diff mbox series

[v8,2/2] can: esd: add support for esd GmbH PCIe/402 CAN interface family

Message ID 20231025141635.1459606-3-stefan.maetje@esd.eu (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series can: esd: add support for esd GmbH PCIe/402 CAN interface | expand

Checks

Context Check Description
netdev/tree_selection success Series ignored based on subject, async

Commit Message

Stefan Mätje Oct. 25, 2023, 2:16 p.m. UTC
This patch adds support for the PCI based PCIe/402 CAN interface family
from esd GmbH that is available with various form factors
(https://esd.eu/en/products/402-series-can-interfaces).

All boards utilize a FPGA based CAN controller solution developed
by esd (esdACC). For more information on the esdACC see
https://esd.eu/en/products/esdacc.

This driver detects all available CAN interface board variants of
the family but atm. operates the CAN-FD capable devices in
Classic-CAN mode only! A later patch will introduce the CAN-FD
functionality in this driver.

Co-developed-by: Thomas Körper <thomas.koerper@esd.eu>
Signed-off-by: Thomas Körper <thomas.koerper@esd.eu>
Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
---
 drivers/net/can/Kconfig                |   1 +
 drivers/net/can/Makefile               |   1 +
 drivers/net/can/esd/Kconfig            |  12 +
 drivers/net/can/esd/Makefile           |   7 +
 drivers/net/can/esd/esd_402_pci-core.c | 510 ++++++++++++++++
 drivers/net/can/esd/esdacc.c           | 771 +++++++++++++++++++++++++
 drivers/net/can/esd/esdacc.h           | 393 +++++++++++++
 7 files changed, 1695 insertions(+)
 create mode 100644 drivers/net/can/esd/Kconfig
 create mode 100644 drivers/net/can/esd/Makefile
 create mode 100644 drivers/net/can/esd/esd_402_pci-core.c
 create mode 100644 drivers/net/can/esd/esdacc.c
 create mode 100644 drivers/net/can/esd/esdacc.h

Comments

Simon Horman Nov. 3, 2023, 4:48 p.m. UTC | #1
On Wed, Oct 25, 2023 at 04:16:35PM +0200, Stefan Mätje wrote:
> This patch adds support for the PCI based PCIe/402 CAN interface family
> from esd GmbH that is available with various form factors
> (https://esd.eu/en/products/402-series-can-interfaces).
> 
> All boards utilize a FPGA based CAN controller solution developed
> by esd (esdACC). For more information on the esdACC see
> https://esd.eu/en/products/esdacc.
> 
> This driver detects all available CAN interface board variants of
> the family but atm. operates the CAN-FD capable devices in
> Classic-CAN mode only! A later patch will introduce the CAN-FD
> functionality in this driver.
> 
> Co-developed-by: Thomas Körper <thomas.koerper@esd.eu>
> Signed-off-by: Thomas Körper <thomas.koerper@esd.eu>
> Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>

...

> +static int pci402_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> +{
> +	struct pci402_card *card = NULL;
> +	int err;
> +
> +	err = pci_enable_device(pdev);
> +	if (err)
> +		return err;
> +
> +	card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
> +	if (!card)

Hi Thomas and Stefan,

If this condition is met then the function will return err,
but err is set to 0. Perhaps it should be set to an error value here?

Flagged by Smatch.

> +		goto failure_disable_pci;
> +
> +	pci_set_drvdata(pdev, card);
> +
> +	err = pci_request_regions(pdev, pci_name(pdev));
> +	if (err)
> +		goto failure_disable_pci;
> +
> +	card->addr = pci_iomap(pdev, PCI402_BAR, PCI402_IO_LEN_TOTAL);
> +	if (!card->addr) {
> +		err = -ENOMEM;
> +		goto failure_release_regions;
> +	}
> +
> +	err = pci402_init_card(pdev);
> +	if (err)
> +		goto failure_unmap;
> +
> +	err = pci402_init_dma(pdev);
> +	if (err)
> +		goto failure_unmap;
> +
> +	err = pci402_init_interrupt(pdev);
> +	if (err)
> +		goto failure_finish_dma;
> +
> +	err = pci402_init_cores(pdev);
> +	if (err)
> +		goto failure_finish_interrupt;
> +
> +	return 0;
> +
> +failure_finish_interrupt:
> +	pci402_finish_interrupt(pdev);
> +
> +failure_finish_dma:
> +	pci402_finish_dma(pdev);
> +
> +failure_unmap:
> +	pci_iounmap(pdev, card->addr);
> +
> +failure_release_regions:
> +	pci_release_regions(pdev);
> +
> +failure_disable_pci:
> +	pci_disable_device(pdev);
> +
> +	return err;
> +}

...
Stefan Mätje Nov. 7, 2023, 1:27 p.m. UTC | #2
Am Freitag, dem 03.11.2023 um 16:48 +0000 schrieb Simon Horman:
> On Wed, Oct 25, 2023 at 04:16:35PM +0200, Stefan Mätje wrote:
> > This patch adds support for the PCI based PCIe/402 CAN interface family
> > from esd GmbH that is available with various form factors
> > (https://esd.eu/en/products/402-series-can-interfaces).
> > 
> > All boards utilize a FPGA based CAN controller solution developed
> > by esd (esdACC). For more information on the esdACC see
> > https://esd.eu/en/products/esdacc.
> > 
> > This driver detects all available CAN interface board variants of
> > the family but atm. operates the CAN-FD capable devices in
> > Classic-CAN mode only! A later patch will introduce the CAN-FD
> > functionality in this driver.
> > 
> > Co-developed-by: Thomas Körper <thomas.koerper@esd.eu>
> > Signed-off-by: Thomas Körper <thomas.koerper@esd.eu>
> > Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
> 
> ...
> 
> > +static int pci402_probe(struct pci_dev *pdev, const struct pci_device_id
> > *ent)
> > +{
> > +       struct pci402_card *card = NULL;
> > +       int err;
> > +
> > +       err = pci_enable_device(pdev);
> > +       if (err)
> > +               return err;
> > +
> > +       card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
> > +       if (!card)
> 
> Hi Thomas and Stefan,
> 
> If this condition is met then the function will return err,
> but err is set to 0. Perhaps it should be set to an error value here?
> 
> Flagged by Smatch.

Hi Simon,

thank you for reviewing this. Looking at the code it is apparently wrong.

I was not aware of smatch. I got a copy and could reproduce the error report.
This will add another tool of static code analysis to my release routine.

An upgraded patch with a fix will follow.

Best regards,
    Stefan

> > +               goto failure_disable_pci;
> > +
> > +       pci_set_drvdata(pdev, card);
> > +
> > +       err = pci_request_regions(pdev, pci_name(pdev));
> > +       if (err)
> > +               goto failure_disable_pci;
> > +
> > +       card->addr = pci_iomap(pdev, PCI402_BAR, PCI402_IO_LEN_TOTAL);
> > +       if (!card->addr) {
> > +               err = -ENOMEM;
> > +               goto failure_release_regions;
> > +       }
> > +
> > +       err = pci402_init_card(pdev);
> > +       if (err)
> > +               goto failure_unmap;
> > +
> > +       err = pci402_init_dma(pdev);
> > +       if (err)
> > +               goto failure_unmap;
> > +
> > +       err = pci402_init_interrupt(pdev);
> > +       if (err)
> > +               goto failure_finish_dma;
> > +
> > +       err = pci402_init_cores(pdev);
> > +       if (err)
> > +               goto failure_finish_interrupt;
> > +
> > +       return 0;
> > +
> > +failure_finish_interrupt:
> > +       pci402_finish_interrupt(pdev);
> > +
> > +failure_finish_dma:
> > +       pci402_finish_dma(pdev);
> > +
> > +failure_unmap:
> > +       pci_iounmap(pdev, card->addr);
> > +
> > +failure_release_regions:
> > +       pci_release_regions(pdev);
> > +
> > +failure_disable_pci:
> > +       pci_disable_device(pdev);
> > +
> > +       return err;
> > +}
> 
> ...
Simon Horman Nov. 8, 2023, 3:23 p.m. UTC | #3
On Tue, Nov 07, 2023 at 01:27:34PM +0000, Stefan Mätje wrote:
> Am Freitag, dem 03.11.2023 um 16:48 +0000 schrieb Simon Horman:
> > On Wed, Oct 25, 2023 at 04:16:35PM +0200, Stefan Mätje wrote:
> > > This patch adds support for the PCI based PCIe/402 CAN interface family
> > > from esd GmbH that is available with various form factors
> > > (https://esd.eu/en/products/402-series-can-interfaces).
> > > 
> > > All boards utilize a FPGA based CAN controller solution developed
> > > by esd (esdACC). For more information on the esdACC see
> > > https://esd.eu/en/products/esdacc.
> > > 
> > > This driver detects all available CAN interface board variants of
> > > the family but atm. operates the CAN-FD capable devices in
> > > Classic-CAN mode only! A later patch will introduce the CAN-FD
> > > functionality in this driver.
> > > 
> > > Co-developed-by: Thomas Körper <thomas.koerper@esd.eu>
> > > Signed-off-by: Thomas Körper <thomas.koerper@esd.eu>
> > > Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
> > 
> > ...
> > 
> > > +static int pci402_probe(struct pci_dev *pdev, const struct pci_device_id
> > > *ent)
> > > +{
> > > +       struct pci402_card *card = NULL;
> > > +       int err;
> > > +
> > > +       err = pci_enable_device(pdev);
> > > +       if (err)
> > > +               return err;
> > > +
> > > +       card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
> > > +       if (!card)
> > 
> > Hi Thomas and Stefan,
> > 
> > If this condition is met then the function will return err,
> > but err is set to 0. Perhaps it should be set to an error value here?
> > 
> > Flagged by Smatch.
> 
> Hi Simon,
> 
> thank you for reviewing this. Looking at the code it is apparently wrong.
> 
> I was not aware of smatch. I got a copy and could reproduce the error report.
> This will add another tool of static code analysis to my release routine.
> 
> An upgraded patch with a fix will follow.

