From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> This patch adds support for the Microchip MCP25xxFD SPI CAN controller family. Tested-by: Kurt Van Dijck <dev.kurt@xxxxxxxxxxxxxxxxxxxxxx> Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> --- drivers/net/can/spi/mcp25xxfd/Makefile | 1 + .../net/can/spi/mcp25xxfd/mcp25xxfd-core.c | 2880 +++++++++++++++++ 2 files changed, 2881 insertions(+) create mode 100644 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c diff --git a/drivers/net/can/spi/mcp25xxfd/Makefile b/drivers/net/can/spi/mcp25xxfd/Makefile index 9dadf0070b42..4e17f592e22e 100644 --- a/drivers/net/can/spi/mcp25xxfd/Makefile +++ b/drivers/net/can/spi/mcp25xxfd/Makefile @@ -3,5 +3,6 @@ obj-$(CONFIG_CAN_MCP25XXFD) += mcp25xxfd.o mcp25xxfd-objs := +mcp25xxfd-objs += mcp25xxfd-core.o mcp25xxfd-objs += mcp25xxfd-crc16.o mcp25xxfd-objs += mcp25xxfd-regmap.o diff --git a/drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c b/drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c new file mode 100644 index 000000000000..eea3ef69f585 --- /dev/null +++ b/drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c @@ -0,0 +1,2880 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// mcp25xxfd - Microchip MCP25xxFD Family CAN controller driver +// +// Copyright (c) 2019, 2020 Pengutronix, +// Marc Kleine-Budde <kernel@xxxxxxxxxxxxxx> +// +// Based on: +// +// CAN bus driver for Microchip 25XXFD CAN Controller with SPI Interface +// +// Copyright (c) 2019 Martin Sperl <kernel@xxxxxxxxxxxxxxxx> +// + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/pm_runtime.h> + +#include <asm/unaligned.h> + +#include "mcp25xxfd.h" + +#define DEVICE_NAME "mcp25xxfd" + +static const struct mcp25xxfd_devtype_data mcp25xxfd_devtype_data_mcp2517fd = { + .quirks = MCP25XXFD_QUIRK_MAB_NO_WARN | MCP25XXFD_QUIRK_CRC_REG | + MCP25XXFD_QUIRK_CRC_RX | MCP25XXFD_QUIRK_CRC_TX | + MCP25XXFD_QUIRK_ECC, + .model = MCP25XXFD_MODEL_MCP2517FD, +}; + +static const struct mcp25xxfd_devtype_data mcp25xxfd_devtype_data_mcp2518fd = { + .quirks = MCP25XXFD_QUIRK_CRC_REG | MCP25XXFD_QUIRK_CRC_RX | + MCP25XXFD_QUIRK_CRC_TX | MCP25XXFD_QUIRK_ECC, + .model = MCP25XXFD_MODEL_MCP2518FD, +}; + +/* Autodetect model, start with CRC enabled. */ +static const struct mcp25xxfd_devtype_data mcp25xxfd_devtype_data_mcp25xxfd = { + .quirks = MCP25XXFD_QUIRK_CRC_REG | MCP25XXFD_QUIRK_CRC_RX | + MCP25XXFD_QUIRK_CRC_TX | MCP25XXFD_QUIRK_ECC, + .model = MCP25XXFD_MODEL_MCP25XXFD, +}; + +static const struct can_bittiming_const mcp25xxfd_bittiming_const = { + .name = DEVICE_NAME, + .tseg1_min = 2, + .tseg1_max = 256, + .tseg2_min = 1, + .tseg2_max = 128, + .sjw_max = 128, + .brp_min = 1, + .brp_max = 256, + .brp_inc = 1, +}; + +static const struct can_bittiming_const mcp25xxfd_data_bittiming_const = { + .name = DEVICE_NAME, + .tseg1_min = 1, + .tseg1_max = 32, + .tseg2_min = 1, + .tseg2_max = 16, + .sjw_max = 16, + .brp_min = 1, + .brp_max = 256, + .brp_inc = 1, +}; + +static const char *__mcp25xxfd_get_model_str(enum mcp25xxfd_model model) +{ + switch (model) { + case MCP25XXFD_MODEL_MCP2517FD: + return "MCP2517FD"; break; + case MCP25XXFD_MODEL_MCP2518FD: + return "MCP2518FD"; break; + case MCP25XXFD_MODEL_MCP25XXFD: + return "MCP25xxFD"; break; + } + + return "<unknown>"; +} + +static inline const char * +mcp25xxfd_get_model_str(const struct mcp25xxfd_priv *priv) +{ + return __mcp25xxfd_get_model_str(priv->devtype_data.model); +} + +static const char *mcp25xxfd_get_mode_str(const u8 mode) +{ + switch (mode) { + case MCP25XXFD_REG_CON_MODE_MIXED: + return "Mixed (CAN FD/CAN 2.0)"; break; + case MCP25XXFD_REG_CON_MODE_SLEEP: + return "Sleep"; break; + case MCP25XXFD_REG_CON_MODE_INT_LOOPBACK: + return "Internal Loopback"; break; + case MCP25XXFD_REG_CON_MODE_LISTENONLY: + return "Listen Only"; break; + case MCP25XXFD_REG_CON_MODE_CONFIG: + return "Configuration"; break; + case MCP25XXFD_REG_CON_MODE_EXT_LOOPBACK: + return "External Loopback"; break; + case MCP25XXFD_REG_CON_MODE_CAN2_0: + return "CAN 2.0"; break; + case MCP25XXFD_REG_CON_MODE_RESTRICTED: + return "Restricted Operation"; break; + } + + return "<unknown>"; +} + +static inline int mcp25xxfd_vdd_enable(const struct mcp25xxfd_priv *priv) +{ + if (!priv->reg_vdd) + return 0; + + return regulator_enable(priv->reg_vdd); +} + +static inline int mcp25xxfd_vdd_disable(const struct mcp25xxfd_priv *priv) +{ + if (!priv->reg_vdd) + return 0; + + return regulator_disable(priv->reg_vdd); +} + +static inline int +mcp25xxfd_transceiver_enable(const struct mcp25xxfd_priv *priv) +{ + if (!priv->reg_xceiver) + return 0; + + return regulator_enable(priv->reg_xceiver); +} + +static inline int +mcp25xxfd_transceiver_disable(const struct mcp25xxfd_priv *priv) +{ + if (!priv->reg_xceiver) + return 0; + + return regulator_disable(priv->reg_xceiver); +} + +static int mcp25xxfd_clks_and_vdd_enable(const struct mcp25xxfd_priv *priv) +{ + int err; + + err = clk_prepare_enable(priv->clk); + if (err) + return err; + + err = mcp25xxfd_vdd_enable(priv); + if (err) + clk_disable_unprepare(priv->clk); + + /* Wait for oscillator stabilisation time after power up */ + usleep_range(MCP25XXFD_OSC_STAB_SLEEP_US, + 2 * MCP25XXFD_OSC_STAB_SLEEP_US); + + return err; +} + +static int mcp25xxfd_clks_and_vdd_disable(const struct mcp25xxfd_priv *priv) +{ + int err; + + err = mcp25xxfd_vdd_disable(priv); + if (err) + return err; + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static inline u8 +mcp25xxfd_cmd_prepare_write_reg(const struct mcp25xxfd_priv *priv, + union mcp25xxfd_write_reg_buf *write_reg_buf, + const u16 reg, const u32 mask, const u32 val) +{ + u8 first_byte, last_byte, len; + u8 *data; + __le32 val_le32; + + first_byte = mcp25xxfd_first_byte_set(mask); + last_byte = mcp25xxfd_last_byte_set(mask); + len = last_byte - first_byte + 1; + + data = mcp25xxfd_spi_cmd_write(priv, write_reg_buf, reg + first_byte); + val_le32 = cpu_to_le32(val >> BITS_PER_BYTE * first_byte); + memcpy(data, &val_le32, len); + + if (priv->devtype_data.quirks & MCP25XXFD_QUIRK_CRC_REG) { + u16 crc; + + mcp25xxfd_spi_cmd_crc_set_len_in_reg(&write_reg_buf->crc.cmd, + len); + /* CRC */ + len += sizeof(write_reg_buf->crc.cmd); + crc = mcp25xxfd_crc16_compute(&write_reg_buf->crc, len); + put_unaligned_be16(crc, (void *)write_reg_buf + len); + + /* Total length */ + len += sizeof(write_reg_buf->crc.crc); + } else { + len += sizeof(write_reg_buf->nocrc.cmd); + } + + return len; +} + +static inline int +mcp25xxfd_tef_tail_get_from_chip(const struct mcp25xxfd_priv *priv, + u8 *tef_tail) +{ + u32 tef_ua; + int err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_TEFUA, &tef_ua); + if (err) + return err; + + *tef_tail = tef_ua / sizeof(struct mcp25xxfd_hw_tef_obj); + + return 0; +} + +static inline int +mcp25xxfd_tx_tail_get_from_chip(const struct mcp25xxfd_priv *priv, + u8 *tx_tail) +{ + u32 fifo_sta; + int err; + + err = regmap_read(priv->map_reg, + MCP25XXFD_REG_FIFOSTA(MCP25XXFD_TX_FIFO), + &fifo_sta); + if (err) + return err; + + *tx_tail = FIELD_GET(MCP25XXFD_REG_FIFOSTA_FIFOCI_MASK, fifo_sta); + + return 0; +} + +static inline int +mcp25xxfd_rx_head_get_from_chip(const struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_rx_ring *ring, + u8 *rx_head) +{ + u32 fifo_sta; + int err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_FIFOSTA(ring->fifo_nr), + &fifo_sta); + if (err) + return err; + + *rx_head = FIELD_GET(MCP25XXFD_REG_FIFOSTA_FIFOCI_MASK, fifo_sta); + + return 0; +} + +static inline int +mcp25xxfd_rx_tail_get_from_chip(const struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_rx_ring *ring, + u8 *rx_tail) +{ + u32 fifo_ua; + int err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_FIFOUA(ring->fifo_nr), + &fifo_ua); + if (err) + return err; + + fifo_ua -= ring->base - MCP25XXFD_RAM_START; + *rx_tail = fifo_ua / ring->obj_size; + + return 0; +} + +static void +mcp25xxfd_tx_ring_init_tx_obj(const struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_tx_ring *ring, + struct mcp25xxfd_tx_obj *tx_obj, + const u8 rts_buf_len, + const u8 n) +{ + struct spi_transfer *xfer; + u16 addr; + + /* FIFO load */ + addr = mcp25xxfd_get_tx_obj_addr(ring, n); + if (priv->devtype_data.quirks & MCP25XXFD_QUIRK_CRC_TX) + mcp25xxfd_spi_cmd_write_crc_set_addr(&tx_obj->buf.crc.cmd, + addr); + else + mcp25xxfd_spi_cmd_write_nocrc(&tx_obj->buf.nocrc.cmd, + addr); + + xfer = &tx_obj->xfer[0]; + xfer->tx_buf = &tx_obj->buf; + xfer->len = 0; /* actual len is assigned on the fly */ + xfer->cs_change = 1; + xfer->cs_change_delay.value = 0; + xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; + + /* FIFO request to send */ + xfer = &tx_obj->xfer[1]; + xfer->tx_buf = &ring->rts_buf; + xfer->len = rts_buf_len; + + /* SPI message */ + spi_message_init_with_transfers(&tx_obj->msg, tx_obj->xfer, + ARRAY_SIZE(tx_obj->xfer)); +} + +static void mcp25xxfd_ring_init(struct mcp25xxfd_priv *priv) +{ + struct mcp25xxfd_tx_ring *tx_ring; + struct mcp25xxfd_rx_ring *rx_ring, *prev_rx_ring = NULL; + struct mcp25xxfd_tx_obj *tx_obj; + u32 val; + u16 addr; + u8 len; + int i; + + /* TEF */ + priv->tef.head = 0; + priv->tef.tail = 0; + + /* TX */ + tx_ring = priv->tx; + tx_ring->head = 0; + tx_ring->tail = 0; + tx_ring->base = mcp25xxfd_get_tef_obj_addr(tx_ring->obj_num); + + /* FIFO