndev,
-		   "FIFO setup: TEF:         0x%03x: %2d*%zu bytes = %4zu bytes\n",
-		   mcp251xfd_get_tef_obj_addr(0),
-		   priv->tx->obj_num, sizeof(struct mcp251xfd_hw_tef_obj),
-		   priv->tx->obj_num * sizeof(struct mcp251xfd_hw_tef_obj));
+	if (priv->tx_obj_num_coalesce_irq) {
+		netdev_dbg(priv->ndev,
+			   "FIFO setup: TEF:         0x%03x: %2d*%zu bytes = %4zu bytes (coalesce)\n",
+			   mcp251xfd_get_tef_obj_addr(0),
+			   priv->tx_obj_num_coalesce_irq,
+			   sizeof(struct mcp251xfd_hw_tef_obj),
+			   priv->tx_obj_num_coalesce_irq *
+			   sizeof(struct mcp251xfd_hw_tef_obj));
+
+		netdev_dbg(priv->ndev,
+			   "                         0x%03x: %2d*%zu bytes = %4zu bytes\n",
+			   mcp251xfd_get_tef_obj_addr(priv->tx_obj_num_coalesce_irq),
+			   priv->tx->obj_num - priv->tx_obj_num_coalesce_irq,
+			   sizeof(struct mcp251xfd_hw_tef_obj),
+			   (priv->tx->obj_num - priv->tx_obj_num_coalesce_irq) *
+			   sizeof(struct mcp251xfd_hw_tef_obj));
+	} else {
+		netdev_dbg(priv->ndev,
+			   "FIFO setup: TEF:         0x%03x: %2d*%zu bytes = %4zu bytes\n",
+			   mcp251xfd_get_tef_obj_addr(0),
+			   priv->tx->obj_num, sizeof(struct mcp251xfd_hw_tef_obj),
+			   priv->tx->obj_num * sizeof(struct mcp251xfd_hw_tef_obj));
+	}
 
 	mcp251xfd_for_each_rx_ring(priv, rx_ring, i) {
-		netdev_dbg(priv->ndev,
-			   "FIFO setup: RX-%u: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes\n",
-			   rx_ring->nr, rx_ring->fifo_nr,
-			   mcp251xfd_get_rx_obj_addr(rx_ring, 0),
-			   rx_ring->obj_num, rx_ring->obj_size,
-			   rx_ring->obj_num * rx_ring->obj_size);
+		if (rx_ring->nr == 0 && priv->rx_obj_num_coalesce_irq) {
+			netdev_dbg(priv->ndev,
+				   "FIFO setup: RX-%u: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes (coalesce)\n",
+				   rx_ring->nr, rx_ring->fifo_nr,
+				   mcp251xfd_get_rx_obj_addr(rx_ring, 0),
+				   priv->rx_obj_num_coalesce_irq, rx_ring->obj_size,
+				   priv->rx_obj_num_coalesce_irq * rx_ring->obj_size);
+
+			if (priv->rx_obj_num_coalesce_irq == MCP251XFD_FIFO_DEPTH)
+				continue;
+
+			netdev_dbg(priv->ndev,
+				   "                         0x%03x: %2u*%u bytes = %4u bytes\n",
+				   mcp251xfd_get_rx_obj_addr(rx_ring,
+							     priv->rx_obj_num_coalesce_irq),
+				   rx_ring->obj_num - priv->rx_obj_num_coalesce_irq,
+				   rx_ring->obj_size,
+				   (rx_ring->obj_num - priv->rx_obj_num_coalesce_irq) *
+				   rx_ring->obj_size);
+		} else {
+			netdev_dbg(priv->ndev,
+				   "FIFO setup: RX-%u: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes\n",
+				   rx_ring->nr, rx_ring->fifo_nr,
+				   mcp251xfd_get_rx_obj_addr(rx_ring, 0),
+				   rx_ring->obj_num, rx_ring->obj_size,
+				   rx_ring->obj_num * rx_ring->obj_size);
+		}
 	}
 
 	netdev_dbg(priv->ndev,
···
 		   priv->tx->obj_num * priv->tx->obj_size);
 
 	netdev_dbg(priv->ndev,
-		   "FIFO setup: free:                             %4u bytes\n",
+		   "FIFO setup: free:                             %4d bytes\n",
 		   MCP251XFD_RAM_SIZE - (base - MCP251XFD_RAM_START));
 