Thanks Stefan, that sounds good to me on both counts.

...
diff mbox series

Patch

diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index 649453a3c858..b9a65b44ccef 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -217,6 +217,7 @@  config CAN_XILINXCAN
 source "drivers/net/can/c_can/Kconfig"
 source "drivers/net/can/cc770/Kconfig"
 source "drivers/net/can/ctucanfd/Kconfig"
+source "drivers/net/can/esd/Kconfig"
 source "drivers/net/can/ifi_canfd/Kconfig"
 source "drivers/net/can/m_can/Kconfig"
 source "drivers/net/can/mscan/Kconfig"
diff --git a/drivers/net/can/Makefile b/drivers/net/can/Makefile
index ff8f76295d13..4669cd51e7bf 100644
--- a/drivers/net/can/Makefile
+++ b/drivers/net/can/Makefile
@@ -8,6 +8,7 @@  obj-$(CONFIG_CAN_VXCAN)		+= vxcan.o
 obj-$(CONFIG_CAN_SLCAN)		+= slcan/
 
 obj-y				+= dev/
+obj-y				+= esd/
 obj-y				+= rcar/
 obj-y				+= spi/
 obj-y				+= usb/
diff --git a/drivers/net/can/esd/Kconfig b/drivers/net/can/esd/Kconfig
new file mode 100644
index 000000000000..54bfc366634c
--- /dev/null
+++ b/drivers/net/can/esd/Kconfig
@@ -0,0 +1,12 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+config CAN_ESD_402_PCI
+	tristate "esd electronics gmbh CAN-PCI(e)/402 family"
+	depends on PCI && HAS_DMA
+	help
+	  Support for C402 card family from esd electronics gmbh.
+	  This card family is based on the ESDACC CAN controller and
+	  available in several form factors:  PCI, PCIe, PCIe Mini,
+	  M.2 PCIe, CPCIserial, PMC, XMC  (see https://esd.eu/en)
+
+	  This driver can also be built as a module. In this case the
+	  module will be called esd_402_pci.
diff --git a/drivers/net/can/esd/Makefile b/drivers/net/can/esd/Makefile
new file mode 100644
index 000000000000..5dd2d470c286
--- /dev/null
+++ b/drivers/net/can/esd/Makefile
@@ -0,0 +1,7 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+#
+#  Makefile for esd gmbh ESDACC controller driver
+#
+esd_402_pci-objs := esdacc.o esd_402_pci-core.o
+
+obj-$(CONFIG_CAN_ESD_402_PCI) += esd_402_pci.o
diff --git a/drivers/net/can/esd/esd_402_pci-core.c b/drivers/net/can/esd/esd_402_pci-core.c
new file mode 100644
index 000000000000..84be508c6344
--- /dev/null
+++ b/drivers/net/can/esd/esd_402_pci-core.c
@@ -0,0 +1,510 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2015 - 2016 Thomas Körper, esd electronic system design gmbh
+ * Copyright (C) 2017 - 2022 Stefan Mätje, esd electronics gmbh
+ */
+
+#include <linux/can/dev.h>
+#include <linux/can.h>
+#include <linux/can/netlink.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/pci.h>
+
+#include "esdacc.h"
+
+#define ESD_PCI_DEVICE_ID_PCIE402 0x0402
+
+#define PCI402_FPGA_VER_MIN 0x003d
+#define PCI402_MAX_CORES 6
+#define PCI402_BAR 0
+#define PCI402_IO_OV_OFFS 0
+#define PCI402_IO_PCIEP_OFFS 0x10000
+#define PCI402_IO_LEN_TOTAL 0x20000
+#define PCI402_IO_LEN_CORE 0x2000
+#define PCI402_PCICFG_MSICAP 0x50
+
+#define PCI402_DMA_MASK DMA_BIT_MASK(32)
+#define PCI402_DMA_SIZE ALIGN(0x10000, PAGE_SIZE)
+
+#define PCI402_PCIEP_OF_INT_ENABLE 0x0050
+#define PCI402_PCIEP_OF_BM_ADDR_LO 0x1000
+#define PCI402_PCIEP_OF_BM_ADDR_HI 0x1004
+#define PCI402_PCIEP_OF_MSI_ADDR_LO 0x1008
+#define PCI402_PCIEP_OF_MSI_ADDR_HI 0x100c
+
+/* The BTR register capabilities described by the can_bittiming_const structures
+ * below are valid since ESDACC version 0x0032.
+ */
+
+/* Used if the ESDACC FPGA is built as CAN-Classic version. */
+static const struct can_bittiming_const pci402_bittiming_const = {
+	.name = "esd_402",
+	.tseg1_min = 1,
+	.tseg1_max = 16,
+	.tseg2_min = 1,
+	.tseg2_max = 8,
+	.sjw_max = 4,
+	.brp_min = 1,
+	.brp_max = 512,
+	.brp_inc = 1,
+};
+
+/* Used if the ESDACC FPGA is built as CAN-FD version. */
+static const struct can_bittiming_const pci402_bittiming_const_canfd = {
+	.name = "esd_402fd",
+	.tseg1_min = 1,
+	.tseg1_max = 256,
+	.tseg2_min = 1,
+	.tseg2_max = 128,
+	.sjw_max = 128,
+	.brp_min = 1,
+	.brp_max = 256,
+	.brp_inc = 1,
+};
+
+static const struct net_device_ops pci402_acc_netdev_ops = {
+	.ndo_open = acc_open,
+	.ndo_stop = acc_close,
+	.ndo_start_xmit = acc_start_xmit,
+	.ndo_change_mtu = can_change_mtu
+};
+
+struct pci402_card {
+	/* Actually mapped io space, all other iomem derived from this */
+	void __iomem *addr;
+	void __iomem *addr_pciep;
+
+	void *dma_buf;
+	dma_addr_t dma_hnd;
+
+	struct acc_ov ov;
+	struct acc_core *cores;
+
+	bool msi_enabled;
+};
+
+static irqreturn_t pci402_interrupt(int irq, void *dev_id)
+{
+	struct pci_dev *pdev = dev_id;
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	irqreturn_t irq_status;
+
+	irq_status = acc_card_interrupt(&card->ov, card->cores);
+
+	return irq_status;
+}
+
+static int pci402_set_msiconfig(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	u32 addr_lo_offs = 0;
+	u32 addr_lo = 0;
+	u32 addr_hi = 0;
+	u32 data = 0;
+	u16 csr = 0;
+	int err;
+
+	/* The FPGA hard IP PCIe core implements a 64-bit MSI Capability
+	 * Register Format
+	 */
+	err = pci_read_config_word(pdev, PCI402_PCICFG_MSICAP + PCI_MSI_FLAGS, &csr);
+	if (err)
+		goto failed;
+
+	err = pci_read_config_dword(pdev, PCI402_PCICFG_MSICAP + PCI_MSI_ADDRESS_LO,
+				    &addr_lo);
+	if (err)
+		goto failed;
+	err = pci_read_config_dword(pdev, PCI402_PCICFG_MSICAP + PCI_MSI_ADDRESS_HI,
+				    &addr_hi);
+	if (err)
+		goto failed;
+
+	err = pci_read_config_dword(pdev, PCI402_PCICFG_MSICAP + PCI_MSI_DATA_64,
+				    &data);
+	if (err)
+		goto failed;
+
+	addr_lo_offs = addr_lo & 0x0000ffff;
+	addr_lo &= 0xffff0000;
+
+	if (addr_hi)
+		addr_lo |= 1; /* To enable 64-Bit addressing in PCIe endpoint */
+
+	if (!(csr & PCI_MSI_FLAGS_ENABLE)) {
+		err = -EINVAL;
+		goto failed;
+	}
+
+	iowrite32(addr_lo, card->addr_pciep + PCI402_PCIEP_OF_MSI_ADDR_LO);
+	iowrite32(addr_hi, card->addr_pciep + PCI402_PCIEP_OF_MSI_ADDR_HI);
+	acc_ov_write32(&card->ov, ACC_OV_OF_MSI_ADDRESSOFFSET, addr_lo_offs);
+	acc_ov_write32(&card->ov, ACC_OV_OF_MSI_DATA, data);
+
+	return 0;
+
+failed:
+	pci_warn(pdev, "Error while setting MSI configuration:\n"
+		 "CSR: 0x%.4x, addr: 0x%.8x%.8x, offs: 0x%.4x, data: 0x%.8x\n",
+		 csr, addr_hi, addr_lo, addr_lo_offs, data);
+
+	return err;
+}
+
+static int pci402_init_card(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+
+	card->ov.addr = card->addr + PCI402_IO_OV_OFFS;
+	card->addr_pciep = card->addr + PCI402_IO_PCIEP_OFFS;
+
+	acc_reset_fpga(&card->ov);
+	acc_init_ov(&card->ov, &pdev->dev);
+
+	if (card->ov.version < PCI402_FPGA_VER_MIN) {
+		pci_err(pdev,
+			"ESDACC version (0x%.4x) outdated, please update\n",
+			card->ov.version);
+		return -EINVAL;
+	}
+
+	if (card->ov.timestamp_frequency != ACC_TS_FREQ_80MHZ) {
+		pci_err(pdev,
+			"esdACC timestamp frequency of %uHz not supported by driver. Aborted.\n",
+			card->ov.timestamp_frequency);
+		return -EINVAL;
+	}
+
+	if (card->ov.active_cores > PCI402_MAX_CORES) {
+		pci_err(pdev,
+			"Card has more active cores (%u) than supported by driver. Aborted.\n",
+			card->ov.active_cores);
+		return -EINVAL;
+	}
+	card->cores = devm_kcalloc(&pdev->dev, card->ov.active_cores,
