diff options
Diffstat (limited to 'drivers/net/can/rockchip/rockchip_canfd-rx.c')
| -rw-r--r-- | drivers/net/can/rockchip/rockchip_canfd-rx.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/drivers/net/can/rockchip/rockchip_canfd-rx.c b/drivers/net/can/rockchip/rockchip_canfd-rx.c new file mode 100644 index 000000000000..475c0409e215 --- /dev/null +++ b/drivers/net/can/rockchip/rockchip_canfd-rx.c @@ -0,0 +1,299 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (c) 2023, 2024 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// + +#include <net/netdev_queues.h> + +#include "rockchip_canfd.h" + +static bool rkcanfd_can_frame_header_equal(const struct canfd_frame *const cfd1, + const struct canfd_frame *const cfd2, + const bool is_canfd) +{ + const u8 mask_flags = CANFD_BRS | CANFD_ESI | CANFD_FDF; + canid_t mask = CAN_EFF_FLAG; + + if (canfd_sanitize_len(cfd1->len) != canfd_sanitize_len(cfd2->len)) + return false; + + if (!is_canfd) + mask |= CAN_RTR_FLAG; + + if (cfd1->can_id & CAN_EFF_FLAG) + mask |= CAN_EFF_MASK; + else + mask |= CAN_SFF_MASK; + + if ((cfd1->can_id & mask) != (cfd2->can_id & mask)) + return false; + + if (is_canfd && + (cfd1->flags & mask_flags) != (cfd2->flags & mask_flags)) + return false; + + return true; +} + +static bool rkcanfd_can_frame_data_equal(const struct canfd_frame *cfd1, + const struct canfd_frame *cfd2, + const bool is_canfd) +{ + u8 len; + + if (!is_canfd && (cfd1->can_id & CAN_RTR_FLAG)) + return true; + + len = canfd_sanitize_len(cfd1->len); + + return !memcmp(cfd1->data, cfd2->data, len); +} + +static unsigned int +rkcanfd_fifo_header_to_cfd_header(const struct rkcanfd_priv *priv, + const struct rkcanfd_fifo_header *header, + struct canfd_frame *cfd) +{ + unsigned int len = sizeof(*cfd) - sizeof(cfd->data); + u8 dlc; + + if (header->frameinfo & RKCANFD_REG_FD_FRAMEINFO_FRAME_FORMAT) + cfd->can_id = FIELD_GET(RKCANFD_REG_FD_ID_EFF, header->id) | + CAN_EFF_FLAG; + else + cfd->can_id = FIELD_GET(RKCANFD_REG_FD_ID_SFF, header->id); + + dlc = FIELD_GET(RKCANFD_REG_FD_FRAMEINFO_DATA_LENGTH, + header->frameinfo); + + /* CAN-FD */ + if (header->frameinfo & RKCANFD_REG_FD_FRAMEINFO_FDF) { + cfd->len = can_fd_dlc2len(dlc); + + /* The cfd is not allocated by alloc_canfd_skb(), so + * set CANFD_FDF here. + */ + cfd->flags |= CANFD_FDF; + + if (header->frameinfo & RKCANFD_REG_FD_FRAMEINFO_BRS) + cfd->flags |= CANFD_BRS; + } else { + cfd->len = can_cc_dlc2len(dlc); + + if (header->frameinfo & RKCANFD_REG_FD_FRAMEINFO_RTR) { + cfd->can_id |= CAN_RTR_FLAG; + + return len; + } + } + + return len + cfd->len; +} + +static int rkcanfd_rxstx_filter(struct rkcanfd_priv *priv, + const struct canfd_frame *cfd_rx, const u32 ts, + bool *tx_done) +{ + struct net_device_stats *stats = &priv->ndev->stats; + struct rkcanfd_stats *rkcanfd_stats = &priv->stats; + const struct canfd_frame *cfd_nominal; + const struct sk_buff *skb; + unsigned int tx_tail; + + tx_tail = rkcanfd_get_tx_tail(priv); + skb = priv->can.echo_skb[tx_tail]; + if (!skb) { + netdev_err(priv->ndev, + "%s: echo_skb[%u]=NULL tx_head=0x%08x tx_tail=0x%08x\n", + __func__, tx_tail, + priv->tx_head, priv->tx_tail); + + return -ENOMSG; + } + cfd_nominal = (struct canfd_frame *)skb->data; + + /* We RX'ed a frame identical to our pending TX frame. */ + if (rkcanfd_can_frame_header_equal(cfd_rx, cfd_nominal, + cfd_rx->flags & CANFD_FDF) && + rkcanfd_can_frame_data_equal(cfd_rx, cfd_nominal, + cfd_rx->flags & CANFD_FDF)) { + unsigned int frame_len; + + rkcanfd_handle_tx_done_one(priv, ts, &frame_len); + + WRITE_ONCE(priv->tx_tail, priv->tx_tail + 1); + netif_subqueue_completed_wake(priv->ndev, 0, 1, frame_len, + rkcanfd_get_effective_tx_free(priv), + RKCANFD_TX_START_THRESHOLD); + + *tx_done = true; + + return 0; + } + + if (!(priv->devtype_data.quirks & RKCANFD_QUIRK_RK3568_ERRATUM_6)) + return 0; + + /* Erratum 6: Extended frames may be send as standard frames. + * + * Not affected if: + * - TX'ed a standard frame -or- + * - RX'ed an extended frame + */ + if (!