 	ram_used = base - MCP251XFD_RAM_START;
···
 	}
 }
 
+static enum hrtimer_restart mcp251xfd_rx_irq_timer(struct hrtimer *t)
+{
+	struct mcp251xfd_priv *priv = container_of(t, struct mcp251xfd_priv,
+						   rx_irq_timer);
+	struct mcp251xfd_rx_ring *ring = priv->rx[0];
+
+	if (test_bit(MCP251XFD_FLAGS_DOWN, priv->flags))
+		return HRTIMER_NORESTART;
+
+	spi_async(priv->spi, &ring->irq_enable_msg);
+
+	return HRTIMER_NORESTART;
+}
+
+static enum hrtimer_restart mcp251xfd_tx_irq_timer(struct hrtimer *t)
+{
+	struct mcp251xfd_priv *priv = container_of(t, struct mcp251xfd_priv,
+						   tx_irq_timer);
+	struct mcp251xfd_tef_ring *ring = priv->tef;
+
+	if (test_bit(MCP251XFD_FLAGS_DOWN, priv->flags))
+		return HRTIMER_NORESTART;
+
+	spi_async(priv->spi, &ring->irq_enable_msg);
+
+	return HRTIMER_NORESTART;
+}
+
+const struct can_ram_config mcp251xfd_ram_config = {
+	.rx = {
+		.size[CAN_RAM_MODE_CAN] = sizeof(struct mcp251xfd_hw_rx_obj_can),
+		.size[CAN_RAM_MODE_CANFD] = sizeof(struct mcp251xfd_hw_rx_obj_canfd),
+		.min = MCP251XFD_RX_OBJ_NUM_MIN,
+		.max = MCP251XFD_RX_OBJ_NUM_MAX,
+		.def[CAN_RAM_MODE_CAN] = CAN_RAM_NUM_MAX,
+		.def[CAN_RAM_MODE_CANFD] = CAN_RAM_NUM_MAX,
+		.fifo_num = MCP251XFD_FIFO_RX_NUM,
+		.fifo_depth_min = MCP251XFD_RX_FIFO_DEPTH_MIN,
+		.fifo_depth_coalesce_min = MCP251XFD_RX_FIFO_DEPTH_COALESCE_MIN,
+	},
+	.tx = {
+		.size[CAN_RAM_MODE_CAN] = sizeof(struct mcp251xfd_hw_tef_obj) +
+			sizeof(struct mcp251xfd_hw_tx_obj_can),
+		.size[CAN_RAM_MODE_CANFD] = sizeof(struct mcp251xfd_hw_tef_obj) +
+			sizeof(struct mcp251xfd_hw_tx_obj_canfd),
+		.min = MCP251XFD_TX_OBJ_NUM_MIN,
+		.max = MCP251XFD_TX_OBJ_NUM_MAX,
+		.def[CAN_RAM_MODE_CAN] = MCP251XFD_TX_OBJ_NUM_CAN_DEFAULT,
+		.def[CAN_RAM_MODE_CANFD] = MCP251XFD_TX_OBJ_NUM_CANFD_DEFAULT,
+		.fifo_num = MCP251XFD_FIFO_TX_NUM,
+		.fifo_depth_min = MCP251XFD_TX_FIFO_DEPTH_MIN,
+		.fifo_depth_coalesce_min = MCP251XFD_TX_FIFO_DEPTH_COALESCE_MIN,
+	},
+	.size = MCP251XFD_RAM_SIZE,
+	.fifo_depth = MCP251XFD_FIFO_DEPTH,
+};
+
 int mcp251xfd_ring_alloc(struct mcp251xfd_priv *priv)
 {
-	struct mcp251xfd_tx_ring *tx_ring;
+	const bool fd_mode = mcp251xfd_is_fd_mode(priv);
+	struct mcp251xfd_tx_ring *tx_ring = priv->tx;
 	struct mcp251xfd_rx_ring *rx_ring;
-	int tef_obj_size, tx_obj_size, rx_obj_size;
-	int tx_obj_num;
-	int ram_free, i;
+	u8 tx_obj_size, rx_obj_size;
+	u8 rem, i;
 
