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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c new file mode 100644 index 000000000..bf3f0f150 --- /dev/null +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c @@ -0,0 +1,512 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// mcp251xfd - Microchip MCP251xFD Family CAN controller driver +// +// Copyright (c) 2019, 2020, 2021 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// +// Based on: +// +// CAN bus driver for Microchip 25XXFD CAN Controller with SPI Interface +// +// Copyright (c) 2019 Martin Sperl <kernel@martin.sperl.org> +// + +#include <asm/unaligned.h> + +#include "mcp251xfd.h" +#include "mcp251xfd-ram.h" + +static inline u8 +mcp251xfd_cmd_prepare_write_reg(const struct mcp251xfd_priv *priv, + union mcp251xfd_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 = mcp251xfd_first_byte_set(mask); + last_byte = mcp251xfd_last_byte_set(mask); + len = last_byte - first_byte + 1; + + data = mcp251xfd_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 & MCP251XFD_QUIRK_CRC_REG) { + u16 crc; + + mcp251xfd_spi_cmd_crc_set_len_in_reg(&write_reg_buf->crc.cmd, + len); + /* CRC */ + len += sizeof(write_reg_buf->crc.cmd); + crc = mcp251xfd_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 void +mcp251xfd_ring_init_tef(struct mcp251xfd_priv *priv, u16 *base) +{ + struct mcp251xfd_tef_ring *tef_ring; + struct spi_transfer *xfer; + u32 val; + u16 addr; + u8 len; + int i; + + /* TEF */ + tef_ring = priv->tef; + tef_ring->head = 0; + tef_ring->tail = 0; + + /* TEF- and TX-FIFO have same number of objects */ + *base = mcp251xfd_get_tef_obj_addr(priv->tx->obj_num); + + /* FIFO IRQ enable */ + addr = MCP251XFD_REG_TEFCON; + val = MCP251XFD_REG_TEFCON_TEFOVIE | MCP251XFD_REG_TEFCON_TEFNEIE; + + len = mcp251xfd_cmd_prepare_write_reg(priv, &tef_ring->irq_enable_buf, + addr, val, val); + tef_ring->irq_enable_xfer.tx_buf = &tef_ring->irq_enable_buf; + tef_ring->irq_enable_xfer.len = len; + spi_message_init_with_transfers(&tef_ring->irq_enable_msg, + &tef_ring->irq_enable_xfer, 1); + + /* FIFO increment TEF tail pointer */ + addr = MCP251XFD_REG_TEFCON; + val = MCP251XFD_REG_TEFCON_UINC; + len = mcp251xfd_cmd_prepare_write_reg(priv, &tef_ring->uinc_buf, + addr, val, val); + + for (i = 0; i < ARRAY_SIZE(tef_ring->uinc_xfer); i++) { + xfer = &tef_ring->uinc_xfer[i]; + xfer->tx_buf = &tef_ring->uinc_buf; + xfer->len = len; + xfer->cs_change = 1; + xfer->cs_change_delay.value = 0; + xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; + } + + /* "cs_change == 1" on the last transfer results in an active + * chip select after the complete SPI message. This causes the + * controller to interpret the next register access as + * data. Set "cs_change" of the last transfer to "0" to + * properly deactivate the chip select at the end of the + * message. + */ + xfer->cs_change = 0; + + if (priv->tx_coalesce_usecs_irq || priv->tx_obj_num_coalesce_irq) { + val = MCP251XFD_REG_TEFCON_UINC | + MCP251XFD_REG_TEFCON_TEFOVIE | + MCP251XFD_REG_TEFCON_TEFHIE; + + len = mcp251xfd_cmd_prepare_write_reg(priv, + &tef_ring->uinc_irq_disable_buf, + addr, val, val); + xfer->tx_buf = &tef_ring->uinc_irq_disable_buf; + xfer->len = len; + } +} + +static void +mcp251xfd_tx_ring_init_tx_obj(const struct mcp251xfd_priv *priv, + const struct mcp251xfd_tx_ring *ring, + struct mcp251xfd_tx_obj *tx_obj, + const u8 rts_buf_len, + const u8 n) +{ + struct spi_transfer *xfer; + u16 addr; + + /* FIFO load */ + addr = mcp251xfd_get_tx_obj_addr(ring, n); + if (priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_TX) + mcp251xfd_spi_cmd_write_crc_set_addr(&tx_obj->buf.crc.cmd, + addr); + else + mcp251xfd_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 +mcp251xfd_ring_init_tx(struct mcp251xfd_priv *priv, u16 *base, u8 *fifo_nr) +{ + struct mcp251xfd_tx_ring *tx_ring; + struct mcp251xfd_tx_obj *tx_obj; + u32 val; + u16 addr; + u8 len; + int i; + + tx_ring = priv->tx; + tx_ring->head = 0; + tx_ring->tail = 0; + tx_ring->base = *base; + tx_ring->nr = 0; + tx_ring->fifo_nr = *fifo_nr; + + *base = mcp251xfd_get_tx_obj_addr(tx_ring, tx_ring->obj_num); + *fifo_nr += 1; + + /* FIFO request to send */ + addr = MCP251XFD_REG_FIFOCON(tx_ring->fifo_nr); + val = MCP251XFD_REG_FIFOCON_TXREQ | MCP251XFD_REG_FIFOCON_UINC; + len = mcp251xfd_cmd_prepare_write_reg(priv, &tx_ring->rts_buf, + addr, val, val); + + mcp251xfd_for_each_tx_obj(tx_ring, tx_obj, i) + mcp251xfd_tx_ring_init_tx_obj(priv, tx_ring, tx_obj, len, i); +} + +static void +mcp251xfd_ring_init_rx(struct mcp251xfd_priv *priv, u16 *base, u8 *fifo_nr) +{ + struct mcp251xfd_rx_ring *rx_ring; + struct spi_transfer *xfer; + u32 val; + u16 addr; + u8 len; + int i, j; + + mcp251xfd_for_each_rx_ring(priv, rx_ring, i) { + rx_ring->head = 0; + rx_ring->tail = 0; + rx_ring->base = *base; + rx_ring->nr = i; + rx_ring->fifo_nr = *fifo_nr; + + *base = mcp251xfd_get_rx_obj_addr(rx_ring, rx_ring->obj_num); + *fifo_nr += 1; + + /* FIFO IRQ enable */ + addr = MCP251XFD_REG_FIFOCON(rx_ring->fifo_nr); + val = MCP251XFD_REG_FIFOCON_RXOVIE | + MCP251XFD_REG_FIFOCON_TFNRFNIE; + len = mcp251xfd_cmd_prepare_write_reg(priv, &rx_ring->irq_enable_buf, + addr, val, val); + rx_ring->irq_enable_xfer.tx_buf = &rx_ring->irq_enable_buf; + rx_ring->irq_enable_xfer.len = len; + spi_message_init_with_transfers(&rx_ring->irq_enable_msg, + &rx_ring->irq_enable_xfer, 1); + + /* FIFO increment RX tail pointer */ + val = MCP251XFD_REG_FIFOCON_UINC; + len = mcp251xfd_cmd_prepare_write_reg(priv, &rx_ring->uinc_buf, + addr, val, val); + + for (j = 0; j < ARRAY_SIZE(rx_ring->uinc_xfer); j++) { + xfer = &rx_ring->uinc_xfer[j]; + xfer->tx_buf = &rx_ring->uinc_buf; + xfer->len = len; + xfer->cs_change = 1; + xfer->cs_change_delay.value = 0; + xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; + } + + /* "cs_change == 1" on the last transfer results in an + * active chip