+				   sizeof(struct acc_core), GFP_KERNEL);
+	if (!card->cores)
+		return -ENOMEM;
+
+	if (card->ov.features & ACC_OV_REG_FEAT_MASK_CANFD) {
+		pci_warn(pdev,
+			 "ESDACC with CAN-FD feature detected. This driver doesn't support CAN-FD yet.\n");
+	}
+
+#ifdef __LITTLE_ENDIAN
+	/* So card converts all busmastered data to LE for us: */
+	acc_ov_set_bits(&card->ov, ACC_OV_OF_MODE,
+			ACC_OV_REG_MODE_MASK_ENDIAN_LITTLE);
+#endif
+
+	return 0;
+}
+
+static int pci402_init_interrupt(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int err;
+
+	err = pci_enable_msi(pdev);
+	if (!err) {
+		err = pci402_set_msiconfig(pdev);
+		if (!err) {
+			card->msi_enabled = true;
+			acc_ov_set_bits(&card->ov, ACC_OV_OF_MODE,
+					ACC_OV_REG_MODE_MASK_MSI_ENABLE);
+			pci_info(pdev, "MSI enabled\n");
+		}
+	}
+
+	err = devm_request_irq(&pdev->dev, pdev->irq, pci402_interrupt,
+			       IRQF_SHARED, dev_name(&pdev->dev), pdev);
+	if (err)
+		goto failure_msidis;
+
+	iowrite32(1, card->addr_pciep + PCI402_PCIEP_OF_INT_ENABLE);
+
+	return 0;
+
+failure_msidis:
+	if (card->msi_enabled) {
+		acc_ov_clear_bits(&card->ov, ACC_OV_OF_MODE,
+				  ACC_OV_REG_MODE_MASK_MSI_ENABLE);
+		pci_disable_msi(pdev);
+		card->msi_enabled = false;
+	}
+
+	return err;
+}
+
+static void pci402_finish_interrupt(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+
+	iowrite32(0, card->addr_pciep + PCI402_PCIEP_OF_INT_ENABLE);
+	devm_free_irq(&pdev->dev, pdev->irq, pdev);
+
+	if (card->msi_enabled) {
+		acc_ov_clear_bits(&card->ov, ACC_OV_OF_MODE,
+				  ACC_OV_REG_MODE_MASK_MSI_ENABLE);
+		pci_disable_msi(pdev);
+		card->msi_enabled = false;
+	}
+}
+
+static int pci402_init_dma(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int err;
+
+	err = dma_set_coherent_mask(&pdev->dev, PCI402_DMA_MASK);
+	if (err) {
+		pci_err(pdev, "DMA set mask failed!\n");
+		return err;
+	}
+
+	/* The ESDACC DMA engine needs the DMA buffer aligned to a 64k
+	 * boundary. The DMA API guarantees to align the returned buffer to the
+	 * smallest PAGE_SIZE order which is greater than or equal to the
+	 * requested size. With PCI402_DMA_SIZE == 64kB this suffices here.
+	 */
+	card->dma_buf = dma_alloc_coherent(&pdev->dev, PCI402_DMA_SIZE,
+					   &card->dma_hnd, GFP_KERNEL);
+	if (!card->dma_buf)
+		return -ENOMEM;
+
+	acc_init_bm_ptr(&card->ov, card->cores, card->dma_buf);
+
+	iowrite32(card->dma_hnd,
+		  card->addr_pciep + PCI402_PCIEP_OF_BM_ADDR_LO);
+	iowrite32(0, card->addr_pciep + PCI402_PCIEP_OF_BM_ADDR_HI);
+
+	pci_set_master(pdev);
+
+	acc_ov_set_bits(&card->ov, ACC_OV_OF_MODE,
+			ACC_OV_REG_MODE_MASK_BM_ENABLE);
+
+	return 0;
+}
+
+static void pci402_finish_dma(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int i;
+
+	acc_ov_clear_bits(&card->ov, ACC_OV_OF_MODE,
+			  ACC_OV_REG_MODE_MASK_BM_ENABLE);
+
+	pci_clear_master(pdev);
+
+	iowrite32(0, card->addr_pciep + PCI402_PCIEP_OF_BM_ADDR_LO);
+	iowrite32(0, card->addr_pciep + PCI402_PCIEP_OF_BM_ADDR_HI);
+
+	card->ov.bmfifo.messages = NULL;
+	card->ov.bmfifo.irq_cnt = NULL;
+	for (i = 0; i < card->ov.active_cores; i++) {
+		struct acc_core *core = &card->cores[i];
+
+		core->bmfifo.messages = NULL;
+		core->bmfifo.irq_cnt = NULL;
+	}
+
+	dma_free_coherent(&pdev->dev, PCI402_DMA_SIZE, card->dma_buf,
+			  card->dma_hnd);
+	card->dma_buf = NULL;
+}
+
+static int pci402_init_cores(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int err;
+	int i;
+
+	for (i = 0; i < card->ov.active_cores; i++) {
+		struct acc_core *core = &card->cores[i];
+		struct acc_net_priv *priv;
+		struct net_device *netdev;
+		u32 fifo_config;
+
+		core->addr = card->ov.addr + (i + 1) * PCI402_IO_LEN_CORE;
+
+		fifo_config = acc_read32(core, ACC_CORE_OF_TXFIFO_CONFIG);
+		core->tx_fifo_size = (fifo_config >> 24);
+		if (core->tx_fifo_size <= 1) {
+			pci_err(pdev, "Invalid tx_fifo_size!\n");
+			err = -EINVAL;
+			goto failure;
+		}
+
+		netdev = alloc_candev(sizeof(*priv), core->tx_fifo_size);
+		if (!netdev) {
+			err = -ENOMEM;
+			goto failure;
+		}
+		core->netdev = netdev;
+
+		netdev->flags |= IFF_ECHO;
+		netdev->dev_port = i;
+		netdev->netdev_ops = &pci402_acc_netdev_ops;
+		SET_NETDEV_DEV(netdev, &pdev->dev);
+
+		priv = netdev_priv(netdev);
+		priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
+			CAN_CTRLMODE_LISTENONLY |
+			CAN_CTRLMODE_BERR_REPORTING |
+			CAN_CTRLMODE_CC_LEN8_DLC;
+
+		priv->can.clock.freq = card->ov.core_frequency;
+		if (card->ov.features & ACC_OV_REG_FEAT_MASK_CANFD)
+			priv->can.bittiming_const = &pci402_bittiming_const_canfd;
+		else
+			priv->can.bittiming_const = &pci402_bittiming_const;
+		priv->can.do_set_bittiming = acc_set_bittiming;
+		priv->can.do_set_mode = acc_set_mode;
+		priv->can.do_get_berr_counter = acc_get_berr_counter;
+
+		priv->core = core;
+		priv->ov = &card->ov;
+
+		err = register_candev(netdev);
+		if (err) {
+			free_candev(core->netdev);
+			core->netdev = NULL;
+			goto failure;
+		}
+
+		netdev_info(netdev, "registered\n");
+	}
+
+	return 0;
+
+failure:
+	for (i--; i >= 0; i--) {
+		struct acc_core *core = &card->cores[i];
+
+		netdev_info(core->netdev, "unregistering...\n");
+		unregister_candev(core->netdev);
+
+		free_candev(core->netdev);
+		core->netdev = NULL;
+	}
+
+	return err;
+}
+
+static void pci402_finish_cores(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < card->ov.active_cores; i++) {
+		struct acc_core *core = &card->cores[i];
+
+		netdev_info(core->netdev, "unregister\n");
+		unregister_candev(core->netdev);
+
+		free_candev(core->netdev);
+		core->netdev = NULL;
+	}
+}
+
+static int pci402_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+	struct pci402_card *card = NULL;
+	int err;
+
+	err = pci_enable_device(pdev);
+	if (err)
+		return err;
+
+	card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
+	if (!card)
+		goto failure_disable_pci;
+
+	pci_set_drvdata(pdev, card);
+
+	err = pci_request_regions(pdev, pci_name(pdev));
+	if (err)
+		goto failure_disable_pci;
+
+	card->addr = pci_iomap(pdev, PCI402_BAR, PCI402_IO_LEN_TOTAL);
+	if (!card->addr) {
+		err = -ENOMEM;
+		goto failure_release_regions;
+	}
+
+	err = pci402_init_card(pdev);
+	if (err)
+		goto failure_unmap;
+
+	err = pci402_init_dma(pdev);
+	if (err)
+		goto failure_unmap;
+
+	err = pci402_init_interrupt(pdev);
+	if (err)
+		goto failure_finish_dma;
+
+	err = pci402_init_cores(pdev);
+	if (err)
+		goto failure_finish_interrupt;
+
+	return 0;
+
+failure_finish_interrupt:
+	pci402_finish_interrupt(pdev);
+
+failure_finish_dma:
+	pci402_finish_dma(pdev);
+
+failure_unmap:
+	pci_iounmap(pdev, card->addr);
+
+failure_release_regions:
+	pci_release_regions(pdev);
+
+failure_disable_pci:
+	pci_disable_device(pdev);
+
+	return err;
+}
+
+static void pci402_remove(struct pci_dev *pdev)
+{
+	struct pci402_card *card = pci_get_drvdata(pdev);
+
+	pci402_finish_interrupt(pdev);
+	pci402_finish_cores(pdev);
+	pci402_finish_dma(pdev);
+	pci_iounmap(pdev, card->addr);
+	pci_release_regions(pdev);
+	pci_disable_device(pdev);
+}
+
+static const struct pci_device_id pci402_tbl[] = {