request to send */ + addr = MCP25XXFD_REG_FIFOCON(MCP25XXFD_TX_FIFO); + val = MCP25XXFD_REG_FIFOCON_TXREQ | MCP25XXFD_REG_FIFOCON_UINC; + len = mcp25xxfd_cmd_prepare_write_reg(priv, &tx_ring->rts_buf, + addr, val, val); + + mcp25xxfd_for_each_tx_obj(tx_ring, tx_obj, i) + mcp25xxfd_tx_ring_init_tx_obj(priv, tx_ring, tx_obj, len, i); + + /* RX */ + mcp25xxfd_for_each_rx_ring(priv, rx_ring, i) { + rx_ring->head = 0; + rx_ring->tail = 0; + rx_ring->nr = i; + rx_ring->fifo_nr = MCP25XXFD_RX_FIFO(i); + + if (!prev_rx_ring) + rx_ring->base = + mcp25xxfd_get_tx_obj_addr(tx_ring, + tx_ring->obj_num); + else + rx_ring->base = prev_rx_ring->base + + prev_rx_ring->obj_size * + prev_rx_ring->obj_num; + + prev_rx_ring = rx_ring; + } +} + +static void mcp25xxfd_ring_free(struct mcp25xxfd_priv *priv) +{ + int i; + + for (i = ARRAY_SIZE(priv->rx) - 1; i > 0; i--) { + kfree(priv->rx[i]); + priv->rx[i] = NULL; + } +} + +static int mcp25xxfd_ring_alloc(struct mcp25xxfd_priv *priv) +{ + struct mcp25xxfd_tx_ring *tx_ring; + struct mcp25xxfd_rx_ring *rx_ring; + int tef_obj_size, tx_obj_size, rx_obj_size; + int tx_obj_num; + int ram_free, i; + + tef_obj_size = sizeof(struct mcp25xxfd_hw_tef_obj); + if (priv->can.ctrlmode & CAN_CTRLMODE_FD) { + tx_obj_num = MCP25XXFD_TX_OBJ_NUM_CANFD; + tx_obj_size = sizeof(struct mcp25xxfd_hw_tx_obj_canfd); + rx_obj_size = sizeof(struct mcp25xxfd_hw_rx_obj_canfd); + } else { + tx_obj_num = MCP25XXFD_TX_OBJ_NUM_CAN; + tx_obj_size = sizeof(struct mcp25xxfd_hw_tx_obj_can); + rx_obj_size = sizeof(struct mcp25xxfd_hw_rx_obj_can); + } + + tx_ring = priv->tx; + tx_ring->obj_num = tx_obj_num; + tx_ring->obj_size = tx_obj_size; + + ram_free = MCP25XXFD_RAM_SIZE - tx_obj_num * + (tef_obj_size + tx_obj_size); + + for (i = 0; + i < ARRAY_SIZE(priv->rx) && ram_free >= rx_obj_size; + i++) { + int rx_obj_num; + + rx_obj_num = ram_free / rx_obj_size; + rx_obj_num = min(1 << (fls(rx_obj_num) - 1), 32); + + rx_ring = kzalloc(sizeof(*rx_ring) + rx_obj_size * rx_obj_num, + GFP_KERNEL); + if (!rx_ring) { + mcp25xxfd_ring_free(priv); + return -ENOMEM; + } + rx_ring->obj_num = rx_obj_num; + rx_ring->obj_size = rx_obj_size; + priv->rx[i] = rx_ring; + + ram_free -= rx_ring->obj_num * rx_ring->obj_size; + } + priv->rx_ring_num = i; + + netdev_dbg(priv->ndev, + "FIFO setup: TEF: %d*%d bytes = %d bytes, TX: %d*%d bytes = %d bytes\n", + tx_obj_num, tef_obj_size, tef_obj_size * tx_obj_num, + tx_obj_num, tx_obj_size, tx_obj_size * tx_obj_num); + + mcp25xxfd_for_each_rx_ring(priv, rx_ring, i) { + netdev_dbg(priv->ndev, + "FIFO setup: RX-%d: %d*%d bytes = %d bytes\n", + i, rx_ring->obj_num, rx_ring->obj_size, + rx_ring->obj_size * rx_ring->obj_num); + } + + netdev_dbg(priv->ndev, + "FIFO setup: free: %d bytes\n", + ram_free); + + return 0; +} + +static inline int +mcp25xxfd_chip_get_mode(const struct mcp25xxfd_priv *priv, u8 *mode) +{ + u32 val; + int err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_CON, &val); + if (err) + return err; + + *mode = FIELD_GET(MCP25XXFD_REG_CON_OPMOD_MASK, val); + + return 0; +} + +static int +__mcp25xxfd_chip_set_mode(const struct mcp25xxfd_priv *priv, + const u8 mode_req, bool nowait) +{ + u32 con, con_reqop; + int err; + + con_reqop = FIELD_PREP(MCP25XXFD_REG_CON_REQOP_MASK, mode_req); + err = regmap_update_bits(priv->map_reg, MCP25XXFD_REG_CON, + MCP25XXFD_REG_CON_REQOP_MASK, con_reqop); + if (err) + return err; + + if (mode_req == MCP25XXFD_REG_CON_MODE_SLEEP || nowait) + return 0; + + err = regmap_read_poll_timeout(priv->map_reg, MCP25XXFD_REG_CON, con, + FIELD_GET(MCP25XXFD_REG_CON_OPMOD_MASK, + con) == mode_req, + MCP25XXFD_POLL_SLEEP_US, + MCP25XXFD_POLL_TIMEOUT_US); + if (err) { + u8 mode = FIELD_GET(MCP25XXFD_REG_CON_OPMOD_MASK, con); + + netdev_err(priv->ndev, + "Controller failed to enter mode %s Mode (%u) and stays in %s Mode (%u).\n", + mcp25xxfd_get_mode_str(mode_req), mode_req, + mcp25xxfd_get_mode_str(mode), mode); + return err; + } + + return 0; +} + +static inline int +mcp25xxfd_chip_set_mode(const struct mcp25xxfd_priv *priv, + const u8 mode_req) +{ + return __mcp25xxfd_chip_set_mode(priv, mode_req, false); +} + +static inline int +mcp25xxfd_chip_set_mode_nowait(const struct mcp25xxfd_priv *priv, + const u8 mode_req) +{ + return __mcp25xxfd_chip_set_mode(priv, mode_req, true); +} + +static inline bool mcp25xxfd_osc_invalid(u32 reg) +{ + return reg == 0x0 || reg == 0xffffffff; +} + +static int mcp25xxfd_chip_clock_enable(const struct mcp25xxfd_priv *priv) +{ + u32 osc, osc_reference, osc_mask; + int err; + + /* Set Power On Defaults for "Clock Output Divisor" and remove + * "Oscillator Disable" bit. + */ + osc = FIELD_PREP(MCP25XXFD_REG_OSC_CLKODIV_MASK, + MCP25XXFD_REG_OSC_CLKODIV_10); + osc_reference = MCP25XXFD_REG_OSC_OSCRDY; + osc_mask = MCP25XXFD_REG_OSC_OSCRDY | MCP25XXFD_REG_OSC_PLLRDY; + + /* Note: + * + * If the controller is in Sleep Mode the following write only + * removes the "Oscillator Disable" bit and powers it up. All + * other bits are unaffected. + */ + err = regmap_write(priv->map_reg, MCP25XXFD_REG_OSC, osc); + if (err) + return err; + + /* Wait for "Oscillator Ready" bit */ + err = regmap_read_poll_timeout(priv->map_reg, MCP25XXFD_REG_OSC, osc, + (osc & osc_mask) == osc_reference, + MCP25XXFD_OSC_STAB_SLEEP_US, + MCP25XXFD_OSC_STAB_TIMEOUT_US); + if (mcp25xxfd_osc_invalid(osc)) { + netdev_err(priv->ndev, + "Failed to detect %s (osc=0x%08x).\n", + mcp25xxfd_get_model_str(priv), osc); + return -ENODEV; + } else if (err == -ETIMEDOUT) { + netdev_err(priv->ndev, + "Timeout waiting for Oscillator Ready (osc=0x%08x, osc_reference=0x%08x)\n", + osc, osc_reference); + return -ETIMEDOUT; + } else if (err) { + return err; + } + + return 0; +} + +static int mcp25xxfd_chip_softreset_do(const struct mcp25xxfd_priv *priv) +{ + const __be16 cmd = mcp25xxfd_cmd_reset(); + int err; + + /* The Set Mode and SPI Reset command only seems to works if + * the controller is not in Sleep Mode. + */ + err = mcp25xxfd_chip_clock_enable(priv); + if (err) + return err; + + err = mcp25xxfd_chip_set_mode(priv, MCP25XXFD_REG_CON_MODE_CONFIG); + if (err) + return err; + + /* spi_write_then_read() works with non DMA-safe buffers */ + return spi_write_then_read(priv->spi, &cmd, sizeof(cmd), NULL, 0); +} + +static int mcp25xxfd_chip_softreset_check(const struct mcp25xxfd_priv *priv) +{ + u32 osc, osc_reference; + u8 mode; + int err; + + err = mcp25xxfd_chip_get_mode(priv, &mode); + if (err) + return err; + + if (mode != MCP25XXFD_REG_CON_MODE_CONFIG) { + netdev_info(priv->ndev, + "Controller not in Config Mode after reset, but in %s Mode (%u).\n", + mcp25xxfd_get_mode_str(mode), mode); + return -ETIMEDOUT; + } + + osc_reference = MCP25XXFD_REG_OSC_OSCRDY | + FIELD_PREP(MCP25XXFD_REG_OSC_CLKODIV_MASK, + MCP25XXFD_REG_OSC_CLKODIV_10); + + /* check reset defaults of OSC reg */ + err = regmap_read(priv->map_reg, MCP25XXFD_REG_OSC, &osc); + if (err) + return err; + + if (osc != osc_reference) { + netdev_info(priv->ndev, + "Controller failed to reset. osc=0x%08x, reference value=0x%08x\n", + osc, osc_reference); + return -ETIMEDOUT; + } + + return 0; +} + +static int mcp25xxfd_chip_softreset(const struct mcp25xxfd_priv *priv) +{ + int err, i; + + for (i = 0; i < MCP25XXFD_SOFTRESET_RETRIES_MAX; i++) { + if (i) + netdev_info(priv->ndev, + "Retrying to reset Controller.\n"); + + err = mcp25xxfd_chip_softreset_do(priv); + if (err == -ETIMEDOUT) + continue; + if (err) + return err; + + err = mcp25xxfd_chip_softreset_check(priv); + if (err == -ETIMEDOUT) + continue; + if (err) + return err; + + return 0; + } + + if (err) + return err; + + return -ETIMEDOUT; +} + +static int mcp25xxfd_chip_clock_init(const struct mcp25xxfd_priv *priv) +{ + u32 osc; + int err; + + /* Activate Low Power Mode on Oscillator Disable. This only + * works on the MCP2518FD. The MCP2517FD will go into normal + * Sleep Mode instead. + */ + osc = MCP25XXFD_REG_OSC_LPMEN | + FIELD_PREP(MCP25XXFD_REG_OSC_CLKODIV_MASK, + MCP25XXFD_REG_OSC_CLKODIV_10); + err = regmap_write(priv->map_reg, MCP25XXFD_REG_OSC, osc); + if (err) + return err; + + /* Set Time Base Counter Prescaler to 1. + * + * This means an overflow of the 32 bit Time Base Counter + * register at 40 MHz every 107 seconds. + */ + return regmap_write(priv->map_reg, MCP25XXFD_REG_TSCON, + MCP25XXFD_REG_TSCON_TBCEN); +} + +static int mcp25xxfd_set_bittiming(const struct mcp25xxfd_priv *priv) +{ + const struct can_bittiming *bt = &priv->can.bittiming; + const struct can_bittiming *dbt = &priv->can.data_bittiming; + u32 val = 0; + s8 tdco; + int err; + + /* CAN Control Register + * + * - no transmit bandwidth sharing + * - config mode + * - disable transmit queue + * - store in transmit FIFO event + * - transition to restricted operation mode on system error + * - ESI is transmitted recessive when ESI of message is high or + * CAN controller error passive + * - restricted retransmission attempts, + * use TQXCON_TXAT and FIFOCON_TXAT + * - wake-up filter bits T11FILTER + * - use CAN bus line filter for wakeup + * - protocol exception is treated as a form error + * - Do not compare data bytes + */ + val = FIELD_PREP(MCP25XXFD_REG_CON_REQOP_MASK, + MCP25XXFD_REG_CON_MODE_CONFIG) | + MCP25XXFD_REG_CON_STEF | + MCP25XXFD_REG_CON_ESIGM | + MCP25XXFD_REG_CON_RTXAT | + FIELD_PREP(MCP25XXFD_REG_CON_WFT_MASK, + MCP25XXFD_REG_CON_WFT_T11FILTER) | + MCP25XXFD_REG_CON_WAKFIL | + MCP25XXFD_REG_CON_PXEDIS; + + if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)) + val |= MCP25XXFD_REG_CON_ISOCRCEN; + + err = regmap_write(priv->map_reg, MCP25XXFD_REG_CON, val); + if (err) + return err; + + /* Nominal Bit Time */ + val = FIELD_PREP(MCP25XXFD_REG_NBTCFG_BRP_MASK, bt->brp - 1) | + FIELD_PREP(MCP25XXFD_REG_NBTCFG_TSEG1_MASK, + bt->prop_seg + bt->phase_seg1 - 1) | + FIELD_PREP(MCP25XXFD_REG_NBTCFG_TSEG2_MASK, + bt->phase_seg2 - 1) | + FIELD_PREP(MCP25XXFD_REG_NBTCFG_SJW_MASK, bt->sjw - 1); + + err = regmap_write(priv->map_reg, MCP25XXFD_REG_NBTCFG, val); + if (err) + return err; + + if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD)) + return 0; + + /* Data Bit Time */ + val = FIELD_PREP(MCP25XXFD_REG_DBTCFG_BRP_MASK, dbt->brp - 1) | + FIELD_PREP(MCP25XXFD_REG_DBTCFG_TSEG1_MASK, + dbt->prop_seg + dbt->phase_seg1 - 1) | + FIELD_PREP(MCP25XXFD_REG_DBTCFG_TSEG2_MASK, + dbt->phase_seg2 - 1) | + FIELD_PREP(MCP25XXFD_REG_DBTCFG_SJW_MASK, dbt->sjw - 1); + + err = regmap_write(priv->map_reg, MCP25XXFD_REG_DBTCFG, val); + if (err) + return err; + + /* Transmitter Delay Compensation */ + tdco = clamp_t(int, dbt->brp * (dbt->prop_seg + dbt->phase_seg1), + -64, 63); + val = FIELD_PREP(MCP25XXFD_REG_TDC_TDCMOD_MASK, + MCP25XXFD_REG_TDC_TDCMOD_AUTO) | + FIELD_PREP(MCP25XXFD_REG_TDC_TDCO_MASK, tdco); + + return regmap_write(priv->map_reg, MCP25XXFD_REG_TDC, val); +} + +static int mcp25xxfd_chip_rx_int_enable(const struct mcp25xxfd_priv *priv) +{ + u32 val; + + if (!priv->rx_int) + return 0; + + /* Configure GPIOs: + * - PIN0: GPIO Input + * - PIN1: GPIO Input/RX Interrupt + * + * PIN1 must be Input, otherwise there is a glitch on the + * rx-INT line. It happens between setting the PIN as output + * (in the first byte of the SPI transfer) and configuring the + * PIN as interrupt (in the last byte of the SPI transfer). + */ + val = MCP25XXFD_REG_IOCON_PM0 | MCP25XXFD_REG_IOCON_TRIS1 | + MCP25XXFD_REG_IOCON_TRIS0; + return regmap_write(priv->map_reg, MCP25XXFD_REG_IOCON, val); +} + +static int mcp25xxfd_chip_rx_int_disable(const struct mcp25xxfd_priv *priv) +{ + u32 val; + + if (!priv->rx_int) + return 0; + + /* Configure GPIOs: + * - PIN0: GPIO Input + * - PIN1: GPIO Input + */ + val = MCP25XXFD_REG_IOCON_PM1 | MCP25XXFD_REG_IOCON_PM0 | + MCP25XXFD_REG_IOCON_TRIS1 | MCP25XXFD_REG_IOCON_TRIS0; + return regmap_write(priv->map_reg, MCP25XXFD_REG_IOCON, val); +} + +static int +mcp25xxfd_chip_rx_fifo_init_one(const struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_rx_ring *ring) +{ + u32 fifo_con; + + /* Enable RXOVIE on _all_ RX FIFOs, not just the last one. + * + * FIFOs hit by a RX MAB overflow and RXOVIE enabled will + * generate a RXOVIF, use this to properly detect RX MAB + * overflows. + */ + fifo_con = FIELD_PREP(MCP25XXFD_REG_FIFOCON_FSIZE_MASK, + ring->obj_num - 1) | + MCP25XXFD_REG_FIFOCON_RXTSEN | + MCP25XXFD_REG_FIFOCON_RXOVIE | + MCP25XXFD_REG_FIFOCON_TFNRFNIE; + + if (priv->can.ctrlmode & CAN_CTRLMODE_FD) + fifo_con |= FIELD_PREP(MCP25XXFD_REG_FIFOCON_PLSIZE_MASK, + MCP25XXFD_REG_FIFOCON_PLSIZE_64); + else + fifo_con |= FIELD_PREP(MCP25XXFD_REG_FIFOCON_PLSIZE_MASK, + MCP25XXFD_REG_FIFOCON_PLSIZE_8); + + return regmap_write(priv->map_reg, + MCP25XXFD_REG_FIFOCON(ring->fifo_nr), fifo_con); +} + +static int +mcp25xxfd_chip_rx_filter_init_one(const struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_rx_ring *ring) +{ + u32 fltcon; + + fltcon = MCP25XXFD_REG_FLTCON_FLTEN(ring->nr) | + MCP25XXFD_REG_FLTCON_FBP(ring->nr, ring->fifo_nr); + + return regmap_update_bits(priv->map_reg, + MCP25XXFD_REG_FLTCON(ring->nr >> 2), + MCP25XXFD_REG_FLTCON_FLT_MASK(ring->nr), + fltcon); +} + +static int mcp25xxfd_chip_fifo_init(const struct mcp25xxfd_priv *priv) +{ + const struct mcp25xxfd_tx_ring *tx_ring = priv->tx; + const struct mcp25xxfd_rx_ring *rx_ring; + u32 val; + int err, n; + + /* TEF */ + val = FIELD_PREP(MCP25XXFD_REG_TEFCON_FSIZE_MASK, + tx_ring->obj_num - 1) | + MCP25XXFD_REG_TEFCON_TEFTSEN | + MCP25XXFD_REG_TEFCON_TEFOVIE | + MCP25XXFD_REG_TEFCON_TEFNEIE; + + err = regmap_write(priv->map_reg, MCP25XXFD_REG_TEFCON, val); + if (err) + return err; + + /* FIFO 1 - TX */ + val = FIELD_PREP(MCP25XXFD_REG_FIFOCON_FSIZE_MASK, + tx_ring->obj_num - 1) | + MCP25XXFD_REG_FIFOCON_TXEN | + MCP25XXFD_REG_FIFOCON_TXATIE; + + if (priv->can.ctrlmode & CAN_CTRLMODE_FD) + val |= FIELD_PREP(MCP25XXFD_REG_FIFOCON_PLSIZE_MASK, + MCP25XXFD_REG_FIFOCON_PLSIZE_64); + else + val |= FIELD_PREP(MCP25XXFD_REG_FIFOCON_PLSIZE_MASK, + MCP25XXFD_REG_FIFOCON_PLSIZE_8); + + if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT) + val |= FIELD_PREP(MCP25XXFD_REG_FIFOCON_TXAT_MASK, + MCP25XXFD_REG_FIFOCON_TXAT_ONE_SHOT); + else + val |= FIELD_PREP(MCP25XXFD_REG_FIFOCON_TXAT_MASK, + MCP25XXFD_REG_FIFOCON_TXAT_UNLIMITED); + + err = regmap_write(priv->map_reg, + MCP25XXFD_REG_FIFOCON(MCP25XXFD_TX_FIFO), + val); + if (err) + return err; + + /* RX FIFOs */ + mcp25xxfd_for_each_rx_ring(priv, rx_ring, n) { + err = mcp25xxfd_chip_rx_fifo_init_one(priv, rx_ring); + if (err) + return err; + + err = mcp25xxfd_chip_rx_filter_init_one(priv, rx_ring); + if (err) + return err; + } + + return 0; +} + +static int mcp25xxfd_chip_ecc_init(struct mcp25xxfd_priv *priv) +{ + struct mcp25xxfd_ecc *ecc = &priv->ecc; + void *ram; + u32 val = 0; + int err; + + ecc->ecc_stat = 0; + + if (priv->devtype_data.quirks & MCP25XXFD_QUIRK_ECC) + val = MCP25XXFD_REG_ECCCON_ECCEN; + + err = regmap_update_bits(priv->map_reg, MCP25XXFD_REG_ECCCON, + MCP25XXFD_REG_ECCCON_ECCEN, val); + if (err) + return err; + + ram = kzalloc(MCP25XXFD_RAM_SIZE, GFP_KERNEL); + if (!ram) + return -ENOMEM; + + err = regmap_raw_write(priv->map_reg, MCP25XXFD_RAM_START, ram, + MCP25XXFD_RAM_SIZE); + kfree(ram); + + return err; +} + +static inline void mcp25xxfd_ecc_tefif_successful(struct mcp25xxfd_priv *priv) +{ + struct mcp25xxfd_ecc *ecc = &priv->ecc; + + ecc->ecc_stat = 0; +} + +static u8 mcp25xxfd_get_normal_mode(const struct mcp25xxfd_priv *priv) +{ + u8 mode; + + if (priv->can.ctrlmode & CAN_CTRLMODE_FD) + mode = MCP25XXFD_REG_CON_MODE_MIXED; + else + mode = MCP25XXFD_REG_CON_MODE_CAN2_0; + + return mode; +} + +static int +__mcp25xxfd_chip_set_normal_mode(const struct mcp25xxfd_priv *priv, + bool nowait) +{ + u8 mode; + + mode = mcp25xxfd_get_normal_mode(priv); + + return __mcp25xxfd_chip_set_mode(priv, mode, nowait); +} + +static inline int +mcp25xxfd_chip_set_normal_mode(const struct mcp25xxfd_priv *priv) +{ + return __mcp25xxfd_chip_set_normal_mode(priv, false); +} + +static inline int +mcp25xxfd_chip_set_normal_mode_nowait(const struct mcp25xxfd_priv *priv) +{ + return __mcp25xxfd_chip_set_normal_mode(priv, true); +} + +static int mcp25xxfd_chip_interrupts_enable(const struct mcp25xxfd_priv *priv) +{ + u32 val; + int err; + + err = mcp25xxfd_chip_rx_int_enable(priv); + if (err) + return err; + + val = MCP25XXFD_REG_CRC_FERRIE | MCP25XXFD_REG_CRC_CRCERRIE; + err = regmap_write(priv->map_reg, MCP25XXFD_REG_CRC, val); + if (err) + return err; + + val = MCP25XXFD_REG_ECCCON_DEDIE | MCP25XXFD_REG_ECCCON_SECIE; + err = regmap_update_bits(priv->map_reg, MCP25XXFD_REG_ECCCON, val, val); + if (err) + return err; + + val = MCP25XXFD_REG_INT_CERRIE | + MCP25XXFD_REG_INT_SERRIE | + MCP25XXFD_REG_INT_RXOVIE | + MCP25XXFD_REG_INT_TXATIE | + MCP25XXFD_REG_INT_SPICRCIE | + MCP25XXFD_REG_INT_ECCIE | + MCP25XXFD_REG_INT_TEFIE | + MCP25XXFD_REG_INT_MODIE | + MCP25XXFD_REG_INT_RXIE; + + if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) + val |= MCP25XXFD_REG_INT_IVMIE; + + return regmap_write(priv->map_reg, MCP25XXFD_REG_INT, val); +} + +static int mcp25xxfd_chip_interrupts_disable(const struct mcp25xxfd_priv *priv) +{ + int err; + u32 mask; + + err = regmap_write(priv->map_reg, MCP25XXFD_REG_INT, 0); + if (err) + return err; + + mask = MCP25XXFD_REG_ECCCON_DEDIE | MCP25XXFD_REG_ECCCON_SECIE; + err = regmap_update_bits(priv->map_reg, MCP25XXFD_REG_ECCCON, + mask, 0x0); + if (err) + return err; + + err = regmap_write(priv->map_reg, MCP25XXFD_REG_CRC, 0); + if (err) + return err; + + return mcp25xxfd_chip_rx_int_disable(priv); +} + +static int mcp25xxfd_chip_stop(struct mcp25xxfd_priv *priv, + const enum can_state state) +{ + priv->can.state = state; + + mcp25xxfd_chip_interrupts_disable(priv); + return mcp25xxfd_chip_set_mode(priv, MCP25XXFD_REG_CON_MODE_SLEEP); +} + +static int mcp25xxfd_chip_start(struct mcp25xxfd_priv *priv) +{ + int err; + + err = mcp25xxfd_chip_softreset(priv); + if (err) + goto out_chip_stop; + + err = mcp25xxfd_chip_clock_init(priv); + if (err) + goto out_chip_stop; + + err = mcp25xxfd_set_bittiming(priv); + if (err) + goto out_chip_stop; + + err = mcp25xxfd_chip_ecc_init(priv); + if (err) + goto out_chip_stop; + + mcp25xxfd_ring_init(priv); + + err = mcp25xxfd_chip_fifo_init(priv); + if (err) + goto out_chip_stop; + + priv->can.state = CAN_STATE_ERROR_ACTIVE; + + err = mcp25xxfd_chip_set_normal_mode(priv); + if (err) + goto out_chip_stop; + + return 0; + + out_chip_stop: + mcp25xxfd_chip_stop(priv, CAN_STATE_STOPPED); + + return err; +} + +static int mcp25xxfd_set_mode(struct net_device *ndev, enum can_mode mode) +{ + struct mcp25xxfd_priv *priv = netdev_priv(ndev); + int err; + + switch (mode) { + case CAN_MODE_START: + err = mcp25xxfd_chip_start(priv); + if (err) + return err; + + err = mcp25xxfd_chip_interrupts_enable(priv); + if (err) { + mcp25xxfd_chip_stop(priv, CAN_STATE_STOPPED); + return err; + } + + netif_wake_queue(ndev); + break; + + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int __mcp25xxfd_get_berr_counter(const struct net_device *ndev, + struct can_berr_counter *bec) +{ + const struct mcp25xxfd_priv *priv = netdev_priv(ndev); + u32 trec; + int err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_TREC, &trec); + if (err) + return err; + + if (trec & MCP25XXFD_REG_TREC_TXBO) + bec->txerr = 256; + else + bec->txerr = FIELD_GET(MCP25XXFD_REG_TREC_TEC_MASK, trec); + bec->rxerr = FIELD_GET(MCP25XXFD_REG_TREC_REC_MASK, trec); + + return 0; +} + +static int mcp25xxfd_get_berr_counter(const struct net_device *ndev, + struct can_berr_counter *bec) +{ + const struct mcp25xxfd_priv *priv = netdev_priv(ndev); + + /* Avoid waking up the controller if the interface is down */ + if (!