(cfd_nominal->can_id & CAN_EFF_FLAG) || + (cfd_rx->can_id & CAN_EFF_FLAG)) + return 0; + + /* Not affected if: + * - standard part and RTR flag of the TX'ed frame + * is not equal the CAN-ID and RTR flag of the RX'ed frame. + */ + if ((cfd_nominal->can_id & (CAN_RTR_FLAG | CAN_SFF_MASK)) != + (cfd_rx->can_id & (CAN_RTR_FLAG | CAN_SFF_MASK))) + return 0; + + /* Not affected if: + * - length is not the same + */ + if (cfd_nominal->len != cfd_rx->len) + return 0; + + /* Not affected if: + * - the data of non RTR frames is different + */ + if (!(cfd_nominal->can_id & CAN_RTR_FLAG) && + memcmp(cfd_nominal->data, cfd_rx->data, cfd_nominal->len)) + return 0; + + /* Affected by Erratum 6 */ + u64_stats_update_begin(&rkcanfd_stats->syncp); + u64_stats_inc(&rkcanfd_stats->tx_extended_as_standard_errors); + u64_stats_update_end(&rkcanfd_stats->syncp); + + /* Manual handling of CAN Bus Error counters. See + * rkcanfd_get_corrected_berr_counter() for detailed + * explanation. + */ + if (priv->bec.txerr) + priv->bec.txerr--; + + *tx_done = true; + + stats->tx_packets++; + stats->tx_errors++; + + rkcanfd_xmit_retry(priv); + + return 0; +} + +static inline bool +rkcanfd_fifo_header_empty(const struct rkcanfd_fifo_header *header) +{ + /* Erratum 5: If the FIFO is empty, we read the same value for + * all elements. + */ + return header->frameinfo == header->id && + header->frameinfo == header->ts; +} + +static int rkcanfd_handle_rx_int_one(struct rkcanfd_priv *priv) +{ + struct net_device_stats *stats = &priv->ndev->stats; + struct canfd_frame cfd[1] = { }, *skb_cfd; + struct rkcanfd_fifo_header header[1] = { }; + struct sk_buff *skb; + unsigned int len; + int err; + + /* read header into separate struct and convert it later */ + rkcanfd_read_rep(priv, RKCANFD_REG_RX_FIFO_RDATA, + header, sizeof(*header)); + /* read data directly into cfd */ + rkcanfd_read_rep(priv, RKCANFD_REG_RX_FIFO_RDATA, + cfd->data, sizeof(cfd->data)); + + /* Erratum 5: Counters for TXEFIFO and RXFIFO may be wrong */ + if (rkcanfd_fifo_header_empty(header)) { + struct rkcanfd_stats *rkcanfd_stats = &priv->stats; + + u64_stats_update_begin(&rkcanfd_stats->syncp); + u64_stats_inc(&rkcanfd_stats->rx_fifo_empty_errors); + u64_stats_update_end(&rkcanfd_stats->syncp); + + return 0; + } + + len = rkcanfd_fifo_header_to_cfd_header(priv, header, cfd); + + /* Drop any received CAN-FD frames if CAN-FD mode is not + * requested. + */ + if (header->frameinfo & RKCANFD_REG_FD_FRAMEINFO_FDF && + !(priv->can.ctrlmode & CAN_CTRLMODE_FD)) { + stats->rx_dropped++; + + return 0; + } + + if (rkcanfd_get_tx_pending(priv)) { + bool tx_done = false; + + err = rkcanfd_rxstx_filter(priv, cfd, header->ts, &tx_done); + if (err) + return err; + if (tx_done && !(priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)) + return 0; + } + + /* Manual handling of CAN Bus Error counters. See + * rkcanfd_get_corrected_berr_counter() for detailed + * explanation. + */ + if (priv->bec.rxerr) + priv->bec.rxerr = min(CAN_ERROR_PASSIVE_THRESHOLD, + priv->bec.rxerr) - 1; + + if (header->frameinfo & RKCANFD_REG_FD_FRAMEINFO_FDF) + skb = alloc_canfd_skb(priv->ndev, &skb_cfd); + else + skb = alloc_can_skb(priv->ndev, (struct can_frame **)&skb_cfd); + + if (!skb) { + stats->rx_dropped++; + + return 0; + } + + memcpy(skb_cfd, cfd, len); + rkcanfd_skb_set_timestamp(priv, skb, header->ts); + + err = can_rx_offload_queue_timestamp(&priv->offload, skb, header->ts); + if (err) + stats->rx_fifo_errors++; + + return 0; +} + +static inline unsigned int +rkcanfd_rx_fifo_get_len(const struct rkcanfd_priv *priv) +{ + const u32 reg = rkcanfd_read(priv, RKCANFD_REG_RX_FIFO_CTRL); + + return FIELD_GET(RKCANFD_REG_RX_FIFO_CTRL_RX_FIFO_CNT, reg); +} + +int rkcanfd_handle_rx_int(struct rkcanfd_priv *priv) +{ + unsigned int len; + int err; + + while ((len = rkcanfd_rx_fifo_get_len(priv))) { + err = rkcanfd_handle_rx_int_one(priv); + if (err) + return err; + } + + return 0; +} |