+	{
+		.vendor = PCI_VENDOR_ID_ESDGMBH,
+		.device = ESD_PCI_DEVICE_ID_PCIE402,
+		.subvendor = PCI_VENDOR_ID_ESDGMBH,
+		.subdevice = PCI_ANY_ID,
+	},
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, pci402_tbl);
+
+static struct pci_driver pci402_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = pci402_tbl,
+	.probe = pci402_probe,
+	.remove = pci402_remove,
+};
+module_pci_driver(pci402_driver);
+
+MODULE_DESCRIPTION("Socket-CAN driver for esd CAN 402 card family with esdACC core on PCIe");
+MODULE_AUTHOR("Thomas Körper <socketcan@esd.eu>");
+MODULE_AUTHOR("Stefan Mätje <stefan.maetje@esd.eu>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/can/esd/esdacc.c b/drivers/net/can/esd/esdacc.c
new file mode 100644
index 000000000000..49017c986c70
--- /dev/null
+++ b/drivers/net/can/esd/esdacc.c
@@ -0,0 +1,771 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2015 - 2016 Thomas Körper, esd electronic system design gmbh
+ * Copyright (C) 2017 - 2022 Stefan Mätje, esd electronics gmbh
+ */
+
+#include "esdacc.h"
+
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/ktime.h>
+
+/* ecc value of esdACC equals SJA1000's ECC register */
+#define ACC_ECC_SEG			0x1f
+#define ACC_ECC_DIR			0x20
+#define ACC_ECC_BIT			0x00
+#define ACC_ECC_FORM			0x40
+#define ACC_ECC_STUFF			0x80
+#define ACC_ECC_MASK			0xc0
+
+#define ACC_BM_IRQ_UNMASK_ALL		0x55555555U
+#define ACC_BM_IRQ_MASK_ALL		0xaaaaaaaaU
+#define ACC_BM_IRQ_MASK			0x2U
+#define ACC_BM_IRQ_UNMASK		0x1U
+#define ACC_BM_LENFLAG_TX		0x20
+
+#define ACC_REG_STATUS_IDX_STATUS_DOS	16
+#define ACC_REG_STATUS_IDX_STATUS_ES	17
+#define ACC_REG_STATUS_IDX_STATUS_EP	18
+#define ACC_REG_STATUS_IDX_STATUS_BS	19
+#define ACC_REG_STATUS_IDX_STATUS_RBS	20
+#define ACC_REG_STATUS_IDX_STATUS_RS	21
+#define ACC_REG_STATUS_MASK_STATUS_DOS	BIT(ACC_REG_STATUS_IDX_STATUS_DOS)
+#define ACC_REG_STATUS_MASK_STATUS_ES	BIT(ACC_REG_STATUS_IDX_STATUS_ES)
+#define ACC_REG_STATUS_MASK_STATUS_EP	BIT(ACC_REG_STATUS_IDX_STATUS_EP)
+#define ACC_REG_STATUS_MASK_STATUS_BS	BIT(ACC_REG_STATUS_IDX_STATUS_BS)
+#define ACC_REG_STATUS_MASK_STATUS_RBS	BIT(ACC_REG_STATUS_IDX_STATUS_RBS)
+#define ACC_REG_STATUS_MASK_STATUS_RS	BIT(ACC_REG_STATUS_IDX_STATUS_RS)
+
+static void acc_resetmode_enter(struct acc_core *core)
+{
+	acc_set_bits(core, ACC_CORE_OF_CTRL_MODE,
+		     ACC_REG_CONTROL_MASK_MODE_RESETMODE);
+
+	/* Read back reset mode bit to flush PCI write posting */
+	acc_resetmode_entered(core);
+}
+
+static void acc_resetmode_leave(struct acc_core *core)
+{
+	acc_clear_bits(core, ACC_CORE_OF_CTRL_MODE,
+		       ACC_REG_CONTROL_MASK_MODE_RESETMODE);
+
+	/* Read back reset mode bit to flush PCI write posting */
+	acc_resetmode_entered(core);
+}
+
+static void acc_txq_put(struct acc_core *core, u32 acc_id, u8 acc_dlc,
+			const void *data)
+{
+	acc_write32_noswap(core, ACC_CORE_OF_TXFIFO_DATA_1,
+			   *((const u32 *)(data + 4)));
+	acc_write32_noswap(core, ACC_CORE_OF_TXFIFO_DATA_0,
+			   *((const u32 *)data));
+	acc_write32(core, ACC_CORE_OF_TXFIFO_DLC, acc_dlc);
+	/* CAN id must be written at last. This write starts TX. */
+	acc_write32(core, ACC_CORE_OF_TXFIFO_ID, acc_id);
+}
+
+/* Convert timestamp from esdACC time stamp ticks to ns
+ *
+ * The conversion factor ts2ns from time stamp counts to ns is basically
+ *	ts2ns = NSEC_PER_SEC / timestamp_frequency
+ *
+ * We handle here only a fixed timestamp frequency of 80MHz. The
+ * resulting ts2ns factor would be 12.5.
+ *
+ * At the end we multiply by 12 and add the half of the HW timestamp
+ * to get a multiplication by 12.5. This way any overflow is
+ * avoided until ktime_t itself overflows.
+ */
+#define ACC_TS_FACTOR (NSEC_PER_SEC / ACC_TS_FREQ_80MHZ)
+#define ACC_TS_80MHZ_SHIFT 1
+
+static ktime_t acc_ts2ktime(struct acc_ov *ov, u64 ts)
+{
+	u64 ns;
+
+	ns = (ts * ACC_TS_FACTOR) + (ts >> ACC_TS_80MHZ_SHIFT);
+
+	return ns_to_ktime(ns);
+}
+
+void acc_init_ov(struct acc_ov *ov, struct device *dev)
+{
+	u32 temp;
+
+	temp = acc_ov_read32(ov, ACC_OV_OF_VERSION);
+	ov->version = temp;
+	ov->features = (temp >> 16);
+
+	temp = acc_ov_read32(ov, ACC_OV_OF_INFO);
+	ov->total_cores = temp;
+	ov->active_cores = (temp >> 8);
+
+	ov->core_frequency = acc_ov_read32(ov, ACC_OV_OF_CANCORE_FREQ);
+	ov->timestamp_frequency = acc_ov_read32(ov, ACC_OV_OF_TS_FREQ_LO);
+
+	/* Depending on ESDACC feature NEW_PSC enable the new prescaler
+	 * or adjust core_frequency according to the implicit division by 2.
+	 */
+	if (ov->features & ACC_OV_REG_FEAT_MASK_NEW_PSC) {
+		acc_ov_set_bits(ov, ACC_OV_OF_MODE,
+				ACC_OV_REG_MODE_MASK_NEW_PSC_ENABLE);
+	} else {
+		ov->core_frequency /= 2;
+	}
+
+	dev_info(dev,
+		 "ESDACC v%u, freq: %u/%u, feat/strap: 0x%x/0x%x, cores: %u/%u\n",
+		 ov->version, ov->core_frequency, ov->timestamp_frequency,
+		 ov->features, acc_ov_read32(ov, ACC_OV_OF_INFO) >> 16,
+		 ov->active_cores, ov->total_cores);
+}
+
+void acc_init_bm_ptr(struct acc_ov *ov, struct acc_core *cores, const void *mem)
+{
+	unsigned int u;
+
+	/* DMA buffer layout as follows where N is the number of CAN cores
+	 * implemented in the FPGA, i.e. N = ov->total_cores
+	 *
+	 *   Layout                   Section size
+	 * +-----------------------+
+	 * | FIFO Card/Overview	   |  ACC_CORE_DMABUF_SIZE
+	 * |			   |
+	 * +-----------------------+
+	 * | FIFO Core0		   |  ACC_CORE_DMABUF_SIZE
+	 * |			   |
+	 * +-----------------------+
+	 * | ...		   |  ...
+	 * |			   |
+	 * +-----------------------+
+	 * | FIFO CoreN		   |  ACC_CORE_DMABUF_SIZE
+	 * |			   |
+	 * +-----------------------+
+	 * | irq_cnt Card/Overview |  sizeof(u32)
+	 * +-----------------------+
+	 * | irq_cnt Core0	   |  sizeof(u32)
+	 * +-----------------------+
+	 * | ...		   |  ...
+	 * +-----------------------+
+	 * | irq_cnt CoreN	   |  sizeof(u32)
+	 * +-----------------------+
+	 */
+	ov->bmfifo.messages = mem;
+	ov->bmfifo.irq_cnt = mem + (ov->total_cores + 1U) * ACC_CORE_DMABUF_SIZE;
+
+	for (u = 0U; u < ov->active_cores; u++) {
+		struct acc_core *core = &cores[u];
+
+		core->bmfifo.messages = mem + (u + 1U) * ACC_CORE_DMABUF_SIZE;
+		core->bmfifo.irq_cnt = ov->bmfifo.irq_cnt + (u + 1U);
+	}
+}
+
+int acc_open(struct net_device *netdev)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	struct acc_core *core = priv->core;
+	u32 tx_fifo_status;
+	u32 ctrl_mode;
+	int err;
+
+	/* Retry to enter RESET mode if out of sync. */
+	if (priv->can.state != CAN_STATE_STOPPED) {
+		netdev_warn(netdev, "Entered %s() with bad can.state: %s\n",
+			    __func__, can_get_state_str(priv->can.state));
+		acc_resetmode_enter(core);
+		priv->can.state = CAN_STATE_STOPPED;
+	}
+
+	err = open_candev(netdev);
+	if (err)
+		return err;
+
+	ctrl_mode = ACC_REG_CONTROL_MASK_IE_RXTX |
+			ACC_REG_CONTROL_MASK_IE_TXERROR |
+			ACC_REG_CONTROL_MASK_IE_ERRWARN |
+			ACC_REG_CONTROL_MASK_IE_OVERRUN |
+			ACC_REG_CONTROL_MASK_IE_ERRPASS;
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
+		ctrl_mode |= ACC_REG_CONTROL_MASK_IE_BUSERR;
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+		ctrl_mode |= ACC_REG_CONTROL_MASK_MODE_LOM;