-	tef_obj_size = sizeof(struct mcp251xfd_hw_tef_obj);
-	if (mcp251xfd_is_fd_mode(priv)) {
-		tx_obj_num = MCP251XFD_TX_OBJ_NUM_CANFD;
-		tx_obj_size = sizeof(struct mcp251xfd_hw_tx_obj_canfd);
-		rx_obj_size = sizeof(struct mcp251xfd_hw_rx_obj_canfd);
-	} else {
-		tx_obj_num = MCP251XFD_TX_OBJ_NUM_CAN;
-		tx_obj_size = sizeof(struct mcp251xfd_hw_tx_obj_can);
-		rx_obj_size = sizeof(struct mcp251xfd_hw_rx_obj_can);
+	/* switching from CAN-2.0 to CAN-FD mode or vice versa */
+	if (fd_mode != test_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags)) {
+		struct can_ram_layout layout;
+
+		can_ram_get_layout(&layout, &mcp251xfd_ram_config, NULL, NULL, fd_mode);
+		priv->rx_obj_num = layout.default_rx;
+		tx_ring->obj_num = layout.default_tx;
 	}
 
-	tx_ring = priv->tx;
-	tx_ring->obj_num = tx_obj_num;
+	if (fd_mode) {
+		tx_obj_size = sizeof(struct mcp251xfd_hw_tx_obj_canfd);
+		rx_obj_size = sizeof(struct mcp251xfd_hw_rx_obj_canfd);
+		set_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags);
+	} else {
+		tx_obj_size = sizeof(struct mcp251xfd_hw_tx_obj_can);
+		rx_obj_size = sizeof(struct mcp251xfd_hw_rx_obj_can);
+		clear_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags);
+	}
+
 	tx_ring->obj_size = tx_obj_size;
 
-	ram_free = MCP251XFD_RAM_SIZE - tx_obj_num *
-		(tef_obj_size + tx_obj_size);
+	rem = priv->rx_obj_num;
+	for (i = 0; i < ARRAY_SIZE(priv->rx) && rem; i++) {
+		u8 rx_obj_num;
 
-	for (i = 0;
-	     i < ARRAY_SIZE(priv->rx) && ram_free >= rx_obj_size;
-	     i++) {
-		int rx_obj_num;
-
-		rx_obj_num = ram_free / rx_obj_size;
-		rx_obj_num = min(1 << (fls(rx_obj_num) - 1),
-				 MCP251XFD_RX_OBJ_NUM_MAX);
+		if (i == 0 && priv->rx_obj_num_coalesce_irq)
+			rx_obj_num = min_t(u8, priv->rx_obj_num_coalesce_irq * 2,
+					   MCP251XFD_FIFO_DEPTH);
+		else
+			rx_obj_num = min_t(u8, rounddown_pow_of_two(rem),
+					   MCP251XFD_FIFO_DEPTH);
+		rem -= rx_obj_num;
 
 		rx_ring = kzalloc(sizeof(*rx_ring) + rx_obj_size * rx_obj_num,
 				  GFP_KERNEL);
···
 			mcp251xfd_ring_free(priv);
 			return -ENOMEM;
 		}
+
 		rx_ring->obj_num = rx_obj_num;
 		rx_ring->obj_size = rx_obj_size;
 		priv->rx[i] = rx_ring;
-
-		ram_free -= rx_ring->obj_num * rx_ring->obj_size;
 	}
 	priv->rx_ring_num = i;
+
+	hrtimer_init(&priv->rx_irq_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	priv->rx_irq_timer.function = mcp251xfd_rx_irq_timer;
+
+	hrtimer_init(&priv->tx_irq_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	priv->tx_irq_timer.function = mcp251xfd_tx_irq_timer;
 
 	return 0;
 }

drivers/net/can/spi/mcp251xfd/mcp251xfd-rx.c

···
 	int err, n;
 
 	mcp251xfd_for_each_rx_ring(priv, ring, n) {
-		if (!(priv->regs_status.rxif & BIT(ring->fifo_nr)))
+		/* - if RX IRQ coalescing is active always handle ring 0
+		 * - only handle rings if RX IRQ is active
+		 */
+		if ((ring->nr > 0 || !priv->rx_obj_num_coalesce_irq) &&
+		    !(priv->regs_status.rxif & BIT(ring->fifo_nr)))
 			continue;
 