(ndev->flags & IFF_UP)) + return 0; + + /* The controller is powered down during Bus Off, use saved + * bec values. + */ + if (priv->can.state == CAN_STATE_BUS_OFF) { + *bec = priv->bec; + return 0; + } + + return __mcp25xxfd_get_berr_counter(ndev, bec); +} + +static int mcp25xxfd_check_tef_tail(const struct mcp25xxfd_priv *priv) +{ + u8 tef_tail_chip, tef_tail; + int err; + + if (!IS_ENABLED(CONFIG_CAN_MCP25XXFD_SANITY)) + return 0; + + err = mcp25xxfd_tef_tail_get_from_chip(priv, &tef_tail_chip); + if (err) + return err; + + tef_tail = mcp25xxfd_get_tef_tail(priv); + if (tef_tail_chip != tef_tail) { + netdev_err(priv->ndev, + "TEF tail of chip (0x%02x) and ours (0x%08x) inconsistent.\n", + tef_tail_chip, tef_tail); + return -EILSEQ; + } + + return 0; +} + +static int +mcp25xxfd_check_rx_tail(const struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_rx_ring *ring) +{ + u8 rx_tail_chip, rx_tail; + int err; + + if (!IS_ENABLED(CONFIG_CAN_MCP25XXFD_SANITY)) + return 0; + + err = mcp25xxfd_rx_tail_get_from_chip(priv, ring, &rx_tail_chip); + if (err) + return err; + + rx_tail = mcp25xxfd_get_rx_tail(ring); + if (rx_tail_chip != rx_tail) { + netdev_err(priv->ndev, + "RX tail of chip (%d) and ours (%d) inconsistent.\n", + rx_tail_chip, rx_tail); + return -EILSEQ; + } + + return 0; +} + +static int +mcp25xxfd_handle_tefif_recover(const struct mcp25xxfd_priv *priv, const u32 seq) +{ + const struct mcp25xxfd_tx_ring *tx_ring = priv->tx; + u32 tef_sta; + int err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_TEFSTA, &tef_sta); + if (err) + return err; + + if (tef_sta & MCP25XXFD_REG_TEFSTA_TEFOVIF) { + netdev_err(priv->ndev, + "Transmit Event FIFO buffer overflow.\n"); + return -ENOBUFS; + } + + netdev_info(priv->ndev, + "Transmit Event FIFO buffer %s. (seq=0x%08x, tef_tail=0x%08x, tef_head=0x%08x, tx_head=0x%08x)\n", + tef_sta & MCP25XXFD_REG_TEFSTA_TEFFIF ? + "full" : tef_sta & MCP25XXFD_REG_TEFSTA_TEFNEIF ? + "not empty" : "empty", + seq, priv->tef.tail, priv->tef.head, tx_ring->head); + + /* The Sequence Number in the TEF doesn't match our tef_tail. */ + return -EAGAIN; +} + +static int +mcp25xxfd_handle_tefif_one(struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_hw_tef_obj *hw_tef_obj) +{ + struct mcp25xxfd_tx_ring *tx_ring = priv->tx; + struct net_device_stats *stats = &priv->ndev->stats; + u32 seq, seq_masked, tef_tail_masked; + int err; + + seq = FIELD_GET(MCP25XXFD_OBJ_FLAGS_SEQ_MCP2518FD_MASK, + hw_tef_obj->flags); + + /* Use the MCP2517FD mask on the MCP2518FD, too. We only + * compare 7 bits, this should be enough to detect + * net-yet-completed, i.e. old TEF objects. + */ + seq_masked = seq & + field_mask(MCP25XXFD_OBJ_FLAGS_SEQ_MCP2517FD_MASK); + tef_tail_masked = priv->tef.tail & + field_mask(MCP25XXFD_OBJ_FLAGS_SEQ_MCP2517FD_MASK); + if (seq_masked != tef_tail_masked) + return mcp25xxfd_handle_tefif_recover(priv, seq); + + stats->tx_bytes += + can_rx_offload_get_echo_skb(&priv->offload, + mcp25xxfd_get_tef_tail(priv), + hw_tef_obj->ts); + stats->tx_packets++; + + /* finally increment the TEF pointer */ + err = regmap_update_bits(priv->map_reg, MCP25XXFD_REG_TEFCON, + GENMASK(15, 8), + MCP25XXFD_REG_TEFCON_UINC); + if (err) + return err; + + priv->tef.tail++; + tx_ring->tail++; + + return mcp25xxfd_check_tef_tail(priv); +} + +static int mcp25xxfd_tef_ring_update(struct mcp25xxfd_priv *priv) +{ + const struct mcp25xxfd_tx_ring *tx_ring = priv->tx; + unsigned int new_head; + u8 chip_tx_tail; + int err; + + err = mcp25xxfd_tx_tail_get_from_chip(priv, &chip_tx_tail); + if (err) + return err; + + /* chip_tx_tail, is the next TX-Object send by the HW. + * The new TEF head must be >= the old head, ... + */ + new_head = round_down(priv->tef.head, tx_ring->obj_num) + chip_tx_tail; + if (new_head <= priv->tef.head) + new_head += tx_ring->obj_num; + + /* ... but it cannot exceed the TX head. */ + priv->tef.head = min(new_head, tx_ring->head); + + return mcp25xxfd_check_tef_tail(priv); +} + +static inline int +mcp25xxfd_tef_obj_read(const struct mcp25xxfd_priv *priv, + struct mcp25xxfd_hw_tef_obj *hw_tef_obj, + const u8 offset, const u8 len) +{ + const struct mcp25xxfd_tx_ring *tx_ring = priv->tx; + + if (IS_ENABLED(CONFIG_CAN_MCP25XXFD_SANITY) && + (offset > tx_ring->obj_num || + len > tx_ring->obj_num || + offset + len > tx_ring->obj_num)) { + netdev_err(priv->ndev, + "Trying to read to many TEF objects (max=%d, offset=%d, len=%d).\n", + tx_ring->obj_num, offset, len); + return -ERANGE; + } + + return regmap_bulk_read(priv->map_rx, + mcp25xxfd_get_tef_obj_addr(offset), + hw_tef_obj, + sizeof(*hw_tef_obj) / sizeof(u32) * len); +} + +static int mcp25xxfd_handle_tefif(struct mcp25xxfd_priv *priv) +{ + struct mcp25xxfd_hw_tef_obj hw_tef_obj[MCP25XXFD_TX_OBJ_NUM_MAX]; + u8 tef_tail, len, l; + int err, i; + + err = mcp25xxfd_tef_ring_update(priv); + if (err) + return err; + + tef_tail = mcp25xxfd_get_tef_tail(priv); + len = mcp25xxfd_get_tef_len(priv); + l = mcp25xxfd_get_tef_linear_len(priv); + err = mcp25xxfd_tef_obj_read(priv, hw_tef_obj, tef_tail, l); + if (err) + return err; + + if (l < len) { + err = mcp25xxfd_tef_obj_read(priv, &hw_tef_obj[l], 0, len - l); + if (err) + return err; + } + + for (i = 0; i < len; i++) { + err = mcp25xxfd_handle_tefif_one(priv, &hw_tef_obj[i]); + /* -EAGAIN means the Sequence Number in the TEF + * doesn't match our tef_tail. This can happen if we + * read the TEF objects too early. Leave loop let the + * interrupt handler call us again. + */ + if (err == -EAGAIN) + goto out_netif_wake_queue; + if (err) + return err; + } + + out_netif_wake_queue: + mcp25xxfd_ecc_tefif_successful(priv); + netif_wake_queue(priv->ndev); + + return 0; +} + +static int +mcp25xxfd_rx_ring_update(const struct mcp25xxfd_priv *priv, + struct mcp25xxfd_rx_ring *ring) +{ + u32 new_head; + u8 chip_rx_head; + int err; + + err = mcp25xxfd_rx_head_get_from_chip(priv, ring, &chip_rx_head); + if (err) + return err; + + /* chip_rx_head, is the next RX-Object filled by the HW. + * The new RX head must be >= the old head. + */ + new_head = round_down(ring->head, ring->obj_num) + chip_rx_head; + if (new_head <= ring->head) + new_head += ring->obj_num; + + ring->head = new_head; + + return mcp25xxfd_check_rx_tail(priv, ring); +} + +static void +mcp25xxfd_hw_rx_obj_to_skb(const struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_hw_rx_obj_canfd *hw_rx_obj, + struct sk_buff *skb) +{ + struct canfd_frame *cfd = (struct canfd_frame *)skb->data; + + if (hw_rx_obj->flags & MCP25XXFD_OBJ_FLAGS_IDE) { + u32 sid, eid; + + eid = FIELD_GET(MCP25XXFD_OBJ_ID_EID_MASK, hw_rx_obj->id); + sid = FIELD_GET(MCP25XXFD_OBJ_ID_SID_MASK, hw_rx_obj->id); + + cfd->can_id = CAN_EFF_FLAG | + FIELD_PREP(MCP25XXFD_REG_FRAME_EFF_EID_MASK, eid) | + FIELD_PREP(MCP25XXFD_REG_FRAME_EFF_SID_MASK, sid); + } else { + cfd->can_id = FIELD_GET(MCP25XXFD_OBJ_ID_SID_MASK, + hw_rx_obj->id); + } + + /* CANFD */ + if (hw_rx_obj->flags & MCP25XXFD_OBJ_FLAGS_FDF) { + u8 dlc; + + if (hw_rx_obj->flags & MCP25XXFD_OBJ_FLAGS_ESI) + cfd->flags |= CANFD_ESI; + + if (hw_rx_obj->flags & MCP25XXFD_OBJ_FLAGS_BRS) + cfd->flags |= CANFD_BRS; + + dlc = FIELD_GET(MCP25XXFD_OBJ_FLAGS_DLC, hw_rx_obj->flags); + cfd->len = can_dlc2len(get_canfd_dlc(dlc)); + } else { + if (hw_rx_obj->flags & MCP25XXFD_OBJ_FLAGS_RTR) + cfd->can_id |= CAN_RTR_FLAG; + + cfd->len = get_can_dlc(FIELD_GET(MCP25XXFD_OBJ_FLAGS_DLC, + hw_rx_obj->flags)); + } + + memcpy(cfd->data, hw_rx_obj->data, cfd->len); +} + +static int +mcp25xxfd_handle_rxif_one(struct mcp25xxfd_priv *priv, + struct mcp25xxfd_rx_ring *ring, + const struct mcp25xxfd_hw_rx_obj_canfd *hw_rx_obj) +{ + struct net_device_stats *stats = &priv->ndev->stats; + struct sk_buff *skb; + struct canfd_frame *cfd; + int err; + + if (hw_rx_obj->flags & MCP25XXFD_OBJ_FLAGS_FDF) + skb = alloc_canfd_skb(priv->ndev, &cfd); + else + skb = alloc_can_skb(priv->ndev, (struct can_frame **)&cfd); + + if (!cfd) { + stats->rx_dropped++; + return 0; + } + + mcp25xxfd_hw_rx_obj_to_skb(priv, hw_rx_obj, skb); + err = can_rx_offload_queue_sorted(&priv->offload, skb, hw_rx_obj->ts); + if (err) + stats->rx_fifo_errors++; + + ring->tail++; + + /* finally increment the RX pointer */ + return regmap_update_bits(priv->map_reg, + MCP25XXFD_REG_FIFOCON(ring->fifo_nr), + GENMASK(15, 