+
+	acc_set_bits(core, ACC_CORE_OF_CTRL_MODE, ctrl_mode);
+
+	acc_resetmode_leave(core);
+	priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+	/* Resync TX FIFO indices to HW state after (re-)start. */
+	tx_fifo_status = acc_read32(core, ACC_CORE_OF_TXFIFO_STATUS);
+	core->tx_fifo_head = tx_fifo_status & 0xff;
+	core->tx_fifo_tail = (tx_fifo_status >> 8) & 0xff;
+
+	netif_start_queue(netdev);
+	return 0;
+}
+
+int acc_close(struct net_device *netdev)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	struct acc_core *core = priv->core;
+
+	acc_clear_bits(core, ACC_CORE_OF_CTRL_MODE,
+		       ACC_REG_CONTROL_MASK_IE_RXTX |
+		       ACC_REG_CONTROL_MASK_IE_TXERROR |
+		       ACC_REG_CONTROL_MASK_IE_ERRWARN |
+		       ACC_REG_CONTROL_MASK_IE_OVERRUN |
+		       ACC_REG_CONTROL_MASK_IE_ERRPASS |
+		       ACC_REG_CONTROL_MASK_IE_BUSERR);
+
+	netif_stop_queue(netdev);
+	acc_resetmode_enter(core);
+	priv->can.state = CAN_STATE_STOPPED;
+
+	/* Mark pending TX requests to be aborted after controller restart. */
+	acc_write32(core, ACC_CORE_OF_TX_ABORT_MASK, 0xffff);
+
+	/* ACC_REG_CONTROL_MASK_MODE_LOM is only accessible in RESET mode */
+	acc_clear_bits(core, ACC_CORE_OF_CTRL_MODE,
+		       ACC_REG_CONTROL_MASK_MODE_LOM);
+
+	close_candev(netdev);
+	return 0;
+}
+
+netdev_tx_t acc_start_xmit(struct sk_buff *skb, struct net_device *netdev)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	struct acc_core *core = priv->core;
+	struct can_frame *cf = (struct can_frame *)skb->data;
+	u8 tx_fifo_head = core->tx_fifo_head;
+	int fifo_usage;
+	u32 acc_id;
+	u8 acc_dlc;
+
+	if (can_dropped_invalid_skb(netdev, skb))
+		return NETDEV_TX_OK;
+
+	/* Access core->tx_fifo_tail only once because it may be changed
+	 * from the interrupt level.
+	 */
+	fifo_usage = tx_fifo_head - core->tx_fifo_tail;
+	if (fifo_usage < 0)
+		fifo_usage += core->tx_fifo_size;
+
+	if (fifo_usage >= core->tx_fifo_size - 1) {
+		netdev_err(core->netdev,
+			   "BUG: TX ring full when queue awake!\n");
+		netif_stop_queue(netdev);
+		return NETDEV_TX_BUSY;
+	}
+
+	if (fifo_usage == core->tx_fifo_size - 2)
+		netif_stop_queue(netdev);
+
+	acc_dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);
+	if (cf->can_id & CAN_RTR_FLAG)
+		acc_dlc |= ACC_CAN_RTR_FLAG;
+
+	if (cf->can_id & CAN_EFF_FLAG) {
+		acc_id = cf->can_id & CAN_EFF_MASK;
+		acc_id |= ACC_CAN_EFF_FLAG;
+	} else {
+		acc_id = cf->can_id & CAN_SFF_MASK;
+	}
+
+	can_put_echo_skb(skb, netdev, core->tx_fifo_head, 0);
+
+	tx_fifo_head++;
+	if (tx_fifo_head >= core->tx_fifo_size)
+		tx_fifo_head = 0U;
+	core->tx_fifo_head = tx_fifo_head;
+
+	acc_txq_put(core, acc_id, acc_dlc, cf->data);
+
+	return NETDEV_TX_OK;
+}
+
+int acc_get_berr_counter(const struct net_device *netdev,
+			 struct can_berr_counter *bec)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	u32 core_status = acc_read32(priv->core, ACC_CORE_OF_STATUS);
+
+	bec->txerr = (core_status >> 8) & 0xff;
+	bec->rxerr = core_status & 0xff;
+
+	return 0;
+}
+
+int acc_set_mode(struct net_device *netdev, enum can_mode mode)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+
+	switch (mode) {
+	case CAN_MODE_START:
+		/* Paranoid FIFO index check. */
+		{
+			const u32 tx_fifo_status =
+				acc_read32(priv->core, ACC_CORE_OF_TXFIFO_STATUS);
+			const u8 hw_fifo_head = tx_fifo_status;
+
+			if (hw_fifo_head != priv->core->tx_fifo_head ||
+			    hw_fifo_head != priv->core->tx_fifo_tail) {
+				netdev_warn(netdev,
+					    "TX FIFO mismatch: T %2u H %2u; TFHW %#08x\n",
+					    priv->core->tx_fifo_tail,
+					    priv->core->tx_fifo_head,
+					    tx_fifo_status);
+			}
+		}
+		acc_resetmode_leave(priv->core);
+		/* To leave the bus-off state the esdACC controller begins
+		 * here a grace period where it counts 128 "idle conditions" (each
+		 * of 11 consecutive recessive bits) on the bus as required
+		 * by the CAN spec.
+		 *
+		 * During this time the TX FIFO may still contain already
+		 * aborted "zombie" frames that are only drained from the FIFO
+		 * at the end of the grace period.
+		 *
+		 * To not to interfere with this drain process we don't
+		 * call netif_wake_queue() here. When the controller reaches
+		 * the error-active state again, it informs us about that
+		 * with an acc_bmmsg_errstatechange message. Then
+		 * netif_wake_queue() is called from
+		 * handle_core_msg_errstatechange() instead.
+		 */
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+int acc_set_bittiming(struct net_device *netdev)
+{
+	struct acc_net_priv *priv = netdev_priv(netdev);
+	const struct can_bittiming *bt = &priv->can.bittiming;
+	u32 brp;
+	u32 btr;
+
+	if (priv->ov->features & ACC_OV_REG_FEAT_MASK_CANFD) {
+		u32 fbtr = 0;
+
+		netdev_dbg(netdev, "bit timing: brp %u, prop %u, ph1 %u ph2 %u, sjw %u\n",
+			   bt->brp, bt->prop_seg,
+			   bt->phase_seg1, bt->phase_seg2, bt->sjw);
+
+		brp = FIELD_PREP(ACC_REG_BRP_FD_MASK_BRP, bt->brp - 1);
+
+		btr = FIELD_PREP(ACC_REG_BTR_FD_MASK_TSEG1, bt->phase_seg1 + bt->prop_seg - 1);
+		btr |= FIELD_PREP(ACC_REG_BTR_FD_MASK_TSEG2, bt->phase_seg2 - 1);
+		btr |= FIELD_PREP(ACC_REG_BTR_FD_MASK_SJW, bt->sjw - 1);
+
+		/* Keep order of accesses to ACC_CORE_OF_BRP and ACC_CORE_OF_BTR. */
+		acc_write32(priv->core, ACC_CORE_OF_BRP, brp);
+		acc_write32(priv->core, ACC_CORE_OF_BTR, btr);
+
+		netdev_dbg(netdev, "ESDACC: BRP %u, NBTR 0x%08x, DBTR 0x%08x",
+			   brp, btr, fbtr);
+	} else {
+		netdev_dbg(netdev, "bit timing: brp %u, prop %u, ph1 %u ph2 %u, sjw %u\n",
+			   bt->brp, bt->prop_seg,
+			   bt->phase_seg1, bt->phase_seg2, bt->sjw);
+
+		brp = FIELD_PREP(ACC_REG_BRP_CL_MASK_BRP, bt->brp - 1);
+
+		btr = FIELD_PREP(ACC_REG_BTR_CL_MASK_TSEG1, bt->phase_seg1 + bt->prop_seg - 1);
+		btr |= FIELD_PREP(ACC_REG_BTR_CL_MASK_TSEG2, bt->phase_seg2 - 1);
+		btr |= FIELD_PREP(ACC_REG_BTR_CL_MASK_SJW, bt->sjw - 1);
+
+		/* Keep order of accesses to ACC_CORE_OF_BRP and ACC_CORE_OF_BTR. */
+		acc_write32(priv->core, ACC_CORE_OF_BRP, brp);
+		acc_write32(priv->core, ACC_CORE_OF_BTR, btr);
+
+		netdev_dbg(netdev, "ESDACC: BRP %u, BTR 0x%08x", brp, btr);
+	}
+
+	return 0;
+}
+
+static void handle_core_msg_rxtxdone(struct acc_core *core,
+				     const struct acc_bmmsg_rxtxdone *msg)
+{
+	struct acc_net_priv *priv = netdev_priv(core->netdev);
+	struct net_device_stats *stats = &core->netdev->stats;
+	struct sk_buff *skb;
+
+	if (msg->dlc.rxtx.len & ACC_BM_LENFLAG_TX) {
+		u8 tx_fifo_tail = core->tx_fifo_tail;
+
+		if (core->tx_fifo_head == tx_fifo_tail) {
+			netdev_warn(core->netdev,
+				    "TX interrupt, but queue is empty!?\n");
+			return;
+		}
+
+		/* Direct access echo skb to attach HW time stamp. */
+		skb = priv->can.echo_skb[tx_fifo_tail];
+		if (skb) {
+			skb_hwtstamps(skb)->hwtstamp =
+				acc_ts2ktime(priv->ov, msg->ts);
+		}
+
+		stats->tx_packets++;
+		stats->tx_bytes += can_get_echo_skb(core->netdev, tx_fifo_tail,
+						    NULL);
+
+		tx_fifo_tail++;
+		if (tx_fifo_tail >= core->tx_fifo_size)
+			tx_fifo_tail = 0U;