 		err = mcp251xfd_handle_rxif_ring(priv, ring);
 		if (err)
 			return err;
 	}
+
+	if (priv->rx_coalesce_usecs_irq)
+		hrtimer_start(&priv->rx_irq_timer,
+			      ns_to_ktime(priv->rx_coalesce_usecs_irq *
+					  NSEC_PER_USEC),
+			      HRTIMER_MODE_REL);
 
 	return 0;
 }

drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c

···
 		netif_wake_queue(priv->ndev);
 	}
 
+	if (priv->tx_coalesce_usecs_irq)
+		hrtimer_start(&priv->tx_irq_timer,
+			      ns_to_ktime(priv->tx_coalesce_usecs_irq *
+					  NSEC_PER_USEC),
+			      HRTIMER_MODE_REL);
+
 	return 0;
 }

drivers/net/can/spi/mcp251xfd/mcp251xfd.h

···
 #define MCP251XFD_REG_DEVID_ID_MASK GENMASK(7, 4)
 #define MCP251XFD_REG_DEVID_REV_MASK GENMASK(3, 0)
 
-/* number of TX FIFO objects, depending on CAN mode
- *
- * FIFO setup: tef: 8*12 bytes = 96 bytes, tx: 8*16 bytes = 128 bytes
- * FIFO setup: tef: 4*12 bytes = 48 bytes, tx: 4*72 bytes = 288 bytes
- */
-#define MCP251XFD_RX_OBJ_NUM_MAX 32
-#define MCP251XFD_TX_OBJ_NUM_CAN 8
-#define MCP251XFD_TX_OBJ_NUM_CANFD 4
-
-#if MCP251XFD_TX_OBJ_NUM_CAN > MCP251XFD_TX_OBJ_NUM_CANFD
-#define MCP251XFD_TX_OBJ_NUM_MAX MCP251XFD_TX_OBJ_NUM_CAN
-#else
-#define MCP251XFD_TX_OBJ_NUM_MAX MCP251XFD_TX_OBJ_NUM_CANFD
-#endif
-
-#define MCP251XFD_NAPI_WEIGHT 32
-
 /* SPI commands */
 #define MCP251XFD_SPI_INSTRUCTION_RESET 0x0000
 #define MCP251XFD_SPI_INSTRUCTION_WRITE 0x2000
···
 #define MCP251XFD_OSC_STAB_TIMEOUT_US (10 * MCP251XFD_OSC_STAB_SLEEP_US)
 #define MCP251XFD_POLL_SLEEP_US (10)
 #define MCP251XFD_POLL_TIMEOUT_US (USEC_PER_MSEC)
+
+/* Misc */
+#define MCP251XFD_NAPI_WEIGHT 32
 #define MCP251XFD_SOFTRESET_RETRIES_MAX 3
 #define MCP251XFD_READ_CRC_RETRIES_MAX 3
 #define MCP251XFD_ECC_CNT_MAX 2
···
 
 /* FIFO and Ring */
 #define MCP251XFD_FIFO_TEF_NUM 1U
-#define MCP251XFD_FIFO_RX_NUM_MAX 1U
+#define MCP251XFD_FIFO_RX_NUM 3U
 #define MCP251XFD_FIFO_TX_NUM 1U
+
+#define MCP251XFD_FIFO_DEPTH 32U
+
+#define MCP251XFD_RX_OBJ_NUM_MIN 16U
+#define MCP251XFD_RX_OBJ_NUM_MAX (MCP251XFD_FIFO_RX_NUM * MCP251XFD_FIFO_DEPTH)
+#define MCP251XFD_RX_FIFO_DEPTH_MIN 4U
+#define MCP251XFD_RX_FIFO_DEPTH_COALESCE_MIN 8U
+
+#define MCP251XFD_TX_OBJ_NUM_MIN 2U
+#define MCP251XFD_TX_OBJ_NUM_MAX 16U
+#define MCP251XFD_TX_OBJ_NUM_CAN_DEFAULT 8U
+#define MCP251XFD_TX_OBJ_NUM_CANFD_DEFAULT 4U
+#define MCP251XFD_TX_FIFO_DEPTH_MIN 2U
+#define MCP251XFD_TX_FIFO_DEPTH_COALESCE_MIN 2U
 
 static_assert(MCP251XFD_FIFO_TEF_NUM == 1U);
 static_assert(MCP251XFD_FIFO_TEF_NUM == MCP251XFD_FIFO_TX_NUM);
-static_assert(MCP251XFD_FIFO_RX_NUM_MAX <= 4U);
+static_assert(MCP251XFD_FIFO_RX_NUM <= 4U);
 
