diff options
| -rw-r--r-- | drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c | 2 | ||||
| -rw-r--r-- | drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c | 54 | ||||
| -rw-r--r-- | drivers/net/can/spi/mcp251xfd/mcp251xfd.h | 13 |
3 files changed, 43 insertions, 26 deletions
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c index 8464fc4f37d0..7bd2bcb5cf87 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c @@ -486,6 +486,8 @@ int mcp251xfd_ring_alloc(struct mcp251xfd_priv *priv) clear_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags); } + tx_ring->obj_num_shift_to_u8 = BITS_PER_TYPE(tx_ring->obj_num) - + ilog2(tx_ring->obj_num); tx_ring->obj_size = tx_obj_size; rem = priv->rx_obj_num; diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c index 4bc8d71fc491..3d9c348ad868 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c @@ -2,7 +2,7 @@ // // mcp251xfd - Microchip MCP251xFD Family CAN controller driver // -// Copyright (c) 2019, 2020, 2021 Pengutronix, +// Copyright (c) 2019, 2020, 2021, 2023 Pengutronix, // Marc Kleine-Budde <kernel@pengutronix.de> // // Based on: @@ -16,6 +16,11 @@ #include "mcp251xfd.h" +static inline bool mcp251xfd_tx_fifo_sta_full(u32 fifo_sta) +{ + return !(fifo_sta & MCP251XFD_REG_FIFOSTA_TFNRFNIF); +} + static inline int mcp251xfd_tef_tail_get_from_chip(const struct mcp251xfd_priv *priv, u8 *tef_tail) @@ -120,28 +125,44 @@ mcp251xfd_handle_tefif_one(struct mcp251xfd_priv *priv, return 0; } -static int mcp251xfd_tef_ring_update(struct mcp251xfd_priv *priv) +static int +mcp251xfd_get_tef_len(struct mcp251xfd_priv *priv, u8 *len_p) { const struct mcp251xfd_tx_ring *tx_ring = priv->tx; - unsigned int new_head; - u8 chip_tx_tail; + const u8 shift = tx_ring->obj_num_shift_to_u8; + u8 chip_tx_tail, tail, len; + u32 fifo_sta; int err; - err = mcp251xfd_tx_tail_get_from_chip(priv, &chip_tx_tail); + err = regmap_read(priv->map_reg, MCP251XFD_REG_FIFOSTA(priv->tx->fifo_nr), + &fifo_sta); 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, ... + if (mcp251xfd_tx_fifo_sta_full(fifo_sta)) { + *len_p = tx_ring->obj_num; + return 0; + } + + chip_tx_tail = FIELD_GET(MCP251XFD_REG_FIFOSTA_FIFOCI_MASK, fifo_sta); + + err = mcp251xfd_check_tef_tail(priv); + if (err) + return err; + tail = mcp251xfd_get_tef_tail(priv); + + /* First shift to full u8. The subtraction works on signed + * values, that keeps the difference steady around the u8 + * overflow. The right shift acts on len, which is an u8. */ - 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; + BUILD_BUG_ON(sizeof(tx_ring->obj_num) != sizeof(chip_tx_tail)); + BUILD_BUG_ON(sizeof(tx_ring->obj_num) != sizeof(tail)); + BUILD_BUG_ON(sizeof(tx_ring->obj_num) != sizeof(len)); - /* ... but it cannot exceed the TX head. */ - priv->tef->head = min(new_head, tx_ring->head); + len = (chip_tx_tail << shift) - (tail << shift); + *len_p = len >> shift; - return mcp251xfd_check_tef_tail(priv); + return 0; } static inline int @@ -182,13 +203,12 @@ int mcp251xfd_handle_tefif(struct mcp251xfd_priv *priv) u8 tef_tail, len, l; int err, i; - err = mcp251xfd_tef_ring_update(priv); + err = mcp251xfd_get_tef_len(priv, &len); if (err) return err; tef_tail = mcp251xfd_get_tef_tail(priv); - len = mcp251xfd_get_tef_len(priv); - l = mcp251xfd_get_tef_linear_len(priv); + l = mcp251xfd_get_tef_linear_len(priv, len); err = mcp251xfd_tef_obj_read(priv, hw_tef_obj, tef_tail, l); if (err) return err; @@ -223,6 +243,8 @@ out_netif_wake_queue: struct mcp251xfd_tx_ring *tx_ring = priv->tx; int offset; + ring->head += len; + /* Increment the TEF FIFO tail pointer 'len' times in * a single SPI message. * diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd.h b/drivers/net/can/spi/mcp251xfd/mcp251xfd.h index d32ece3d7aee..dcbbd2b2fae8 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd.h +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd.h @@ -524,6 +524,7 @@ struct mcp251xfd_tef_ring { /* u8 obj_num equals tx_ring->obj_num */ /* u8 obj_size equals sizeof(struct mcp251xfd_hw_tef_obj) */ + /* u8 obj_num_shift_to_u8 equals tx_ring->obj_num_shift_to_u8 */ union mcp251xfd_write_reg_buf irq_enable_buf; struct spi_transfer irq_enable_xfer; @@ -542,6 +543,7 @@ struct mcp251xfd_tx_ring { u8 nr; u8 fifo_nr; u8 obj_num; + u8 obj_num_shift_to_u8; u8 obj_size; struct mcp251xfd_tx_obj obj[MCP251XFD_TX_OBJ_NUM_MAX]; @@ -882,17 +884,8 @@ static inline u8 mcp251xfd_get_tef_tail(const struct mcp251xfd_priv *priv) return priv->tef->tail & (priv->tx->obj_num - 1); } -static inline u8 mcp251xfd_get_tef_len(const struct mcp251xfd_priv *priv) -{ - return priv->tef->head - priv->tef->tail; -} - -static inline u8 mcp251xfd_get_tef_linear_len(const struct mcp251xfd_priv *priv) +static inline u8 mcp251xfd_get_tef_linear_len(const struct mcp251xfd_priv *priv, u8 len) { - u8 len; - - len = mcp251xfd_get_tef_len(priv); - return min_t(u8, len, priv->tx->obj_num - mcp251xfd_get_tef_tail(priv)); } |