+		core->tx_fifo_tail = tx_fifo_tail;
+
+		netif_wake_queue(core->netdev);
+
+	} else {
+		struct can_frame *cf;
+
+		skb = alloc_can_skb(core->netdev, &cf);
+		if (!skb) {
+			stats->rx_dropped++;
+			return;
+		}
+
+		cf->can_id = msg->id & CAN_EFF_MASK;
+		if (msg->id & ACC_CAN_EFF_FLAG)
+			cf->can_id |= CAN_EFF_FLAG;
+
+		can_frame_set_cc_len(cf, msg->dlc.rx.len & ACC_CAN_DLC_MASK,
+				     priv->can.ctrlmode);
+
+		if (msg->dlc.rx.len & ACC_CAN_RTR_FLAG) {
+			cf->can_id |= CAN_RTR_FLAG;
+		} else {
+			memcpy(cf->data, msg->data, cf->len);
+			stats->rx_bytes += cf->len;
+		}
+		stats->rx_packets++;
+
+		skb_hwtstamps(skb)->hwtstamp = acc_ts2ktime(priv->ov, msg->ts);
+
+		netif_rx(skb);
+	}
+}
+
+static void handle_core_msg_txabort(struct acc_core *core,
+				    const struct acc_bmmsg_txabort *msg)
+{
+	struct net_device_stats *stats = &core->netdev->stats;
+	u8 tx_fifo_tail = core->tx_fifo_tail;
+	u32 abort_mask = msg->abort_mask;   /* u32 extend to avoid warnings later */
+
+	/* The abort_mask shows which frames were aborted in ESDACC's FIFO. */
+	while (tx_fifo_tail != core->tx_fifo_head && (abort_mask)) {
+		const u32 tail_mask = (1U << tx_fifo_tail);
+
+		if (!(abort_mask & tail_mask))
+			break;
+		abort_mask &= ~tail_mask;
+
+		can_free_echo_skb(core->netdev, tx_fifo_tail, NULL);
+		stats->tx_dropped++;
+		stats->tx_aborted_errors++;
+
+		tx_fifo_tail++;
+		if (tx_fifo_tail >= core->tx_fifo_size)
+			tx_fifo_tail = 0;
+	}
+	core->tx_fifo_tail = tx_fifo_tail;
+	if (abort_mask)
+		netdev_warn(core->netdev, "Unhandled aborted messages\n");
+
+	if (!acc_resetmode_entered(core))
+		netif_wake_queue(core->netdev);
+}
+
+static void handle_core_msg_overrun(struct acc_core *core,
+				    const struct acc_bmmsg_overrun *msg)
+{
+	struct acc_net_priv *priv = netdev_priv(core->netdev);
+	struct net_device_stats *stats = &core->netdev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+
+	/* lost_cnt may be 0 if not supported by ESDACC version */
+	if (msg->lost_cnt) {
+		stats->rx_errors += msg->lost_cnt;
+		stats->rx_over_errors += msg->lost_cnt;
+	} else {
+		stats->rx_errors++;
+		stats->rx_over_errors++;
+	}
+
+	skb = alloc_can_err_skb(core->netdev, &cf);
+	if (!skb) {
+		stats->rx_dropped++;
+		return;
+	}
+
+	cf->can_id |= CAN_ERR_CRTL;
+	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+
+	skb_hwtstamps(skb)->hwtstamp = acc_ts2ktime(priv->ov, msg->ts);
+
+	netif_rx(skb);
+}
+
+static void handle_core_msg_buserr(struct acc_core *core,
+				   const struct acc_bmmsg_buserr *msg)
+{
+	struct acc_net_priv *priv = netdev_priv(core->netdev);
+	struct net_device_stats *stats = &core->netdev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	const u32 reg_status = msg->reg_status;
+	const u8 rxerr = reg_status;
+	const u8 txerr = (reg_status >> 8);
+	u8 can_err_prot_type = 0U;
+
+	priv->can.can_stats.bus_error++;
+
+	/* Error occurred during transmission? */
+	if ((msg->ecc & ACC_ECC_DIR) == 0) {
+		can_err_prot_type |= CAN_ERR_PROT_TX;
+		stats->tx_errors++;
+	} else {
+		stats->rx_errors++;
+	}
+	/* Determine error type */
+	switch (msg->ecc & ACC_ECC_MASK) {
+	case ACC_ECC_BIT:
+		can_err_prot_type |= CAN_ERR_PROT_BIT;
+		break;
+	case ACC_ECC_FORM:
+		can_err_prot_type |= CAN_ERR_PROT_FORM;
+		break;
+	case ACC_ECC_STUFF:
+		can_err_prot_type |= CAN_ERR_PROT_STUFF;
+		break;
+	default:
+		can_err_prot_type |= CAN_ERR_PROT_UNSPEC;
+		break;
+	}
+
+	skb = alloc_can_err_skb(core->netdev, &cf);
+	if (!skb) {
+		stats->rx_dropped++;
+		return;
+	}
+
+	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+
+	/* Set protocol error type */
+	cf->data[2] = can_err_prot_type;
+	/* Set error location */
+	cf->data[3] = msg->ecc & ACC_ECC_SEG;
+
+	/* Insert CAN TX and RX error counters. */
+	cf->data[6] = txerr;
+	cf->data[7] = rxerr;
+
+	skb_hwtstamps(skb)->hwtstamp = acc_ts2ktime(priv->ov, msg->ts);
+
+	netif_rx(skb);
+}
+
+static void
+handle_core_msg_errstatechange(struct acc_core *core,
+			       const struct acc_bmmsg_errstatechange *msg)
+{
+	struct acc_net_priv *priv = netdev_priv(core->netdev);
+	struct net_device_stats *stats = &core->netdev->stats;
+	struct can_frame *cf = NULL;
+	struct sk_buff *skb;
+	const u32 reg_status = msg->reg_status;
+	const u8 rxerr = reg_status;
+	const u8 txerr = (reg_status >> 8);
+	enum can_state new_state;
+
+	if (reg_status & ACC_REG_STATUS_MASK_STATUS_BS) {
+		new_state = CAN_STATE_BUS_OFF;
+	} else if (reg_status & ACC_REG_STATUS_MASK_STATUS_EP) {
+		new_state = CAN_STATE_ERROR_PASSIVE;
+	} else if (reg_status & ACC_REG_STATUS_MASK_STATUS_ES) {
+		new_state = CAN_STATE_ERROR_WARNING;
+	} else {
+		new_state = CAN_STATE_ERROR_ACTIVE;
+		if (priv->can.state == CAN_STATE_BUS_OFF) {
+			/* See comment in acc_set_mode() for CAN_MODE_START */
+			netif_wake_queue(core->netdev);
+		}
+	}
+
+	skb = alloc_can_err_skb(core->netdev, &cf);
+
+	if (new_state != priv->can.state) {
+		enum can_state tx_state, rx_state;
+
+		tx_state = (txerr >= rxerr) ?
+			new_state : CAN_STATE_ERROR_ACTIVE;
+		rx_state = (rxerr >= txerr) ?
+			new_state : CAN_STATE_ERROR_ACTIVE;
+
+		/* Always call can_change_state() to update the state
+		 * even if alloc_can_err_skb() may have failed.
+		 * can_change_state() can cope with a NULL cf pointer.
+		 */
+		can_change_state(core->netdev, cf, tx_state, rx_state);
+	}
+
+	if (skb) {
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+
+		skb_hwtstamps(skb)->hwtstamp = acc_ts2ktime(priv->ov, msg->ts);
+
+		netif_rx(skb);
+	} else {
+		stats->rx_dropped++;
+	}
+
+	if (new_state == CAN_STATE_BUS_OFF) {
+		acc_write32(core, ACC_CORE_OF_TX_ABORT_MASK, 0xffff);
+		can_bus_off(core->netdev);
+	}
+}
+
+static void handle_core_interrupt(struct acc_core *core)
+{
+	u32 msg_fifo_head = core->bmfifo.local_irq_cnt & 0xff;
+
+	while (core->bmfifo.msg_fifo_tail != msg_fifo_head) {
+		const union acc_bmmsg *msg =
+			&core->bmfifo.messages[core->bmfifo.msg_fifo_tail];
+
+		switch (msg->msg_id) {
+		case BM_MSG_ID_RXTXDONE:
+			handle_core_msg_rxtxdone(core, &msg->rxtxdone);
+			break;
+
+		case BM_MSG_ID_TXABORT:
+			handle_core_msg_txabort(core, &msg->txabort);
+			break;
+
+		case BM_MSG_ID_OVERRUN:
+			handle_core_msg_overrun(core, &msg->overrun);
+			break;
+
+		case BM_MSG_ID_BUSERR:
+			handle_core_msg_buserr(core, &msg->buserr);
+			break;
+
+		case BM_MSG_ID_ERRPASSIVE:
+		case BM_MSG_ID_ERRWARN:
+			handle_core_msg_errstatechange(core,
+						       &msg->errstatechange);
+			break;
+
+		default:
+			/* Ignore all other BM messages (like the CAN-FD messages) */
+			break;
+		}
+
+		core->bmfifo.msg_fifo_tail =
+				(core->bmfifo.msg_fifo_tail + 1) & 0xff;
+	}
+}
+
+/**
+ * acc_card_interrupt() - handle the interrupts of an esdACC FPGA
+ *
+ * @ov: overview module structure
+ * @cores: array of core structures
+ *
+ * This function handles all interrupts pending for the overview module and the
+ * CAN cores of the esdACC FPGA.
+ *
+ * It examines for all cores (the overview module core and the CAN cores)
+ * the bmfifo.irq_cnt and compares it with the previously saved