8), + MCP25XXFD_REG_FIFOCON_UINC); +} + +static inline int +mcp25xxfd_rx_obj_read(const struct mcp25xxfd_priv *priv, + const struct mcp25xxfd_rx_ring *ring, + struct mcp25xxfd_hw_rx_obj_canfd *hw_rx_obj, + const u8 offset, const u8 len) +{ + int err; + + err = regmap_bulk_read(priv->map_rx, + mcp25xxfd_get_rx_obj_addr(ring, offset), + hw_rx_obj, + len * ring->obj_size / sizeof(u32)); + + return err; +} + +static int +mcp25xxfd_handle_rxif_ring(struct mcp25xxfd_priv *priv, + struct mcp25xxfd_rx_ring *ring) +{ + struct mcp25xxfd_hw_rx_obj_canfd *hw_rx_obj = ring->obj; + u8 rx_tail, len; + int err, i; + + err = mcp25xxfd_rx_ring_update(priv, ring); + if (err) + return err; + + while ((len = mcp25xxfd_get_rx_linear_len(ring))) { + rx_tail = mcp25xxfd_get_rx_tail(ring); + + err = mcp25xxfd_rx_obj_read(priv, ring, hw_rx_obj, + rx_tail, len); + if (err) + return err; + + for (i = 0; i < len; i++) { + err = mcp25xxfd_handle_rxif_one(priv, ring, + (void *)hw_rx_obj + + i * ring->obj_size); + if (err) + return err; + } + } + + return 0; +} + +static int mcp25xxfd_handle_rxif(struct mcp25xxfd_priv *priv) +{ + struct mcp25xxfd_rx_ring *ring; + int err, n; + + mcp25xxfd_for_each_rx_ring(priv, ring, n) { + err = mcp25xxfd_handle_rxif_ring(priv, ring); + if (err) + return err; + } + + return 0; +} + +static inline int mcp25xxfd_get_timestamp(const struct mcp25xxfd_priv *priv, + u32 *timestamp) +{ + return regmap_read(priv->map_reg, MCP25XXFD_REG_TBC, timestamp); +} + +static struct sk_buff * +mcp25xxfd_alloc_can_err_skb(const struct mcp25xxfd_priv *priv, + struct can_frame **cf, u32 *timestamp) +{ + int err; + + err = mcp25xxfd_get_timestamp(priv, timestamp); + if (err) + return NULL; + + return alloc_can_err_skb(priv->ndev, cf); +} + +static int mcp25xxfd_handle_rxovif(struct mcp25xxfd_priv *priv) +{ + struct net_device_stats *stats = &priv->ndev->stats; + struct mcp25xxfd_rx_ring *ring; + struct sk_buff *skb; + struct can_frame *cf; + u32 timestamp, rxovif; + int err, i; + + stats->rx_over_errors++; + stats->rx_errors++; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_RXOVIF, &rxovif); + if (err) + return err; + + mcp25xxfd_for_each_rx_ring(priv, ring, i) { + if (!(rxovif & BIT(ring->fifo_nr))) + continue; + + /* If SERRIF is active, there was a RX MAB overflow. */ + if (priv->regs_status.intf & MCP25XXFD_REG_INT_SERRIF) { + netdev_info(priv->ndev, + "RX-%d: MAB overflow detected.\n", + ring->nr); + } else { + netdev_info(priv->ndev, + "RX-%d: FIFO overflow.\n", ring->nr); + } + + err = regmap_update_bits(priv->map_reg, + MCP25XXFD_REG_FIFOSTA(ring->fifo_nr), + MCP25XXFD_REG_FIFOSTA_RXOVIF, + 0x0); + if (err) + return err; + } + + skb = mcp25xxfd_alloc_can_err_skb(priv, &cf, ×tamp); + if (!skb) + return 0; + + cf->can_id |= CAN_ERR_CRTL; + cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; + + err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp); + if (err) + stats->rx_fifo_errors++; + + return 0; +} + +static int mcp25xxfd_handle_txatif(struct mcp25xxfd_priv *priv) +{ + netdev_info(priv->ndev, "%s\n", __func__); + + return 0; +} + +static int mcp25xxfd_handle_ivmif(struct mcp25xxfd_priv *priv) +{ + struct net_device_stats *stats = &priv->ndev->stats; + u32 bdiag1, timestamp; + struct sk_buff *skb; + struct can_frame *cf = NULL; + int err; + + err = mcp25xxfd_get_timestamp(priv, ×tamp); + if (err) + return err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_BDIAG1, &bdiag1); + if (err) + return err; + + /* Write 0s to clear error bits, don't write 1s to non active + * bits, as they will be set. + */ + err = regmap_write(priv->map_reg, MCP25XXFD_REG_BDIAG1, 0x0); + if (err) + return err; + + priv->can.can_stats.bus_error++; + + skb = alloc_can_err_skb(priv->ndev, &cf); + if (cf) + cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; + + /* Controller misconfiguration */ + if (WARN_ON(bdiag1 & MCP25XXFD_REG_BDIAG1_DLCMM)) + netdev_err(priv->ndev, + "recv'd DLC is larger than PLSIZE of FIFO element."); + + /* RX errors */ + if (bdiag1 & (MCP25XXFD_REG_BDIAG1_DCRCERR | + MCP25XXFD_REG_BDIAG1_NCRCERR)) { + netdev_dbg(priv->ndev, "CRC error\n"); + + stats->rx_errors++; + if (cf) + cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ; + } + if (bdiag1 & (MCP25XXFD_REG_BDIAG1_DSTUFERR | + MCP25XXFD_REG_BDIAG1_NSTUFERR)) { + netdev_dbg(priv->ndev, "Stuff error\n"); + + stats->rx_errors++; + if (cf) + cf->data[2] |= CAN_ERR_PROT_STUFF; + } + if (bdiag1 & (MCP25XXFD_REG_BDIAG1_DFORMERR | + MCP25XXFD_REG_BDIAG1_NFORMERR)) { + netdev_dbg(priv->ndev, "Format error\n"); + + stats->rx_errors++; + if (cf) + cf->data[2] |= CAN_ERR_PROT_FORM; + } + + /* TX errors */ + if (bdiag1 & MCP25XXFD_REG_BDIAG1_NACKERR) { + netdev_dbg(priv->ndev, "NACK error\n"); + + stats->tx_errors++; + if (cf) { + cf->can_id |= CAN_ERR_ACK; + cf->data[2] |= CAN_ERR_PROT_TX; + } + } + if (bdiag1 & (MCP25XXFD_REG_BDIAG1_DBIT1ERR | + MCP25XXFD_REG_BDIAG1_NBIT1ERR)) { + netdev_dbg(priv->ndev, "Bit1 error\n"); + + stats->tx_errors++; + if (cf) + cf->data[2] |= CAN_ERR_PROT_TX | CAN_ERR_PROT_BIT1; + } + if (bdiag1 & (MCP25XXFD_REG_BDIAG1_DBIT0ERR | + MCP25XXFD_REG_BDIAG1_NBIT0ERR)) { + netdev_dbg(priv->ndev, "Bit0 error\n"); + + stats->tx_errors++; + if (cf) + cf->data[2] |= CAN_ERR_PROT_TX | CAN_ERR_PROT_BIT0; + } + + if (!cf) + return 0; + + err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp); + if (err) + stats->rx_fifo_errors++; + + return 0; +} + +static int mcp25xxfd_handle_cerrif(struct mcp25xxfd_priv *priv) +{ + struct net_device_stats *stats = &priv->ndev->stats; + struct sk_buff *skb; + struct can_frame *cf = NULL; + enum can_state new_state, rx_state, tx_state; + u32 trec, timestamp; + int err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_TREC, &trec); + if (err) + return err; + + if (trec & MCP25XXFD_REG_TREC_TXBO) + tx_state = CAN_STATE_BUS_OFF; + else if (trec & MCP25XXFD_REG_TREC_TXBP) + tx_state = CAN_STATE_ERROR_PASSIVE; + else if (trec & MCP25XXFD_REG_TREC_TXWARN) + tx_state = CAN_STATE_ERROR_WARNING; + else + tx_state = CAN_STATE_ERROR_ACTIVE; + + if (trec & MCP25XXFD_REG_TREC_RXBP) + rx_state = CAN_STATE_ERROR_PASSIVE; + else if (trec & MCP25XXFD_REG_TREC_RXWARN) + rx_state = CAN_STATE_ERROR_WARNING; + else + rx_state = CAN_STATE_ERROR_ACTIVE; + + new_state = max(tx_state, rx_state); + if (new_state == priv->can.state) + return 0; + + /* The skb allocation might fail, but can_change_state() + * handles cf == NULL. + */ + skb = mcp25xxfd_alloc_can_err_skb(priv, &cf, ×tamp); + can_change_state(priv->ndev, cf, tx_state, rx_state); + + if (new_state == CAN_STATE_BUS_OFF) { + /* As we're going to switch off the chip now, let's + * save the error counters and return them to + * userspace, if do_get_berr_counter() is called while + * the chip is in Bus Off. + */ + err = __mcp25xxfd_get_berr_counter(priv->ndev, &priv->bec); + if (err) + return err; + + mcp25xxfd_chip_stop(priv, CAN_STATE_BUS_OFF); + can_bus_off(priv->ndev); + } + + if (!skb) + return 0; + + if (new_state != CAN_STATE_BUS_OFF) { + struct can_berr_counter bec; + + err = mcp25xxfd_get_berr_counter(priv->ndev, &bec); + if (err) + return err; + cf->data[6] = bec.txerr; + cf->data[7] = bec.rxerr; + } + + err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp); + if (err) + stats->rx_fifo_errors++; + + return 0; +} + +static int +mcp25xxfd_handle_modif(const struct mcp25xxfd_priv *priv, bool *set_normal_mode) +{ + const u8 mode_reference = mcp25xxfd_get_normal_mode(priv); + u8 mode; + int err; + + err = mcp25xxfd_chip_get_mode(priv, &mode); + if (err) + return err; + + if (mode == mode_reference) { + netdev_dbg(priv->ndev, + "Controller changed into %s Mode (%u).\n", + mcp25xxfd_get_mode_str(mode), mode); + return 0; + } + + /* According to MCP2517FD errata DS80000792B 1., during a TX + * MAB underflow, the controller will transition to Restricted + * Operation Mode or Listen Only Mode (depending on SERR2LOM). + * + * However this is not always the case. If SERR2LOM is + * configured for Restricted Operation Mode (SERR2LOM not set) + * the MCP2517FD will sometimes transition to Listen Only Mode + * first. When polling this bit we see that it will transition + * to Restricted Operation Mode shortly after. + */ + if ((priv->devtype_data.quirks & MCP25XXFD_QUIRK_MAB_NO_WARN) && + (mode == MCP25XXFD_REG_CON_MODE_RESTRICTED || + mode == MCP25XXFD_REG_CON_MODE_LISTENONLY)) + netdev_dbg(priv->ndev, + "Controller changed into %s Mode (%u).\n", + mcp25xxfd_get_mode_str(mode), mode); + else + netdev_err(priv->ndev, + "Controller changed into %s Mode (%u).