select after the complete SPI + * message. This causes the controller to interpret + * the next register access as data. Set "cs_change" + * of the last transfer to "0" to properly deactivate + * the chip select at the end of the message. + */ + xfer->cs_change = 0; + + /* Use 1st RX-FIFO for IRQ coalescing. If enabled + * (rx_coalesce_usecs_irq or rx_max_coalesce_frames_irq + * is activated), use the last transfer to disable: + * + * - TFNRFNIE (Receive FIFO Not Empty Interrupt) + * + * and enable: + * + * - TFHRFHIE (Receive FIFO Half Full Interrupt) + * - or - + * - TFERFFIE (Receive FIFO Full Interrupt) + * + * depending on rx_max_coalesce_frames_irq. + * + * The RXOVIE (Overflow Interrupt) is always enabled. + */ + if (rx_ring->nr == 0 && (priv->rx_coalesce_usecs_irq || + priv->rx_obj_num_coalesce_irq)) { + val = MCP251XFD_REG_FIFOCON_UINC | + MCP251XFD_REG_FIFOCON_RXOVIE; + + if (priv->rx_obj_num_coalesce_irq == rx_ring->obj_num) + val |= MCP251XFD_REG_FIFOCON_TFERFFIE; + else if (priv->rx_obj_num_coalesce_irq) + val |= MCP251XFD_REG_FIFOCON_TFHRFHIE; + + len = mcp251xfd_cmd_prepare_write_reg(priv, + &rx_ring->uinc_irq_disable_buf, + addr, val, val); + xfer->tx_buf = &rx_ring->uinc_irq_disable_buf; + xfer->len = len; + } + } +} + +int mcp251xfd_ring_init(struct mcp251xfd_priv *priv) +{ + const struct mcp251xfd_rx_ring *rx_ring; + u16 base = 0, ram_used; + u8 fifo_nr = 1; + int i; + + netdev_reset_queue(priv->ndev); + + mcp251xfd_ring_init_tef(priv, &base); + mcp251xfd_ring_init_rx(priv, &base, &fifo_nr); + mcp251xfd_ring_init_tx(priv, &base, &fifo_nr); + + /* mcp251xfd_handle_rxif() will iterate over all RX rings. + * Rings with their corresponding bit set in + * priv->regs_status.rxif are read out. + * + * If the chip is configured for only 1 RX-FIFO, and if there + * is an RX interrupt pending (RXIF in INT register is set), + * it must be the 1st RX-FIFO. + * + * We mark the RXIF of the 1st FIFO as pending here, so that + * we can skip the read of the RXIF register in + * mcp251xfd_read_regs_status() for the 1 RX-FIFO only case. + * + * If we use more than 1 RX-FIFO, this value gets overwritten + * in mcp251xfd_read_regs_status(), so set it unconditionally + * here. + */ + priv->regs_status.rxif = BIT(priv->rx[0]->fifo_nr); + + if (priv->tx_obj_num_coalesce_irq) { + netdev_dbg(priv->ndev, + "FIFO setup: TEF: 0x%03x: %2d*%zu bytes = %4zu bytes (coalesce)\n", + mcp251xfd_get_tef_obj_addr(0), + priv->tx_obj_num_coalesce_irq, + sizeof(struct mcp251xfd_hw_tef_obj), + priv->tx_obj_num_coalesce_irq * + sizeof(struct mcp251xfd_hw_tef_obj)); + + netdev_dbg(priv->ndev, + " 0x%03x: %2d*%zu bytes = %4zu bytes\n", + mcp251xfd_get_tef_obj_addr(priv->tx_obj_num_coalesce_irq), + priv->tx->obj_num - priv->tx_obj_num_coalesce_irq, + sizeof(struct mcp251xfd_hw_tef_obj), + (priv->tx->obj_num - priv->tx_obj_num_coalesce_irq) * + sizeof(struct mcp251xfd_hw_tef_obj)); + } else { + netdev_dbg(priv->ndev, + "FIFO setup: TEF: 0x%03x: %2d*%zu bytes = %4zu bytes\n", + mcp251xfd_get_tef_obj_addr(0), + priv->tx->obj_num, sizeof(struct mcp251xfd_hw_tef_obj), + priv->tx->obj_num * sizeof(struct mcp251xfd_hw_tef_obj)); + } + + mcp251xfd_for_each_rx_ring(priv, rx_ring, i) { + if (rx_ring->nr == 0 && priv->rx_obj_num_coalesce_irq) { + netdev_dbg(priv->ndev, + "FIFO setup: RX-%u: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes (coalesce)\n", + rx_ring->nr, rx_ring->fifo_nr, + mcp251xfd_get_rx_obj_addr(rx_ring, 0), + priv->rx_obj_num_coalesce_irq, rx_ring->obj_size, + priv->rx_obj_num_coalesce_irq * rx_ring->obj_size); + + if (priv->rx_obj_num_coalesce_irq == MCP251XFD_FIFO_DEPTH) + continue; + + netdev_dbg(priv->ndev, + " 0x%03x: %2u*%u bytes = %4u bytes\n", + mcp251xfd_get_rx_obj_addr(rx_ring, + priv->rx_obj_num_coalesce_irq), + rx_ring->obj_num - priv->rx_obj_num_coalesce_irq, + rx_ring->obj_size, + (rx_ring->obj_num - priv->rx_obj_num_coalesce_irq) * + rx_ring->obj_size); + } else { + netdev_dbg(priv->ndev, + "FIFO setup: RX-%u: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes\n", + rx_ring->nr, rx_ring->fifo_nr, + mcp251xfd_get_rx_obj_addr(rx_ring, 0), + rx_ring->obj_num, rx_ring->obj_size, + rx_ring->obj_num * rx_ring->obj_size); + } + } + + netdev_dbg(priv->ndev, + "FIFO setup: TX: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes\n", + priv->tx->fifo_nr, + mcp251xfd_get_tx_obj_addr(priv->tx, 0), + priv->tx->obj_num, priv->tx->obj_size, + priv->tx->obj_num * priv->tx->obj_size); + + netdev_dbg(priv->ndev, + "FIFO setup: free: %4d bytes\n", + MCP251XFD_RAM_SIZE - (base - MCP251XFD_RAM_START)); + + ram_used = base - MCP251XFD_RAM_START; + if (ram_used > MCP251XFD_RAM_SIZE) { + netdev_err(priv->ndev, + "Error during ring configuration, using more RAM (%u bytes) than available (%u bytes).\n", + ram_used, MCP251XFD_RAM_SIZE); + return -ENOMEM; + } + + return 0; +} + +void mcp251xfd_ring_free(struct mcp251xfd_priv *priv) +{ + int i; + + for (i = ARRAY_SIZE(priv->rx) - 1; i >= 0; i--) { + kfree(priv->rx[i]); + priv->rx[i] = NULL; + } +} + +static enum hrtimer_restart mcp251xfd_rx_irq_timer(struct hrtimer *t) +{ + struct mcp251xfd_priv *priv = container_of(t, struct mcp251xfd_priv, + rx_irq_timer); + struct mcp251xfd_rx_ring *ring = priv->rx[0]; + + if (test_bit(MCP251XFD_FLAGS_DOWN, priv->flags)) + return HRTIMER_NORESTART; + + spi_async(priv->spi, &ring->irq_enable_msg); + + return HRTIMER_NORESTART; +} + +static enum hrtimer_restart mcp251xfd_tx_irq_timer(struct hrtimer *t) +{ + struct mcp251xfd_priv *priv = container_of(t, struct mcp251xfd_priv, + tx_irq_timer); + struct mcp251xfd_tef_ring *ring = priv->tef; + + if (test_bit(MCP251XFD_FLAGS_DOWN, priv->flags)) + return HRTIMER_NORESTART; + + spi_async(priv->spi, &ring->irq_enable_msg); + + return HRTIMER_NORESTART; +} + +const struct can_ram_config mcp251xfd_ram_config = { + .rx = { + .size[CAN_RAM_MODE_CAN] = sizeof(struct mcp251xfd_hw_rx_obj_can), + .size[CAN_RAM_MODE_CANFD] = sizeof(struct