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@xxxxxx> Signed-off-by: Thomas Körper <thomas.koerper@xxxxxx> Signed-off-by: Stefan Mätje <stefan.maetje@xxxxxx> --- 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 diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig index cd34e8dc9394..5a1c2cbb93e0 100644 --- a/drivers/net/can/Kconfig +++ b/drivers/net/can/Kconfig @@ -201,6 +201,7 @@ 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 52b0f6e10668..8ab8b30d381e 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@xxxxxx>"); +MODULE_AUTHOR("Stefan Mätje <stefan.maetje@xxxxxx>"); +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); -- 2.25.1