\n", + mcp25xxfd_get_mode_str(mode), mode); + + /* After the application requests Normal mode, the Controller + * will automatically attempt to retransmit the message that + * caused the TX MAB underflow. + * + * However, if there is an ECC error in the TX-RAM, we first + * have to reload the tx-object before requesting Normal + * mode. This is done later in mcp25xxfd_handle_eccif(). + */ + if (priv->regs_status.intf & MCP25XXFD_REG_INT_ECCIF) { + *set_normal_mode = true; + return 0; + } + + return mcp25xxfd_chip_set_normal_mode_nowait(priv); +} + +static int mcp25xxfd_handle_serrif(struct mcp25xxfd_priv *priv) +{ + struct mcp25xxfd_ecc *ecc = &priv->ecc; + struct net_device_stats *stats = &priv->ndev->stats; + bool handled = false; + + /* TX MAB underflow + * + * According to MCP2517FD Errata DS80000792B 1. a TX MAB + * underflow is indicated by SERRIF and MODIF. + * + * In addition to the effects mentioned in the Errata, there + * are Bus Errors due to the aborted CAN frame, so a IVMIF + * will be seen as well. + * + * Sometimes there is an ECC error in the TX-RAM, which leads + * to a TX MAB underflow. + * + * However, probably due to a race condition, there is no + * associated MODIF pending. + * + * Further, there are situations, where the SERRIF is caused + * by an ECC error in the TX-RAM, but not even the ECCIF is + * set. This only seems to happen _after_ the first occurrence + * of a ECCIF (which is tracked in ecc->cnt). + * + * Treat all as a known system errors.. + */ + if ((priv->regs_status.intf & MCP25XXFD_REG_INT_MODIF && + priv->regs_status.intf & MCP25XXFD_REG_INT_IVMIF) || + priv->regs_status.intf & MCP25XXFD_REG_INT_ECCIF || + ecc->cnt) { + const char *msg; + + if (priv->regs_status.intf & MCP25XXFD_REG_INT_ECCIF || + ecc->cnt) + msg = "TX MAB underflow due to ECC error detected."; + else + msg = "TX MAB underflow detected."; + + if (priv->devtype_data.quirks & MCP25XXFD_QUIRK_MAB_NO_WARN) + netdev_dbg(priv->ndev, "%s\n", msg); + else + netdev_info(priv->ndev, "%s\n", msg); + + stats->tx_aborted_errors++; + stats->tx_errors++; + handled = true; + } + + /* RX MAB overflow + * + * According to MCP2517FD Errata DS80000792B 1. a RX MAB + * overflow is indicated by SERRIF. + * + * In addition to the effects mentioned in the Errata, (most + * of the times) a RXOVIF is raised, if the FIFO that is being + * received into has the RXOVIE activated (and we have enabled + * RXOVIE on all FIFOs). + * + * Sometimes there is no RXOVIF just a RXIF is pending. + * + * Treat all as a known system errors.. + */ + if (priv->regs_status.intf & MCP25XXFD_REG_INT_RXOVIF || + priv->regs_status.intf & MCP25XXFD_REG_INT_RXIF) { + stats->rx_dropped++; + handled = true; + } + + if (!handled) + netdev_err(priv->ndev, + "Unhandled System Error Interrupt (intf=0x%08x)!\n", + priv->regs_status.intf); + + return 0; +} + +static int +mcp25xxfd_handle_eccif_recover(struct mcp25xxfd_priv *priv, u8 nr) +{ + struct mcp25xxfd_tx_ring *tx_ring = priv->tx; + struct mcp25xxfd_ecc *ecc = &priv->ecc; + struct mcp25xxfd_tx_obj *tx_obj; + u8 chip_tx_tail, tx_tail, offset; + u16 addr; + int err; + + addr = FIELD_GET(MCP25XXFD_REG_ECCSTAT_ERRADDR_MASK, ecc->ecc_stat); + + err = mcp25xxfd_tx_tail_get_from_chip(priv, &chip_tx_tail); + if (err) + return err; + + tx_tail = mcp25xxfd_get_tx_tail(tx_ring); + offset = (nr - chip_tx_tail) & (tx_ring->obj_num - 1); + + /* Bail out if one of the following is met: + * - tx_tail information is inconsistent + * - for mcp2517fd: offset not 0 + * - for mcp2518fd: offset not 0 or 1 + */ + if (chip_tx_tail != tx_tail || + !(offset == 0 || (offset == 1 && mcp25xxfd_is_2518(priv)))) { + netdev_err(priv->ndev, + "ECC Error information inconsistent (addr=0x%04x, nr=%d, tx_tail=0x%08x(%d), chip_tx_tail=%d, offset=%d).\n", + addr, nr, tx_ring->tail, tx_tail, chip_tx_tail, + offset); + return -EINVAL; + } + + netdev_info(priv->ndev, + "Recovering %s ECC Error at address 0x%04x (in TX-RAM, tx_obj=%d, tx_tail=0x%08x(%d), offset=%d).\n", + ecc->ecc_stat & MCP25XXFD_REG_ECCSTAT_SECIF ? + "Single" : "Double", + addr, nr, tx_ring->tail, tx_tail, offset); + + /* reload tx_obj into controller RAM ... */ + tx_obj = &tx_ring->obj[nr]; + err = spi_sync_transfer(priv->spi, tx_obj->xfer, 1); + if (err) + return err; + + /* ... and trigger retransmit */ + return mcp25xxfd_chip_set_normal_mode(priv); +} + +static int +mcp25xxfd_handle_eccif(struct mcp25xxfd_priv *priv, bool set_normal_mode) +{ + struct mcp25xxfd_ecc *ecc = &priv->ecc; + const char *msg; + bool in_tx_ram; + u32 ecc_stat; + u16 addr; + u8 nr; + int err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_ECCSTAT, &ecc_stat); + if (err) + return err; + + err = regmap_update_bits(priv->map_reg, MCP25XXFD_REG_ECCSTAT, + MCP25XXFD_REG_ECCSTAT_IF_MASK, ~ecc_stat); + if (err) + return err; + + /* Check if ECC error occurred in TX-RAM */ + addr = FIELD_GET(MCP25XXFD_REG_ECCSTAT_ERRADDR_MASK, ecc_stat); + err = mcp25xxfd_get_tx_nr_by_addr(priv->tx, &nr, addr); + if (!err) + in_tx_ram = true; + else if (err == -ENOENT) + in_tx_ram = false; + else + return err; + + if (ecc_stat & MCP25XXFD_REG_ECCSTAT_SECIF) + msg = "Single ECC Error corrected at address"; + else if (ecc_stat & MCP25XXFD_REG_ECCSTAT_DEDIF) + msg = "Double ECC Error detected at address"; + else + return -EINVAL; + + if (!in_tx_ram) { + ecc->ecc_stat = 0; + + if (ecc_stat & MCP25XXFD_REG_ECCSTAT_SECIF) + netdev_info(priv->ndev, "%s 0x%04x.\n", + msg, addr); + else + netdev_notice(priv->ndev, "%s 0x%04x.\n", + msg, addr); + } else { + /* Re-occurring error? */ + if (ecc->ecc_stat == ecc_stat) { + ecc->cnt++; + } else { + ecc->ecc_stat = ecc_stat; + ecc->cnt = 1; + } + + netdev_info(priv->ndev, + "%s 0x%04x (in TX-RAM, tx_obj=%d), occurred %d time%s.\n", + msg, addr, nr, ecc->cnt, ecc->cnt > 1 ? "s" : ""); + + if (ecc->cnt >= MCP25XXFD_ECC_CNT_MAX) + return mcp25xxfd_handle_eccif_recover(priv, nr); + } + + if (set_normal_mode) + return mcp25xxfd_chip_set_normal_mode_nowait(priv); + + return 0; +} + +static int mcp25xxfd_handle_spicrcif(struct mcp25xxfd_priv *priv) +{ + int err; + u32 crc; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_CRC, &crc); + if (err) + return err; + + err = regmap_update_bits(priv->map_reg, MCP25XXFD_REG_CRC, + MCP25XXFD_REG_CRC_IF_MASK, + ~crc); + if (err) + return err; + + if (crc & MCP25XXFD_REG_CRC_FERRIF) + netdev_notice(priv->ndev, "CRC write command format error.\n"); + else if (crc & MCP25XXFD_REG_CRC_CRCERRIF) + netdev_notice(priv->ndev, + "CRC write error detected. CRC=0x%04lx.\n", + FIELD_GET(MCP25XXFD_REG_CRC_MASK, crc)); + + return 0; +} + +#define mcp25xxfd_handle(priv, irq, ...) \ +({ \ + struct mcp25xxfd_priv *_priv = (priv); \ + int err; \ +\ + err = mcp25xxfd_handle_##irq(_priv, ## __VA_ARGS__); \ + if (err) \ + netdev_err(_priv->ndev, \ + "IRQ handler mcp25xxfd_handle_%s() returned %d.\n", \ + __stringify(irq), err); \ + err; \ +}) + +static irqreturn_t mcp25xxfd_irq(int irq, void *dev_id) +{ + struct mcp25xxfd_priv *priv = dev_id; + irqreturn_t handled = IRQ_NONE; + int err; + + if (priv->rx_int) + do { + int rx_pending; + + rx_pending = gpiod_get_value_cansleep(priv->rx_int); + if (!rx_pending) + break; + + err = mcp25xxfd_handle(priv, rxif); + if (err) + goto out_fail; + + handled = IRQ_HANDLED; + } while (1); + + do { + u32 intf_pending, intf_pending_clearable; + bool set_normal_mode; + + err = regmap_bulk_read(priv->map_reg, MCP25XXFD_REG_INT, + &priv->regs_status, + sizeof(priv->regs_status) / + sizeof(u32)); + if (err) + goto out_fail; + + intf_pending = FIELD_GET(MCP25XXFD_REG_INT_IF_MASK, + priv->regs_status.intf) & + FIELD_GET(MCP25XXFD_REG_INT_IE_MASK, + priv->regs_status.intf); + + if (!(intf_pending)) + return handled; + + /* Some interrupts must be ACKed in the + * MCP25XXFD_REG_INT register. + * - First ACK then handle, to avoid lost-IRQ race + * condition on fast re-occurring interrupts. + * - Write "0" to clear active IRQs, "1" to all other, + * to avoid r/m/w race condition on the + * MCP25XXFD_REG_INT register. + */ + intf_pending_clearable = intf_pending & + MCP25XXFD_REG_INT_IF_CLEARABLE_MASK; + if (intf_pending_clearable) { + err = regmap_update_bits(priv->map_reg, + MCP25XXFD_REG_INT, + MCP25XXFD_REG_INT_IF_MASK, + ~intf_pending_clearable); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_MODIF) { + err = mcp25xxfd_handle(priv, modif, &set_normal_mode); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_RXIF) { + err = mcp25xxfd_handle(priv, rxif); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_TEFIF) { + err = mcp25xxfd_handle(priv, tefif); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_RXOVIF) { + err = mcp25xxfd_handle(priv, rxovif); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_TXATIF) { + err = mcp25xxfd_handle(priv, txatif); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_IVMIF) { + err = mcp25xxfd_handle(priv, ivmif); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_SERRIF) { + err = mcp25xxfd_handle(priv, serrif); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_ECCIF) { + err = mcp25xxfd_handle(priv, eccif, set_normal_mode); + if (err) + goto out_fail; + } + + if (intf_pending & MCP25XXFD_REG_INT_SPICRCIF) { + err = mcp25xxfd_handle(priv, spicrcif); + if (err) + goto out_fail; + } + + /* On the MCP2527FD and MCP2518FD, we don't get a + * CERRIF IRQ on the transition TX ERROR_WARNING -> TX + * ERROR_ACTIVE. + */ + if (intf_pending & MCP25XXFD_REG_INT_CERRIF || + priv->can.state > CAN_STATE_ERROR_ACTIVE) { + err = mcp25xxfd_handle(priv, cerrif); + if (err) + goto out_fail; + + /* In Bus Off we completely shut down the + * controller. Every subsequent register read + * will read bogus data, and if + * MCP25XXFD_QUIRK_CRC_REG is enabled the CRC + * check will fail, too. So leave IRQ handler + * directly. + */ + if (priv->can.state == CAN_STATE_BUS_OFF) + return IRQ_HANDLED; + } + + handled = IRQ_HANDLED; + } while (1); + + out_fail: + netdev_err(priv->ndev, "IRQ handler returned %d (intf=0x%08x).