mcp251xfd_hw_rx_obj_canfd), + .min = MCP251XFD_RX_OBJ_NUM_MIN, + .max = MCP251XFD_RX_OBJ_NUM_MAX, + .def[CAN_RAM_MODE_CAN] = CAN_RAM_NUM_MAX, + .def[CAN_RAM_MODE_CANFD] = CAN_RAM_NUM_MAX, + .fifo_num = MCP251XFD_FIFO_RX_NUM, + .fifo_depth_min = MCP251XFD_RX_FIFO_DEPTH_MIN, + .fifo_depth_coalesce_min = MCP251XFD_RX_FIFO_DEPTH_COALESCE_MIN, + }, + .tx = { + .size[CAN_RAM_MODE_CAN] = sizeof(struct mcp251xfd_hw_tef_obj) + + sizeof(struct mcp251xfd_hw_tx_obj_can), + .size[CAN_RAM_MODE_CANFD] = sizeof(struct mcp251xfd_hw_tef_obj) + + sizeof(struct mcp251xfd_hw_tx_obj_canfd), + .min = MCP251XFD_TX_OBJ_NUM_MIN, + .max = MCP251XFD_TX_OBJ_NUM_MAX, + .def[CAN_RAM_MODE_CAN] = MCP251XFD_TX_OBJ_NUM_CAN_DEFAULT, + .def[CAN_RAM_MODE_CANFD] = MCP251XFD_TX_OBJ_NUM_CANFD_DEFAULT, + .fifo_num = MCP251XFD_FIFO_TX_NUM, + .fifo_depth_min = MCP251XFD_TX_FIFO_DEPTH_MIN, + .fifo_depth_coalesce_min = MCP251XFD_TX_FIFO_DEPTH_COALESCE_MIN, + }, + .size = MCP251XFD_RAM_SIZE, + .fifo_depth = MCP251XFD_FIFO_DEPTH, +}; + +int mcp251xfd_ring_alloc(struct mcp251xfd_priv *priv) +{ + const bool fd_mode = mcp251xfd_is_fd_mode(priv); + struct mcp251xfd_tx_ring *tx_ring = priv->tx; + struct mcp251xfd_rx_ring *rx_ring; + u8 tx_obj_size, rx_obj_size; + u8 rem, i; + + /* switching from CAN-2.0 to CAN-FD mode or vice versa */ + if (fd_mode != test_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags)) { + struct can_ram_layout layout; + + can_ram_get_layout(&layout, &mcp251xfd_ram_config, NULL, NULL, fd_mode); + priv->rx_obj_num = layout.default_rx; + tx_ring->obj_num = layout.default_tx; + } + + if (fd_mode) { + tx_obj_size = sizeof(struct mcp251xfd_hw_tx_obj_canfd); + rx_obj_size = sizeof(struct mcp251xfd_hw_rx_obj_canfd); + set_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags); + } else { + tx_obj_size = sizeof(struct mcp251xfd_hw_tx_obj_can); + rx_obj_size = sizeof(struct mcp251xfd_hw_rx_obj_can); + clear_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags); + } + + tx_ring->obj_size = tx_obj_size; + + rem = priv->rx_obj_num; + for (i = 0; i < ARRAY_SIZE(priv->rx) && rem; i++) { + u8 rx_obj_num; + + if (i == 0 && priv->rx_obj_num_coalesce_irq) + rx_obj_num = min_t(u8, priv->rx_obj_num_coalesce_irq * 2, + MCP251XFD_FIFO_DEPTH); + else + rx_obj_num = min_t(u8, rounddown_pow_of_two(rem), + MCP251XFD_FIFO_DEPTH); + rem -= rx_obj_num; + + rx_ring = kzalloc(sizeof(*rx_ring) + rx_obj_size * rx_obj_num, + GFP_KERNEL); + if (!rx_ring) { + mcp251xfd_ring_free(priv); + return -ENOMEM; + } + + rx_ring->obj_num = rx_obj_num; + rx_ring->obj_size = rx_obj_size; + priv->rx[i] = rx_ring; + } + priv->rx_ring_num = i; + + hrtimer_init(&priv->rx_irq_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + priv->rx_irq_timer.function = mcp251xfd_rx_irq_timer; + + hrtimer_init(&priv->tx_irq_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + priv->tx_irq_timer.function = mcp251xfd_tx_irq_timer; + + return 0; +} |