+ * bmfifo.local_irq_cnt. An IRQ is pending if they differ. The esdACC FPGA
+ * updates the bmfifo.irq_cnt values by DMA.
+ *
+ * The pending interrupts are masked by writing to the IRQ mask register at
+ * ACC_OV_OF_BM_IRQ_MASK. This register has for each core a two bit command
+ * field evaluated as follows:
+ *
+ * Define,   bit pattern: meaning
+ *                    00: no action
+ * ACC_BM_IRQ_UNMASK, 01: unmask interrupt
+ * ACC_BM_IRQ_MASK,   10: mask interrupt
+ *                    11: no action
+ *
+ * For each CAN core with a pending IRQ handle_core_interrupt() handles all
+ * busmaster messages from the message FIFO. The last handled message (FIFO
+ * index) is written to the CAN core to acknowledge its handling.
+ *
+ * Last step is to unmask all interrupts in the FPGA using
+ * ACC_BM_IRQ_UNMASK_ALL.
+ */
+irqreturn_t acc_card_interrupt(struct acc_ov *ov, struct acc_core *cores)
+{
+	u32 irqmask;
+	int i;
+
+	/* First we look for whom interrupts are pending, card/overview
+	 * or any of the cores. Two bits in irqmask are used for each;
+	 * Each two bit field is set to ACC_BM_IRQ_MASK if an IRQ is
+	 * pending.
+	 */
+	irqmask = 0;
+	if (READ_ONCE(*ov->bmfifo.irq_cnt) != ov->bmfifo.local_irq_cnt) {
+		irqmask |= ACC_BM_IRQ_MASK;
+		ov->bmfifo.local_irq_cnt = READ_ONCE(*ov->bmfifo.irq_cnt);
+	}
+
+	for (i = 0; i < ov->active_cores; i++) {
+		struct acc_core *core = &cores[i];
+
+		if (READ_ONCE(*core->bmfifo.irq_cnt) != core->bmfifo.local_irq_cnt) {
+			irqmask |= (ACC_BM_IRQ_MASK << (2 * (i + 1)));
+			core->bmfifo.local_irq_cnt = READ_ONCE(*core->bmfifo.irq_cnt);
+		}
+	}
+
+	if (!irqmask)
+		return IRQ_NONE;
+
+	/* At second we tell the card we're working on them by writing irqmask,
+	 * call handle_{ov|core}_interrupt and then acknowledge the
+	 * interrupts by writing irq_cnt:
+	 */
+	acc_ov_write32(ov, ACC_OV_OF_BM_IRQ_MASK, irqmask);
+
+	if (irqmask & ACC_BM_IRQ_MASK) {
+		/* handle_ov_interrupt(); - no use yet. */
+		acc_ov_write32(ov, ACC_OV_OF_BM_IRQ_COUNTER,
+			       ov->bmfifo.local_irq_cnt);
+	}
+
+	for (i = 0; i < ov->active_cores; i++) {
+		struct acc_core *core = &cores[i];
+
+		if (irqmask & (ACC_BM_IRQ_MASK << (2 * (i + 1)))) {
+			handle_core_interrupt(core);
+			acc_write32(core, ACC_OV_OF_BM_IRQ_COUNTER,
+				    core->bmfifo.local_irq_cnt);
+		}
+	}
+
+	acc_ov_write32(ov, ACC_OV_OF_BM_IRQ_MASK, ACC_BM_IRQ_UNMASK_ALL);
+
+	return IRQ_HANDLED;
+}
diff --git a/drivers/net/can/esd/esdacc.h b/drivers/net/can/esd/esdacc.h
new file mode 100644
index 000000000000..73651bc1d52c
--- /dev/null
+++ b/drivers/net/can/esd/esdacc.h
@@ -0,0 +1,393 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2015 - 2016 Thomas Körper, esd electronic system design gmbh
+ * Copyright (C) 2017 - 2022 Stefan Mätje, esd electronics gmbh
+ */
+
+#include <linux/bits.h>
+#include <linux/can/dev.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/units.h>
+
+#define ACC_TS_FREQ_80MHZ			(80 * HZ_PER_MHZ)
+
+#define ACC_CAN_EFF_FLAG			0x20000000
+#define ACC_CAN_RTR_FLAG			0x10
+#define ACC_CAN_DLC_MASK			0x0f
+
+#define ACC_OV_OF_PROBE				0x0000
+#define ACC_OV_OF_VERSION			0x0004
+#define ACC_OV_OF_INFO				0x0008
+#define ACC_OV_OF_CANCORE_FREQ			0x000c
+#define ACC_OV_OF_TS_FREQ_LO			0x0010
+#define ACC_OV_OF_TS_FREQ_HI			0x0014
+#define ACC_OV_OF_IRQ_STATUS_CORES		0x0018
+#define ACC_OV_OF_TS_CURR_LO			0x001c
+#define ACC_OV_OF_TS_CURR_HI			0x0020
+#define ACC_OV_OF_IRQ_STATUS			0x0028
+#define ACC_OV_OF_MODE				0x002c
+#define ACC_OV_OF_BM_IRQ_COUNTER		0x0070
+#define ACC_OV_OF_BM_IRQ_MASK			0x0074
+#define ACC_OV_OF_MSI_DATA			0x0080
+#define ACC_OV_OF_MSI_ADDRESSOFFSET		0x0084
+
+/* Feature flags are contained in the upper 16 bit of the version
+ * register at ACC_OV_OF_VERSION but only used with these masks after
+ * extraction into an extra variable => (xx - 16).
+ */
+#define ACC_OV_REG_FEAT_IDX_CANFD		(27 - 16)
+#define ACC_OV_REG_FEAT_IDX_NEW_PSC		(28 - 16)
+#define ACC_OV_REG_FEAT_MASK_CANFD		BIT(ACC_OV_REG_FEAT_IDX_CANFD)
+#define ACC_OV_REG_FEAT_MASK_NEW_PSC		BIT(ACC_OV_REG_FEAT_IDX_NEW_PSC)
+
+#define ACC_OV_REG_MODE_MASK_ENDIAN_LITTLE	0x00000001
+#define ACC_OV_REG_MODE_MASK_BM_ENABLE		0x00000002
+#define ACC_OV_REG_MODE_MASK_MODE_LED		0x00000004
+#define ACC_OV_REG_MODE_MASK_TIMER		0x00000070
+#define ACC_OV_REG_MODE_MASK_TIMER_ENABLE	0x00000010
+#define ACC_OV_REG_MODE_MASK_TIMER_ONE_SHOT	0x00000020
+#define ACC_OV_REG_MODE_MASK_TIMER_ABSOLUTE	0x00000040
+#define ACC_OV_REG_MODE_MASK_TS_SRC		0x00000180
+#define ACC_OV_REG_MODE_MASK_I2C_ENABLE		0x00000800
+#define ACC_OV_REG_MODE_MASK_MSI_ENABLE		0x00004000
+#define ACC_OV_REG_MODE_MASK_NEW_PSC_ENABLE	0x00008000
+#define ACC_OV_REG_MODE_MASK_FPGA_RESET		0x80000000
+
+#define ACC_CORE_OF_CTRL_MODE			0x0000
+#define ACC_CORE_OF_STATUS_IRQ			0x0008
+#define ACC_CORE_OF_BRP				0x000c
+#define ACC_CORE_OF_BTR				0x0010
+#define ACC_CORE_OF_FBTR			0x0014
+#define ACC_CORE_OF_STATUS			0x0030
+#define ACC_CORE_OF_TXFIFO_CONFIG		0x0048
+#define ACC_CORE_OF_TXFIFO_STATUS		0x004c
+#define ACC_CORE_OF_TX_STATUS_IRQ		0x0050
+#define ACC_CORE_OF_TX_ABORT_MASK		0x0054
+#define ACC_CORE_OF_BM_IRQ_COUNTER		0x0070
+#define ACC_CORE_OF_TXFIFO_ID			0x00c0
+#define ACC_CORE_OF_TXFIFO_DLC			0x00c4
+#define ACC_CORE_OF_TXFIFO_DATA_0		0x00c8
+#define ACC_CORE_OF_TXFIFO_DATA_1		0x00cc
+
+#define ACC_REG_CONTROL_IDX_MODE_RESETMODE	0
+#define ACC_REG_CONTROL_IDX_MODE_LOM		1
+#define ACC_REG_CONTROL_IDX_MODE_STM		2
+#define ACC_REG_CONTROL_IDX_MODE_TRANSEN	5
+#define ACC_REG_CONTROL_IDX_MODE_TS		6
+#define ACC_REG_CONTROL_IDX_MODE_SCHEDULE	7
+#define ACC_REG_CONTROL_MASK_MODE_RESETMODE	\
+				BIT(ACC_REG_CONTROL_IDX_MODE_RESETMODE)
+#define ACC_REG_CONTROL_MASK_MODE_LOM		\
+				BIT(ACC_REG_CONTROL_IDX_MODE_LOM)
+#define ACC_REG_CONTROL_MASK_MODE_STM		\
+				BIT(ACC_REG_CONTROL_IDX_MODE_STM)
+#define ACC_REG_CONTROL_MASK_MODE_TRANSEN	\
+				BIT(ACC_REG_CONTROL_IDX_MODE_TRANSEN)
+#define ACC_REG_CONTROL_MASK_MODE_TS		\
+				BIT(ACC_REG_CONTROL_IDX_MODE_TS)
+#define ACC_REG_CONTROL_MASK_MODE_SCHEDULE	\
+				BIT(ACC_REG_CONTROL_IDX_MODE_SCHEDULE)
+
+#define ACC_REG_CONTROL_IDX_IE_RXTX	8
+#define ACC_REG_CONTROL_IDX_IE_TXERROR	9
+#define ACC_REG_CONTROL_IDX_IE_ERRWARN	10
+#define ACC_REG_CONTROL_IDX_IE_OVERRUN	11
+#define ACC_REG_CONTROL_IDX_IE_TSI	12
+#define ACC_REG_CONTROL_IDX_IE_ERRPASS	13
+#define ACC_REG_CONTROL_IDX_IE_BUSERR	15
+#define ACC_REG_CONTROL_MASK_IE_RXTX	BIT(ACC_REG_CONTROL_IDX_IE_RXTX)
+#define ACC_REG_CONTROL_MASK_IE_TXERROR BIT(ACC_REG_CONTROL_IDX_IE_TXERROR)
+#define ACC_REG_CONTROL_MASK_IE_ERRWARN BIT(ACC_REG_CONTROL_IDX_IE_ERRWARN)
+#define ACC_REG_CONTROL_MASK_IE_OVERRUN BIT(ACC_REG_CONTROL_IDX_IE_OVERRUN)
+#define ACC_REG_CONTROL_MASK_IE_TSI	BIT(ACC_REG_CONTROL_IDX_IE_TSI)
+#define ACC_REG_CONTROL_MASK_IE_ERRPASS BIT(ACC_REG_CONTROL_IDX_IE_ERRPASS)
+#define ACC_REG_CONTROL_MASK_IE_BUSERR	BIT(ACC_REG_CONTROL_IDX_IE_BUSERR)
+
+/* BRP and BTR register layout for CAN-Classic version */
+#define ACC_REG_BRP_CL_MASK_BRP         GENMASK(8, 0)