\n", + err, priv->regs_status.intf); + mcp25xxfd_chip_interrupts_disable(priv); + + return handled; +} + +static inline struct +mcp25xxfd_tx_obj *mcp25xxfd_get_tx_obj_next(struct mcp25xxfd_tx_ring *tx_ring) +{ + u8 tx_head; + + tx_head = mcp25xxfd_get_tx_head(tx_ring); + + return &tx_ring->obj[tx_head]; +} + +static void +mcp25xxfd_tx_obj_from_skb(const struct mcp25xxfd_priv *priv, + struct mcp25xxfd_tx_obj *tx_obj, + const struct sk_buff *skb, + unsigned int seq) +{ + const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; + struct mcp25xxfd_hw_tx_obj_raw *hw_tx_obj; + union mcp25xxfd_tx_obj_load_buf *load_buf; + u8 dlc; + u32 id, flags; + int offset, len; + + if (cfd->can_id & CAN_EFF_FLAG) { + u32 sid, eid; + + sid = FIELD_GET(MCP25XXFD_REG_FRAME_EFF_SID_MASK, cfd->can_id); + eid = FIELD_GET(MCP25XXFD_REG_FRAME_EFF_EID_MASK, cfd->can_id); + + id = FIELD_PREP(MCP25XXFD_OBJ_ID_EID_MASK, eid) | + FIELD_PREP(MCP25XXFD_OBJ_ID_SID_MASK, sid); + + flags = MCP25XXFD_OBJ_FLAGS_IDE; + } else { + id = FIELD_PREP(MCP25XXFD_OBJ_ID_SID_MASK, cfd->can_id); + flags = 0; + } + + /* Use the MCP2518FD mask even on the MCP2517FD. It doesn't + * harm, only the lower 7 bits will be transferred into the + * TEF object. + */ + dlc = can_len2dlc(cfd->len); + flags |= FIELD_PREP(MCP25XXFD_OBJ_FLAGS_SEQ_MCP2518FD_MASK, seq) | + FIELD_PREP(MCP25XXFD_OBJ_FLAGS_DLC, dlc); + + if (cfd->can_id & CAN_RTR_FLAG) + flags |= MCP25XXFD_OBJ_FLAGS_RTR; + + /* CANFD */ + if (can_is_canfd_skb(skb)) { + if (cfd->flags & CANFD_ESI) + flags |= MCP25XXFD_OBJ_FLAGS_ESI; + + flags |= MCP25XXFD_OBJ_FLAGS_FDF; + + if (cfd->flags & CANFD_BRS) + flags |= MCP25XXFD_OBJ_FLAGS_BRS; + } + + load_buf = &tx_obj->buf; + if (priv->devtype_data.quirks & MCP25XXFD_QUIRK_CRC_TX) + hw_tx_obj = &load_buf->crc.hw_tx_obj; + else + hw_tx_obj = &load_buf->nocrc.hw_tx_obj; + + put_unaligned_le32(id, &hw_tx_obj->id); + put_unaligned_le32(flags, &hw_tx_obj->flags); + + /* Clear data at end of CAN frame */ + // FIXME: what does the controller send in CANFD if can_dlc2len(can_len2dlc(cfd->len)) > cfd->len? + offset = round_down(cfd->len, sizeof(u32)); + len = round_up(can_dlc2len(dlc), sizeof(u32)) - offset; + if (len) + memset(hw_tx_obj->data + offset, 0x0, len); + memcpy(hw_tx_obj->data, cfd->data, cfd->len); + + /* Number of bytes to be written into the RAM of the controller */ + len = sizeof(hw_tx_obj->id) + sizeof(hw_tx_obj->flags); + len += round_up(cfd->len, sizeof(u32)); + + if (priv->devtype_data.quirks & MCP25XXFD_QUIRK_CRC_TX) { + u16 crc; + + mcp25xxfd_spi_cmd_crc_set_len_in_ram(&load_buf->crc.cmd, + len); + /* CRC */ + len += sizeof(load_buf->crc.cmd); + crc = mcp25xxfd_crc16_compute(&load_buf->crc, len); + put_unaligned_be16(crc, (void *)load_buf + len); + + /* Total length */ + len += sizeof(load_buf->crc.crc); + } else { + len += sizeof(load_buf->nocrc.cmd); + } + + tx_obj->xfer[0].len = len; +} + +static int mcp25xxfd_tx_obj_write(const struct mcp25xxfd_priv *priv, + struct mcp25xxfd_tx_obj *tx_obj) +{ + return spi_async(priv->spi, &tx_obj->msg); +} + +static netdev_tx_t mcp25xxfd_start_xmit(struct sk_buff *skb, + struct net_device *ndev) +{ + struct mcp25xxfd_priv *priv = netdev_priv(ndev); + struct mcp25xxfd_tx_ring *tx_ring = priv->tx; + struct mcp25xxfd_tx_obj *tx_obj; + u8 tx_head; + int err; + + if (can_dropped_invalid_skb(ndev, skb)) + return NETDEV_TX_OK; + + if (tx_ring->head - tx_ring->tail >= tx_ring->obj_num) { + netdev_dbg(priv->ndev, + "Stopping tx-queue (tx_head=0x%08x, tx_tail=0x%08x, len=%d).\n", + tx_ring->head, tx_ring->tail, + tx_ring->head - tx_ring->tail); + + netif_stop_queue(ndev); + + return NETDEV_TX_BUSY; + } + + tx_obj = mcp25xxfd_get_tx_obj_next(tx_ring); + mcp25xxfd_tx_obj_from_skb(priv, tx_obj, skb, tx_ring->head); + + /* Stop queue if we occupy the complete TX FIFO */ + tx_head = mcp25xxfd_get_tx_head(tx_ring); + tx_ring->head++; + if (tx_ring->head - tx_ring->tail >= tx_ring->obj_num) + netif_stop_queue(ndev); + + can_put_echo_skb(skb, ndev, tx_head); + + err = mcp25xxfd_tx_obj_write(priv, tx_obj); + if (err) + goto out_err; + + return NETDEV_TX_OK; + + out_err: + netdev_err(priv->ndev, "ERROR in %s: %d\n", __func__, err); + + return NETDEV_TX_OK; +} + +static int mcp25xxfd_open(struct net_device *ndev) +{ + struct mcp25xxfd_priv *priv = netdev_priv(ndev); + const struct spi_device *spi = priv->spi; + int err; + + err = pm_runtime_get_sync(ndev->dev.parent); + if (err < 0) { + pm_runtime_put_noidle(ndev->dev.parent); + return err; + } + + err = open_candev(ndev); + if (err) + goto out_pm_runtime_put; + + err = mcp25xxfd_ring_alloc(priv); + if (err) + goto out_close_candev; + + err = mcp25xxfd_transceiver_enable(priv); + if (err) + goto out_mcp25xxfd_ring_free; + + err = mcp25xxfd_chip_start(priv); + if (err) + goto out_transceiver_disable; + + can_rx_offload_enable(&priv->offload); + + err = request_threaded_irq(spi->irq, NULL, mcp25xxfd_irq, + IRQF_ONESHOT, dev_name(&spi->dev), + priv); + if (err) + goto out_can_rx_offload_disable; + + err = mcp25xxfd_chip_interrupts_enable(priv); + if (err) + goto out_free_irq; + + netif_start_queue(ndev); + + return 0; + + out_free_irq: + free_irq(spi->irq, priv); + out_can_rx_offload_disable: + can_rx_offload_disable(&priv->offload); + out_transceiver_disable: + mcp25xxfd_transceiver_disable(priv); + out_mcp25xxfd_ring_free: + mcp25xxfd_ring_free(priv); + out_close_candev: + close_candev(ndev); + out_pm_runtime_put: + mcp25xxfd_chip_stop(priv, CAN_STATE_STOPPED); + pm_runtime_put(ndev->dev.parent); + + return err; +} + +static int mcp25xxfd_stop(struct net_device *ndev) +{ + struct mcp25xxfd_priv *priv = netdev_priv(ndev); + + netif_stop_queue(ndev); + mcp25xxfd_chip_interrupts_disable(priv); + free_irq(ndev->irq, priv); + can_rx_offload_disable(&priv->offload); + mcp25xxfd_chip_stop(priv, CAN_STATE_STOPPED); + mcp25xxfd_transceiver_disable(priv); + mcp25xxfd_ring_free(priv); + close_candev(ndev); + + pm_runtime_put(ndev->dev.parent); + + return 0; +} + +static const struct net_device_ops mcp25xxfd_netdev_ops = { + .ndo_open = mcp25xxfd_open, + .ndo_stop = mcp25xxfd_stop, + .ndo_start_xmit = mcp25xxfd_start_xmit, + .ndo_change_mtu = can_change_mtu, +}; + +static void +mcp25xxfd_register_quirks(struct mcp25xxfd_priv *priv) +{ + const struct spi_device *spi = priv->spi; + const struct spi_controller *ctlr = spi->controller; + + if (ctlr->flags & SPI_CONTROLLER_HALF_DUPLEX) + priv->devtype_data.quirks |= MCP25XXFD_QUIRK_HALF_DUPLEX; +} + +static int mcp25xxfd_register_chip_detect(struct mcp25xxfd_priv *priv) +{ + const struct net_device *ndev = priv->ndev; + const struct mcp25xxfd_devtype_data *devtype_data; + u32 osc; + int err; + + /* The OSC_LPMEN is only supported on MCP2518FD, so use it to + * autodetect the model. + */ + err = regmap_update_bits(priv->map_reg, MCP25XXFD_REG_OSC, + MCP25XXFD_REG_OSC_LPMEN, + MCP25XXFD_REG_OSC_LPMEN); + if (err) + return err; + + err = regmap_read(priv->map_reg, MCP25XXFD_REG_OSC, &osc); + if (err) + return err; + + if (osc & MCP25XXFD_REG_OSC_LPMEN) + devtype_data = &mcp25xxfd_devtype_data_mcp2518fd; + else + devtype_data = &mcp25xxfd_devtype_data_mcp2517fd; + + if (!mcp25xxfd_is_25XX(priv) && + priv->devtype_data.model != devtype_data->model) { + netdev_info(ndev, + "Detected %s, but firmware specifies a %s. Fixing up.", + __mcp25xxfd_get_model_str(devtype_data->model), + mcp25xxfd_get_model_str(priv)); + } + priv->devtype_data = *devtype_data; + + /* We need to preserve the Half Duplex Quirk. */ + mcp25xxfd_register_quirks(priv); + + /* Re-init regmap with quirks of detected model. */ + return mcp25xxfd_regmap_init(priv); +} + +static int mcp25xxfd_register_check_rx_int(struct mcp25xxfd_priv *priv) +{ + int err, rx_pending; + + if (!priv->rx_int) + return 0; + + err = mcp25xxfd_chip_rx_int_enable(priv); + if (err) + return err; + + /* Check if RX_INT is properly working. The RX_INT should not + * be active after a softreset. + */ + rx_pending = gpiod_get_value_cansleep(priv->rx_int); + + err = mcp25xxfd_chip_rx_int_disable(priv); + if (err) + return err; + + if (!rx_pending) + return 0; + + netdev_info(priv->ndev, + "RX_INT active after softreset, disabling RX_INT support."); + devm_gpiod_put(&priv->spi->dev, priv->rx_int); + priv->rx_int = NULL; + + return 0; +} + +static int +mcp25xxfd_register_get_dev_id(const struct mcp25xxfd_priv *priv, + u32 *dev_id, u32 *effective_speed_hz) +{ + struct mcp25xxfd_map_buf_nocrc *buf_rx; + struct mcp25xxfd_map_buf_nocrc *buf_tx; + struct spi_transfer xfer[2] = { }; + int err; + + buf_rx = kzalloc(sizeof(*buf_rx), GFP_KERNEL); + if (!buf_rx) + return -ENOMEM; + + buf_tx = kzalloc(sizeof(*buf_tx), GFP_KERNEL); + if (!buf_tx) { + err = -ENOMEM; + goto out_kfree_buf_rx; + } + + xfer[0].tx_buf = buf_tx; + xfer[0].len = sizeof(buf_tx->cmd); + xfer[1].rx_buf = buf_rx->data; + xfer[1].len = sizeof(dev_id); + + mcp25xxfd_spi_cmd_read_nocrc(&buf_tx->cmd, MCP25XXFD_REG_DEVID); + err = spi_sync_transfer(priv->spi, xfer, ARRAY_SIZE(xfer)); + if (err) + goto out_kfree_buf_tx; + + *dev_id = be32_to_cpup((__be32 *)buf_rx->data); + *effective_speed_hz = xfer->effective_speed_hz; + + out_kfree_buf_tx: + kfree(buf_tx); + out_kfree_buf_rx: + kfree(buf_rx); + + return 0; +} + +#define MCP25XXFD_QUIRK_ACTIVE(quirk) \ + (priv->devtype_data.quirks & MCP25XXFD_QUIRK_##quirk ? '+' : '-') + +static int +mcp25xxfd_register_done(const struct mcp25xxfd_priv *priv) +{ + u32 dev_id, effective_speed_hz; + int err; + + err = mcp25xxfd_register_get_dev_id(priv, &dev_id, + &effective_speed_hz); + if (err) + return err; + + netdev_info(priv->ndev, + "%s rev%lu.