 /* Silence TX MAB overflow warnings */
 #define MCP251XFD_QUIRK_MAB_NO_WARN BIT(0)
···
 	/* u8 obj_num equals tx_ring->obj_num */
 	/* u8 obj_size equals sizeof(struct mcp251xfd_hw_tef_obj) */
 
+	union mcp251xfd_write_reg_buf irq_enable_buf;
+	struct spi_transfer irq_enable_xfer;
+	struct spi_message irq_enable_msg;
+
 	union mcp251xfd_write_reg_buf uinc_buf;
+	union mcp251xfd_write_reg_buf uinc_irq_disable_buf;
 	struct spi_transfer uinc_xfer[MCP251XFD_TX_OBJ_NUM_MAX];
 };
 
···
 	u8 obj_num;
 	u8 obj_size;
 
+	union mcp251xfd_write_reg_buf irq_enable_buf;
+	struct spi_transfer irq_enable_xfer;
+	struct spi_message irq_enable_msg;
+
 	union mcp251xfd_write_reg_buf uinc_buf;
-	struct spi_transfer uinc_xfer[MCP251XFD_RX_OBJ_NUM_MAX];
+	union mcp251xfd_write_reg_buf uinc_irq_disable_buf;
+	struct spi_transfer uinc_xfer[MCP251XFD_FIFO_DEPTH];
 	struct mcp251xfd_hw_rx_obj_canfd obj[];
 };
 
···
 	u32 quirks;
 };
 
+enum mcp251xfd_flags {
+	MCP251XFD_FLAGS_DOWN,
+	MCP251XFD_FLAGS_FD_MODE,
+
+	__MCP251XFD_FLAGS_SIZE__
+};
+
 struct mcp251xfd_priv {
 	struct can_priv can;
 	struct can_rx_offload offload;
···
 	u32 spi_max_speed_hz_slow;
 
 	struct mcp251xfd_tef_ring tef[MCP251XFD_FIFO_TEF_NUM];
-	struct mcp251xfd_rx_ring *rx[MCP251XFD_FIFO_RX_NUM_MAX];
+	struct mcp251xfd_rx_ring *rx[MCP251XFD_FIFO_RX_NUM];
 	struct mcp251xfd_tx_ring tx[MCP251XFD_FIFO_TX_NUM];
 
+	DECLARE_BITMAP(flags, __MCP251XFD_FLAGS_SIZE__);
+
 	u8 rx_ring_num;
+	u8 rx_obj_num;
+	u8 rx_obj_num_coalesce_irq;
+	u8 tx_obj_num_coalesce_irq;
+
+	u32 rx_coalesce_usecs_irq;
+	u32 tx_coalesce_usecs_irq;
+	struct hrtimer rx_irq_timer;
+	struct hrtimer tx_irq_timer;
 
 	struct mcp251xfd_ecc ecc;
 	struct mcp251xfd_regs_status regs_status;
···
 u16 mcp251xfd_crc16_compute2(const void *cmd, size_t cmd_size,
 			     const void *data, size_t data_size);
 u16 mcp251xfd_crc16_compute(const void *data, size_t data_size);
+void mcp251xfd_ethtool_init(struct mcp251xfd_priv *priv);
 int mcp251xfd_regmap_init(struct mcp251xfd_priv *priv);
+extern const struct can_ram_config mcp251xfd_ram_config;
 int mcp251xfd_ring_init(struct mcp251xfd_priv *priv);
 void mcp251xfd_ring_free(struct mcp251xfd_priv *priv);
 int mcp251xfd_ring_alloc(struct mcp251xfd_priv *priv);

drivers/net/can/vxcan.c

···
 	if (skb) {
 		consume_skb(oskb);
 	} else {
-		kfree(oskb);
+		kfree_skb(oskb);
 		goto out_unlock;
 	}