+#define ACC_REG_BTR_CL_MASK_TSEG1       GENMASK(3, 0)
+#define ACC_REG_BTR_CL_MASK_TSEG2       GENMASK(18, 16)
+#define ACC_REG_BTR_CL_MASK_SJW         GENMASK(25, 24)
+
+/* BRP and BTR register layout for CAN-FD version */
+#define ACC_REG_BRP_FD_MASK_BRP         GENMASK(7, 0)
+#define ACC_REG_BTR_FD_MASK_TSEG1       GENMASK(7, 0)
+#define ACC_REG_BTR_FD_MASK_TSEG2       GENMASK(22, 16)
+#define ACC_REG_BTR_FD_MASK_SJW         GENMASK(30, 24)
+
+/* 256 BM_MSGs of 32 byte size */
+#define ACC_CORE_DMAMSG_SIZE		32U
+#define ACC_CORE_DMABUF_SIZE		(256U * ACC_CORE_DMAMSG_SIZE)
+
+enum acc_bmmsg_id {
+	BM_MSG_ID_RXTXDONE = 0x01,
+	BM_MSG_ID_TXABORT = 0x02,
+	BM_MSG_ID_OVERRUN = 0x03,
+	BM_MSG_ID_BUSERR = 0x04,
+	BM_MSG_ID_ERRPASSIVE = 0x05,
+	BM_MSG_ID_ERRWARN = 0x06,
+	BM_MSG_ID_TIMESLICE = 0x07,
+	BM_MSG_ID_HWTIMER = 0x08,
+	BM_MSG_ID_HOTPLUG = 0x09,
+};
+
+/* The struct acc_bmmsg_* structure declarations that follow here provide
+ * access to the ring buffer of bus master messages maintained by the FPGA
+ * bus master engine. All bus master messages have the same size of
+ * ACC_CORE_DMAMSG_SIZE and a minimum alignment of ACC_CORE_DMAMSG_SIZE in
+ * memory.
+ *
+ * All structure members are natural aligned. Therefore we should not need
+ * a __packed attribute. All struct acc_bmmsg_* declarations have at least
+ * reserved* members to fill the structure to the full ACC_CORE_DMAMSG_SIZE.
+ *
+ * A failure of this property due padding will be detected at compile time
+ * by static_assert(sizeof(union acc_bmmsg) == ACC_CORE_DMAMSG_SIZE).
+ */
+
+struct acc_bmmsg_rxtxdone {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 reserved1[2];
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u32 id;
+	union {
+		struct {
+			u8 len;
+			u8 reserved0;
+			u8 bits;
+			u8 state;
+		} rxtx;
+		struct {
+			u8 len;
+			u8 msg_lost;
+			u8 bits;
+			u8 state;
+		} rx;
+		struct {
+			u8 len;
+			u8 txfifo_idx;
+			u8 bits;
+			u8 state;
+		} tx;
+	} dlc;
+	u8 data[8];
+	/* Time stamps in struct acc_ov::timestamp_frequency ticks. */
+	u64 ts;
+};
+
+struct acc_bmmsg_txabort {
+	u8 msg_id;
+	u8 txfifo_level;
+	u16 abort_mask;
+	u8 txtsfifo_level;
+	u8 reserved2[1];
+	u16 abort_mask_txts;
+	u64 ts;
+	u32 reserved3[4];
+};
+
+struct acc_bmmsg_overrun {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 lost_cnt;
+	u8 reserved1;
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u64 ts;
+	u32 reserved3[4];
+};
+
+struct acc_bmmsg_buserr {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 ecc;
+	u8 reserved1;
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u64 ts;
+	u32 reg_status;
+	u32 reg_btr;
+	u32 reserved3[2];
+};
+
+struct acc_bmmsg_errstatechange {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 reserved1[2];
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u64 ts;
+	u32 reg_status;
+	u32 reserved3[3];
+};
+
+struct acc_bmmsg_timeslice {
+	u8 msg_id;
+	u8 txfifo_level;
+	u8 reserved1[2];
+	u8 txtsfifo_level;
+	u8 reserved2[3];
+	u64 ts;
+	u32 reserved3[4];
+};
+
+struct acc_bmmsg_hwtimer {
+	u8 msg_id;
+	u8 reserved1[3];
+	u32 reserved2[1];
+	u64 timer;
+	u32 reserved3[4];
+};
+
+struct acc_bmmsg_hotplug {
+	u8 msg_id;
+	u8 reserved1[3];
+	u32 reserved2[7];
+};
+
+union acc_bmmsg {
+	u8 msg_id;
+	struct acc_bmmsg_rxtxdone rxtxdone;
+	struct acc_bmmsg_txabort txabort;
+	struct acc_bmmsg_overrun overrun;
+	struct acc_bmmsg_buserr buserr;
+	struct acc_bmmsg_errstatechange errstatechange;
+	struct acc_bmmsg_timeslice timeslice;
+	struct acc_bmmsg_hwtimer hwtimer;
+};
+
+/* Check size of union acc_bmmsg to be of expected size. */
+static_assert(sizeof(union acc_bmmsg) == ACC_CORE_DMAMSG_SIZE);
+
+struct acc_bmfifo {
+	const union acc_bmmsg *messages;
+	/* irq_cnt points to an u32 value where the ESDACC FPGA deposits
+	 * the bm_fifo head index in coherent DMA memory. Only bits 7..0
+	 * are valid. Use READ_ONCE() to access this memory location.
+	 */
+	const u32 *irq_cnt;
+	u32 local_irq_cnt;
+	u32 msg_fifo_tail;
+};
+
+struct acc_core {
+	void __iomem *addr;
+	struct net_device *netdev;
+	struct acc_bmfifo bmfifo;
+	u8 tx_fifo_size;
+	u8 tx_fifo_head;
+	u8 tx_fifo_tail;
+};
+
+struct acc_ov {
+	void __iomem *addr;
+	struct acc_bmfifo bmfifo;
+	u32 timestamp_frequency;
+	u32 core_frequency;
+	u16 version;
+	u16 features;
+	u8 total_cores;
+	u8 active_cores;
+};
+
+struct acc_net_priv {
+	struct can_priv can; /* must be the first member! */
+	struct acc_core *core;
+	struct acc_ov *ov;
+};
+
+static inline u32 acc_read32(struct acc_core *core, unsigned short offs)
+{
+	return ioread32be(core->addr + offs);
+}
+
+static inline void acc_write32(struct acc_core *core,
+			       unsigned short offs, u32 v)
+{
+	iowrite32be(v, core->addr + offs);
+}
+
+static inline void acc_write32_noswap(struct acc_core *core,
+				      unsigned short offs, u32 v)
+{
+	iowrite32(v, core->addr + offs);
+}
+
+static inline void acc_set_bits(struct acc_core *core,
+				unsigned short offs, u32 mask)
+{
+	u32 v = acc_read32(core, offs);
+
+	v |= mask;
+	acc_write32(core, offs, v);
+}
+
+static inline void acc_clear_bits(struct acc_core *core,
+				  unsigned short offs, u32 mask)
+{
+	u32 v = acc_read32(core, offs);
+
+	v &= ~mask;
+	acc_write32(core, offs, v);
+}
+
+static inline int acc_resetmode_entered(struct acc_core *core)
+{
+	u32 ctrl = acc_read32(core, ACC_CORE_OF_CTRL_MODE);
+
+	return (ctrl & ACC_REG_CONTROL_MASK_MODE_RESETMODE) != 0;
+}
+
+static inline u32 acc_ov_read32(struct acc_ov *ov, unsigned short offs)
+{
+	return ioread32be(ov->addr + offs);
+}
+
+static inline void acc_ov_write32(struct acc_ov *ov,
+				  unsigned short offs, u32 v)
+{
+	iowrite32be(v, ov->addr + offs);
+}
+
+static inline void acc_ov_set_bits(struct acc_ov *ov,
+				   unsigned short offs, u32 b)
+{
+	u32 v = acc_ov_read32(ov, offs);
+
+	v |= b;
+	acc_ov_write32(ov, offs, v);
+}
+
+static inline void acc_ov_clear_bits(struct acc_ov *ov,
+				     unsigned short offs, u32 b)
+{
+	u32 v = acc_ov_read32(ov, offs);
+
+	v &= ~b;
+	acc_ov_write32(ov, offs, v);
+}
+
+static inline void acc_reset_fpga(struct acc_ov *ov)
+{
+	acc_ov_write32(ov, ACC_OV_OF_MODE, ACC_OV_REG_MODE_MASK_FPGA_RESET);
+
+	/* Also reset I^2C, to re-detect card addons at every driver start: */
+	acc_ov_clear_bits(ov, ACC_OV_OF_MODE, ACC_OV_REG_MODE_MASK_I2C_ENABLE);
+	mdelay(2);
+	acc_ov_set_bits(ov, ACC_OV_OF_MODE, ACC_OV_REG_MODE_MASK_I2C_ENABLE);
+	mdelay(10);
+}
+
+void acc_init_ov(struct acc_ov *ov, struct device *dev);
+void acc_init_bm_ptr(struct acc_ov *ov, struct acc_core *cores,
+		     const void *mem);
+int acc_open(struct net_device *netdev);
+int acc_close(struct net_device *netdev);
+netdev_tx_t acc_start_xmit(struct sk_buff *skb, struct net_device *netdev);
+int acc_get_berr_counter(const struct net_device *netdev,
+			 struct can_berr_counter *bec);
+int acc_set_mode(struct net_device *netdev, enum can_mode mode);
+int acc_set_bittiming(struct net_device *netdev);
+irqreturn_t acc_card_interrupt(struct acc_ov *ov, struct acc_core *cores);