%lu (%cRX_INT %cMAB_NO_WARN %cCRC_REG %cCRC_RX %cCRC_TX %cECC %cHD m:%u.%02uMHz r:%u.%02uMHz e:%u.%02uMHz) successfully initialized.\n", + mcp25xxfd_get_model_str(priv), + FIELD_GET(MCP25XXFD_REG_DEVID_ID_MASK, dev_id), + FIELD_GET(MCP25XXFD_REG_DEVID_REV_MASK, dev_id), + priv->rx_int ? '+' : '-', + MCP25XXFD_QUIRK_ACTIVE(MAB_NO_WARN), + MCP25XXFD_QUIRK_ACTIVE(CRC_REG), + MCP25XXFD_QUIRK_ACTIVE(CRC_RX), + MCP25XXFD_QUIRK_ACTIVE(CRC_TX), + MCP25XXFD_QUIRK_ACTIVE(ECC), + MCP25XXFD_QUIRK_ACTIVE(HALF_DUPLEX), + priv->spi_max_speed_hz_orig / 1000000, + priv->spi_max_speed_hz_orig % 1000000 / 1000 / 10, + priv->spi->max_speed_hz / 1000000, + priv->spi->max_speed_hz % 1000000 / 1000 / 10, + effective_speed_hz / 1000000, + effective_speed_hz % 1000000 / 1000 / 10); + + return 0; +} + +static int mcp25xxfd_register(struct mcp25xxfd_priv *priv) +{ + struct net_device *ndev = priv->ndev; + int err; + + err = mcp25xxfd_clks_and_vdd_enable(priv); + if (err) + return err; + + pm_runtime_get_noresume(ndev->dev.parent); + err = pm_runtime_set_active(ndev->dev.parent); + if (err) + goto out_runtime_put_noidle; + pm_runtime_enable(ndev->dev.parent); + + mcp25xxfd_register_quirks(priv); + + err = mcp25xxfd_chip_softreset(priv); + if (err == -ENODEV) + goto out_runtime_disable; + if (err) + goto out_chip_set_mode_sleep; + + err = mcp25xxfd_register_chip_detect(priv); + if (err) + goto out_chip_set_mode_sleep; + + err = mcp25xxfd_register_check_rx_int(priv); + if (err) + goto out_chip_set_mode_sleep; + + err = register_candev(ndev); + if (err) + goto out_chip_set_mode_sleep; + + err = mcp25xxfd_register_done(priv); + if (err) + goto out_unregister_candev; + + /* Put controller into sleep mode and let pm_runtime_put() + * disable the clocks and vdd. If CONFIG_PM is not enabled, + * the clocks and vdd will stay powered. + */ + err = mcp25xxfd_chip_set_mode(priv, MCP25XXFD_REG_CON_MODE_SLEEP); + if (err) + goto out_unregister_candev; + + pm_runtime_put(ndev->dev.parent); + + return 0; + + out_unregister_candev: + unregister_candev(ndev); + out_chip_set_mode_sleep: + mcp25xxfd_chip_set_mode(priv, MCP25XXFD_REG_CON_MODE_SLEEP); + out_runtime_disable: + pm_runtime_disable(ndev->dev.parent); + out_runtime_put_noidle: + pm_runtime_put_noidle(ndev->dev.parent); + mcp25xxfd_clks_and_vdd_disable(priv); + + return err; +} + +static inline void mcp25xxfd_unregister(struct mcp25xxfd_priv *priv) +{ + struct net_device *ndev = priv->ndev; + + unregister_candev(ndev); + + pm_runtime_get_sync(ndev->dev.parent); + pm_runtime_put_noidle(ndev->dev.parent); + mcp25xxfd_clks_and_vdd_disable(priv); + pm_runtime_disable(ndev->dev.parent); +} + +static const struct of_device_id mcp25xxfd_of_match[] = { + { + .compatible = "microchip,mcp2517fd", + .data = &mcp25xxfd_devtype_data_mcp2517fd, + }, { + .compatible = "microchip,mcp2518fd", + .data = &mcp25xxfd_devtype_data_mcp2518fd, + }, { + .compatible = "microchip,mcp25xxfd", + .data = &mcp25xxfd_devtype_data_mcp25xxfd, + }, { + /* sentinel */ + }, +}; +MODULE_DEVICE_TABLE(of, mcp25xxfd_of_match); + +static const struct spi_device_id mcp25xxfd_id_table[] = { + { + .name = "mcp2517fd", + .driver_data = (kernel_ulong_t)&mcp25xxfd_devtype_data_mcp2517fd, + }, { + .name = "mcp2518fd", + .driver_data = (kernel_ulong_t)&mcp25xxfd_devtype_data_mcp2518fd, + }, { + .name = "mcp25xxfd", + .driver_data = (kernel_ulong_t)&mcp25xxfd_devtype_data_mcp25xxfd, + }, { + /* sentinel */ + }, +}; +MODULE_DEVICE_TABLE(spi, mcp25xxfd_id_table); + +static int mcp25xxfd_probe(struct spi_device *spi) +{ + const void *match; + struct net_device *ndev; + struct mcp25xxfd_priv *priv; + struct gpio_desc *rx_int; + struct regulator *reg_vdd, *reg_xceiver; + struct clk *clk; + u32 freq; + int err; + + rx_int = devm_gpiod_get_optional(&spi->dev, "microchip,rx-int", + GPIOD_IN); + if (PTR_ERR(rx_int) == -EPROBE_DEFER) + return -EPROBE_DEFER; + else if (IS_ERR(rx_int)) + return PTR_ERR(rx_int); + + reg_vdd = devm_regulator_get_optional(&spi->dev, "vdd"); + if (PTR_ERR(reg_vdd) == -EPROBE_DEFER) + return -EPROBE_DEFER; + else if (PTR_ERR(reg_vdd) == -ENODEV) + reg_vdd = NULL; + else if (IS_ERR(reg_vdd)) + return PTR_ERR(reg_vdd); + + reg_xceiver = devm_regulator_get_optional(&spi->dev, "xceiver"); + if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER) + return -EPROBE_DEFER; + else if (PTR_ERR(reg_xceiver) == -ENODEV) + reg_xceiver = NULL; + else if (IS_ERR(reg_xceiver)) + return PTR_ERR(reg_xceiver); + + clk = devm_clk_get(&spi->dev, NULL); + if (IS_ERR(clk)) { + dev_err(&spi->dev, "No Oscillator (clock) defined.\n"); + return PTR_ERR(clk); + } + freq = clk_get_rate(clk); + + /* Sanity check */ + if (freq < MCP25XXFD_SYSCLOCK_HZ_MIN || + freq > MCP25XXFD_SYSCLOCK_HZ_MAX) { + dev_err(&spi->dev, + "Oscillator frequency (%u Hz) is too low or high.\n", + freq); + return -ERANGE; + } + + if (freq <= MCP25XXFD_SYSCLOCK_HZ_MAX / MCP25XXFD_OSC_PLL_MULTIPLIER) { + dev_err(&spi->dev, + "Oscillator frequency (%u Hz) is too low and PLL is not supported.\n", + freq); + return -ERANGE; + } + + ndev = alloc_candev(sizeof(struct mcp25xxfd_priv), + MCP25XXFD_TX_OBJ_NUM_MAX); + if (!ndev) + return -ENOMEM; + + SET_NETDEV_DEV(ndev, &spi->dev); + + ndev->netdev_ops = &mcp25xxfd_netdev_ops; + ndev->irq = spi->irq; + ndev->flags |= IFF_ECHO; + + priv = netdev_priv(ndev); + spi_set_drvdata(spi, priv); + priv->can.clock.freq = freq; + priv->can.do_set_mode = mcp25xxfd_set_mode; + priv->can.do_get_berr_counter = mcp25xxfd_get_berr_counter; + priv->can.bittiming_const = &mcp25xxfd_bittiming_const; + priv->can.data_bittiming_const = &mcp25xxfd_data_bittiming_const; + priv->can.ctrlmode_supported = CAN_CTRLMODE_BERR_REPORTING | + CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO; + priv->ndev = ndev; + priv->spi = spi; + priv->rx_int = rx_int; + priv->clk = clk; + priv->reg_vdd = reg_vdd; + priv->reg_xceiver = reg_xceiver; + + match = device_get_match_data(&spi->dev); + if (match) + priv->devtype_data = *(struct mcp25xxfd_devtype_data *)match; + else + priv->devtype_data = *(struct mcp25xxfd_devtype_data *) + spi_get_device_id(spi)->driver_data; + + /* According to the datasheet the SPI clock must be less or + * equal SYSCLOCK / 2. + * + * It turns out, that the Controller is not stable at this + * rate. Known good and bad combinations are: + * + * MCP ext-clk SoC SPI SPI-clk max-clk parent-clk Status config + * + * 2518 20 MHz allwinner,sun8i-h3 allwinner,sun8i-h3-spi 9090909 Hz 90.90% 600000000 Hz good assigned-clocks = <&ccu CLK_SPIx> + * 2518 20 MHz allwinner,sun8i-h3 allwinner,sun8i-h3-spi 9375000 Hz 93.75% 600000000 Hz bad assigned-clocks = <&ccu CLK_SPIx> + * 2518 40 MHz allwinner,sun8i-h3 allwinner,sun8i-h3-spi 17647058 Hz 88.24% 600000000 Hz good assigned-clocks = <&ccu CLK_SPIx> + * 2518 40 MHz allwinner,sun8i-h3 allwinner,sun8i-h3-spi 18750000 Hz 93.75% 600000000 Hz bad assigned-clocks = <&ccu CLK_SPIx> + * 2517 20 MHz fsl,imx8mm fsl,imx51-ecspi 9090909 Hz 90.09% 18181819 Hz good assigned-clocks = <&clk IMX8MM_CLK_ECSPIx_ROOT> + * 2517 20 MHz fsl,imx8mm fsl,imx51-ecspi 9523809 Hz 95.34% 28571429 Hz bad assigned-clocks = <&clk IMX8MM_CLK_ECSPIx_ROOT> + * + * Limit SPI clock to 92.5% of SYSCLOCK / 2 for now. + */ + priv->spi_max_speed_hz_orig = spi->max_speed_hz; + spi->max_speed_hz = min(spi->max_speed_hz, freq / 2 / 1000 * 925); + spi->bits_per_word = 8; + spi->rt = true; + err = spi_setup(spi); + if (err) + goto out_free_candev; + + err = mcp25xxfd_regmap_init(priv); + if (err) + goto out_free_candev; + + err = can_rx_offload_add_manual(ndev, &priv->offload, + MCP25XXFD_NAPI_WEIGHT); + if (err) + goto out_free_candev; + + err = mcp25xxfd_register(priv); + if (err) + goto out_free_candev; + + return 0; + + out_free_candev: + spi->max_speed_hz = priv->spi_max_speed_hz_orig; + + free_candev(ndev); + + return err; +} + +static int mcp25xxfd_remove(struct spi_device *spi) +{ + struct mcp25xxfd_priv *priv = spi_get_drvdata(spi); + struct net_device *ndev = priv->ndev; + + can_rx_offload_del(&priv->offload); + mcp25xxfd_unregister(priv); + spi->max_speed_hz = priv->spi_max_speed_hz_orig; + free_candev(ndev); + + return 0; +} + +static int __maybe_unused mcp25xxfd_runtime_suspend(struct device *device) +{ + const struct mcp25xxfd_priv *priv = dev_get_drvdata(device); + + return mcp25xxfd_clks_and_vdd_disable(priv); +} + +static int __maybe_unused mcp25xxfd_runtime_resume(struct device *device) +{ + const struct mcp25xxfd_priv *priv = dev_get_drvdata(device); + + return mcp25xxfd_clks_and_vdd_enable(priv); +} + +static const struct dev_pm_ops mcp25xxfd_pm_ops = { + SET_RUNTIME_PM_OPS(mcp25xxfd_runtime_suspend, + mcp25xxfd_runtime_resume, NULL) +}; + +static struct spi_driver mcp25xxfd_driver = { + .driver = { + .name = DEVICE_NAME, + .pm = &mcp25xxfd_pm_ops, + .of_match_table = mcp25xxfd_of_match, + }, + .probe = mcp25xxfd_probe, + .remove = mcp25xxfd_remove, + .id_table = mcp25xxfd_id_table, +}; +module_spi_driver(mcp25xxfd_driver); + +MODULE_AUTHOR("Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Microchip MCP25xxFD Family CAN controller driver"); +MODULE_LICENSE("GPL v2"); -- 2.17.1