diff --git a/drivers/net/ethernet/oa_tc6.c b/drivers/net/ethernet/oa_tc6.c index 8958af863b6e..bbc4b7fce64c 100644 --- a/drivers/net/ethernet/oa_tc6.c +++ b/drivers/net/ethernet/oa_tc6.c @@ -27,6 +27,13 @@ /* Status Register #0 */ #define OA_TC6_REG_STATUS0 0x0008 #define STATUS0_RESETC BIT(6) /* Reset Complete */ +#define STATUS0_HEADER_ERROR BIT(5) +#define STATUS0_LOSS_OF_FRAME_ERROR BIT(4) +#define STATUS0_TX_PROTOCOL_ERROR BIT(0) + +/* Buffer Status Register */ +#define OA_TC6_REG_BUFFER_STATUS 0x000B +#define BUFFER_STATUS_TX_CREDITS_AVAILABLE GENMASK(15, 8) /* Interrupt Mask Register #0 */ #define OA_TC6_REG_INT_MASK0 0x000C @@ -47,6 +54,21 @@ #define OA_TC6_CTRL_HEADER_LENGTH GENMASK(7, 1) #define OA_TC6_CTRL_HEADER_PARITY BIT(0) +/* Data header */ +#define OA_TC6_DATA_HEADER_DATA_NOT_CTRL BIT(31) +#define OA_TC6_DATA_HEADER_DATA_VALID BIT(21) +#define OA_TC6_DATA_HEADER_START_VALID BIT(20) +#define OA_TC6_DATA_HEADER_START_WORD_OFFSET GENMASK(19, 16) +#define OA_TC6_DATA_HEADER_END_VALID BIT(14) +#define OA_TC6_DATA_HEADER_END_BYTE_OFFSET GENMASK(13, 8) +#define OA_TC6_DATA_HEADER_PARITY BIT(0) + +/* Data footer */ +#define OA_TC6_DATA_FOOTER_EXTENDED_STS BIT(31) +#define OA_TC6_DATA_FOOTER_RXD_HEADER_BAD BIT(30) +#define OA_TC6_DATA_FOOTER_CONFIG_SYNC BIT(29) +#define OA_TC6_DATA_FOOTER_TX_CREDITS GENMASK(5, 1) + /* PHY – Clause 45 registers memory map selector (MMS) as per table 6 in the * OPEN Alliance specification. */ @@ -64,6 +86,13 @@ (OA_TC6_CTRL_MAX_REGISTERS *\ OA_TC6_CTRL_REG_VALUE_SIZE) +\ OA_TC6_CTRL_IGNORED_SIZE) +#define OA_TC6_CHUNK_PAYLOAD_SIZE 64 +#define OA_TC6_DATA_HEADER_SIZE 4 +#define OA_TC6_CHUNK_SIZE (OA_TC6_DATA_HEADER_SIZE +\ + OA_TC6_CHUNK_PAYLOAD_SIZE) +#define OA_TC6_MAX_TX_CHUNKS 48 +#define OA_TC6_SPI_DATA_BUF_SIZE (OA_TC6_MAX_TX_CHUNKS *\ + OA_TC6_CHUNK_SIZE) #define STATUS0_RESETC_POLL_DELAY 1000 #define STATUS0_RESETC_POLL_TIMEOUT 1000000 @@ -77,10 +106,20 @@ struct oa_tc6 { struct mutex spi_ctrl_lock; /* Protects spi control transfer */ void *spi_ctrl_tx_buf; void *spi_ctrl_rx_buf; + void *spi_data_tx_buf; + void *spi_data_rx_buf; + struct sk_buff *ongoing_tx_skb; + struct sk_buff *waiting_tx_skb; + struct task_struct *spi_thread; + wait_queue_head_t spi_wq; + u16 tx_skb_offset; + u16 spi_data_tx_buf_offset; + u16 tx_credits; }; enum oa_tc6_header_type { OA_TC6_CTRL_HEADER, + OA_TC6_DATA_HEADER, }; enum oa_tc6_register_op { @@ -88,14 +127,34 @@ enum oa_tc6_register_op { OA_TC6_CTRL_REG_WRITE = 1, }; +enum oa_tc6_data_valid_info { + OA_TC6_DATA_INVALID, + OA_TC6_DATA_VALID, +}; + +enum oa_tc6_data_start_valid_info { + OA_TC6_DATA_START_INVALID, + OA_TC6_DATA_START_VALID, +}; + +enum oa_tc6_data_end_valid_info { + OA_TC6_DATA_END_INVALID, + OA_TC6_DATA_END_VALID, +}; + static int oa_tc6_spi_transfer(struct oa_tc6 *tc6, enum oa_tc6_header_type header_type, u16 length) { struct spi_transfer xfer = { 0 }; struct spi_message msg; - xfer.tx_buf = tc6->spi_ctrl_tx_buf; - xfer.rx_buf = tc6->spi_ctrl_rx_buf; + if (header_type == OA_TC6_DATA_HEADER) { + xfer.tx_buf = tc6->spi_data_tx_buf; + xfer.rx_buf = tc6->spi_data_rx_buf; + } else { + xfer.tx_buf = tc6->spi_ctrl_tx_buf; + xfer.rx_buf = tc6->spi_ctrl_rx_buf; + } xfer.len = length; spi_message_init(&msg); @@ -578,6 +637,309 @@ static int oa_tc6_enable_data_transfer(struct oa_tc6 *tc6) return oa_tc6_write_register(tc6, OA_TC6_REG_CONFIG0, value); } +static void oa_tc6_cleanup_ongoing_tx_skb(struct oa_tc6 *tc6) +{ + if (tc6->ongoing_tx_skb) { + tc6->netdev->stats.tx_dropped++; + kfree_skb(tc6->ongoing_tx_skb); + tc6->ongoing_tx_skb = NULL; + } +} + +static int oa_tc6_process_extended_status(struct oa_tc6 *tc6) +{ + u32 value; + int ret; + + ret = oa_tc6_read_register(tc6, OA_TC6_REG_STATUS0, &value); + if (ret) { + netdev_err(tc6->netdev, "STATUS0 register read failed: %d\n", + ret); + return ret; + } + + /* Clear the error interrupts status */ + ret = oa_tc6_write_register(tc6, OA_TC6_REG_STATUS0, value); + if (ret) { + netdev_err(tc6->netdev, "STATUS0 register write failed: %d\n", + ret); + return ret; + } + + if (FIELD_GET(STATUS0_TX_PROTOCOL_ERROR, value)) { + netdev_err(tc6->netdev, "Transmit protocol error\n"); + return -ENODEV; + } + /* TODO: Currently loss of frame and header errors are treated as + * non-recoverable errors. They will be handled in the next version. + */ + if (FIELD_GET(STATUS0_LOSS_OF_FRAME_ERROR, value)) { + netdev_err(tc6->netdev, "Loss of frame error\n"); + return -ENODEV; + } + if (FIELD_GET(STATUS0_HEADER_ERROR, value)) { + netdev_err(tc6->netdev, "Header error\n"); + return -ENODEV; + } + + return 0; +} + +static int oa_tc6_process_rx_chunk_footer(struct oa_tc6 *tc6, u32 footer) +{ + /* Process rx chunk footer for the following, + * 1. tx credits + * 2. errors if any from MAC-PHY + */ + tc6->tx_credits = FIELD_GET(OA_TC6_DATA_FOOTER_TX_CREDITS, footer); + + if (FIELD_GET(OA_TC6_DATA_FOOTER_EXTENDED_STS, footer)) { + int ret = oa_tc6_process_extended_status(tc6); + + if (ret) + return ret; + } + + /* TODO: Currently received header bad and configuration unsync errors + * are treated as non-recoverable errors. They will be handled in the + * next version. + */ + if (FIELD_GET(OA_TC6_DATA_FOOTER_RXD_HEADER_BAD, footer)) { + netdev_err(tc6->netdev, "Rxd header bad error\n"); + return -ENODEV; + } + + if (!FIELD_GET(OA_TC6_DATA_FOOTER_CONFIG_SYNC, footer)) { + netdev_err(tc6->netdev, "Config unsync error\n"); + return -ENODEV; + } + + return 0; +} + +static u32 oa_tc6_get_rx_chunk_footer(struct oa_tc6 *tc6, u16 footer_offset) +{ + u8 *rx_buf = tc6->spi_data_rx_buf; + __be32 footer; + + footer = *((__be32 *)&rx_buf[footer_offset]); + + return be32_to_cpu(footer); +} + +static int oa_tc6_process_spi_data_rx_buf(struct oa_tc6 *tc6, u16 length) +{ + u16 no_of_rx_chunks = length / OA_TC6_CHUNK_SIZE; + u32 footer; + int ret; + + /* All the rx chunks in the receive SPI data buffer are examined here */ + for (int i = 0; i < no_of_rx_chunks; i++) { + /* Last 4 bytes in each received chunk consist footer info */ + footer = oa_tc6_get_rx_chunk_footer(tc6, i * OA_TC6_CHUNK_SIZE + + OA_TC6_CHUNK_PAYLOAD_SIZE); + + ret = oa_tc6_process_rx_chunk_footer(tc6, footer); + if (ret) + return ret; + } + + return 0; +} + +static __be32 oa_tc6_prepare_data_header(bool data_valid, bool start_valid, + bool end_valid, u8 end_byte_offset) +{ + u32 header = FIELD_PREP(OA_TC6_DATA_HEADER_DATA_NOT_CTRL, + OA_TC6_DATA_HEADER) | + FIELD_PREP(OA_TC6_DATA_HEADER_DATA_VALID, data_valid) | + FIELD_PREP(OA_TC6_DATA_HEADER_START_VALID, start_valid) | + FIELD_PREP(OA_TC6_DATA_HEADER_END_VALID, end_valid) | + FIELD_PREP(OA_TC6_DATA_HEADER_END_BYTE_OFFSET, + end_byte_offset); + + header |= FIELD_PREP(OA_TC6_DATA_HEADER_PARITY, + oa_tc6_get_parity(header)); + + return cpu_to_be32(header); +} + +static void oa_tc6_add_tx_skb_to_spi_buf(struct oa_tc6 *tc6) +{ + enum oa_tc6_data_end_valid_info end_valid = OA_TC6_DATA_END_INVALID; + __be32 *tx_buf = tc6->spi_data_tx_buf + tc6->spi_data_tx_buf_offset; + u16 remaining_len = tc6->ongoing_tx_skb->len - tc6->tx_skb_offset; + u8 *tx_skb_data = tc6->ongoing_tx_skb->data + tc6->tx_skb_offset; + enum oa_tc6_data_start_valid_info start_valid; + u8 end_byte_offset = 0; + u16 length_to_copy; + + /* Initial value is assigned here to avoid more than 80 characters in + * the declaration place. + */ + start_valid = OA_TC6_DATA_START_INVALID; + + /* Set start valid if the current tx chunk contains the start of the tx + * ethernet frame. + */ + if (!tc6->tx_skb_offset) + start_valid = OA_TC6_DATA_START_VALID; + + /* If the remaining tx skb length is more than the chunk payload size of + * 64 bytes then copy only 64 bytes and leave the ongoing tx skb for + * next tx chunk. + */ + length_to_copy = min_t(u16, remaining_len, OA_TC6_CHUNK_PAYLOAD_SIZE); + + /* Copy the tx skb data to the tx chunk payload buffer */ + memcpy(tx_buf + 1, tx_skb_data, length_to_copy); + tc6->tx_skb_offset += length_to_copy; + + /* Set end valid if the current tx chunk contains the end of the tx + * ethernet frame. + */ + if (tc6->ongoing_tx_skb->len == tc6->tx_skb_offset) { + end_valid = OA_TC6_DATA_END_VALID; + end_byte_offset = length_to_copy - 1; + tc6->tx_skb_offset = 0; + tc6->netdev->stats.tx_bytes += tc6->ongoing_tx_skb->len; + tc6->netdev->stats.tx_packets++; + kfree_skb(tc6->ongoing_tx_skb); + tc6->ongoing_tx_skb = NULL; + } + + *tx_buf = oa_tc6_prepare_data_header(OA_TC6_DATA_VALID, start_valid, + end_valid, end_byte_offset); + tc6->spi_data_tx_buf_offset += OA_TC6_CHUNK_SIZE; +} + +static u16 oa_tc6_prepare_spi_tx_buf_for_tx_skbs(struct oa_tc6 *tc6) +{ + u16 used_tx_credits; + + /* Get tx skbs and convert them into tx chunks based on the tx credits + * available. + */ + for (used_tx_credits = 0; used_tx_credits < tc6->tx_credits; + used_tx_credits++) { + if (!tc6->ongoing_tx_skb) { + tc6->ongoing_tx_skb = tc6->waiting_tx_skb; + tc6->waiting_tx_skb = NULL; + } + if (!tc6->ongoing_tx_skb) + break; + oa_tc6_add_tx_skb_to_spi_buf(tc6); + } + + return used_tx_credits * OA_TC6_CHUNK_SIZE; +} + +static int oa_tc6_try_spi_transfer(struct oa_tc6 *tc6) +{ + int ret; + + while (true) { + u16 spi_length = 0; + + tc6->spi_data_tx_buf_offset = 0; + + if (tc6->ongoing_tx_skb || tc6->waiting_tx_skb) + spi_length = oa_tc6_prepare_spi_tx_buf_for_tx_skbs(tc6); + + if (spi_length == 0) + break; + + ret = oa_tc6_spi_transfer(tc6, OA_TC6_DATA_HEADER, spi_length); + if (ret) { + netdev_err(tc6->netdev, "SPI data transfer failed: %d\n", + ret); + return ret; + } + + ret = oa_tc6_process_spi_data_rx_buf(tc6, spi_length); + if (ret) { + oa_tc6_cleanup_ongoing_tx_skb(tc6); + netdev_err(tc6->netdev, "Device error: %d\n", ret); + return ret; + } + + if (!tc6->waiting_tx_skb && netif_queue_stopped(tc6->netdev)) + netif_wake_queue(tc6->netdev); + } + + return 0; +} + +static int oa_tc6_spi_thread_handler(void *data) +{ + struct oa_tc6 *tc6 = data; + int ret; + + while (likely(!kthread_should_stop())) { + /* This kthread will be waken up if there is a tx skb */ + wait_event_interruptible(tc6->spi_wq, tc6->waiting_tx_skb || + kthread_should_stop()); + + if (kthread_should_stop()) + break; + + ret = oa_tc6_try_spi_transfer(tc6); + if (ret) + return ret; + } + + return 0; +} + +static int oa_tc6_update_buffer_status_from_register(struct oa_tc6 *tc6) +{ + u32 value; + int ret; + + /* Initially tx credits to be updated from the register as there is no + * data transfer performed yet. Later it will be updated from the rx + * footer. + */ + ret = oa_tc6_read_register(tc6, OA_TC6_REG_BUFFER_STATUS, &value); + if (ret) + return ret; + + tc6->tx_credits = FIELD_GET(BUFFER_STATUS_TX_CREDITS_AVAILABLE, value); + + return 0; +} + +/** + * oa_tc6_start_xmit - function for sending the tx skb which consists ethernet + * frame. + * @tc6: oa_tc6 struct. + * @skb: socket buffer in which the ethernet frame is stored. + * + * Return: NETDEV_TX_OK if the transmit ethernet frame skb added in the tx_skb_q + * otherwise returns NETDEV_TX_BUSY. + */ +netdev_tx_t oa_tc6_start_xmit(struct oa_tc6 *tc6, struct sk_buff *skb) +{ + if (tc6->waiting_tx_skb) { + netif_stop_queue(tc6->netdev); + return NETDEV_TX_BUSY; + } + + if (skb_linearize(skb)) { + dev_kfree_skb_any(skb); + tc6->netdev->stats.tx_dropped++; + return NETDEV_TX_OK; + } + + tc6->waiting_tx_skb = skb; + + /* Wake spi kthread to perform spi transfer */ + wake_up_interruptible(&tc6->spi_wq); + + return NETDEV_TX_OK; +} +EXPORT_SYMBOL_GPL(oa_tc6_start_xmit); + /** * oa_tc6_init - allocates and initializes oa_tc6 structure. * @spi: device with which data will be exchanged. @@ -616,6 +978,18 @@ struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev) if (!tc6->spi_ctrl_rx_buf) return NULL; + tc6->spi_data_tx_buf = devm_kzalloc(&tc6->spi->dev, + OA_TC6_SPI_DATA_BUF_SIZE, + GFP_KERNEL); + if (!tc6->spi_data_tx_buf) + return NULL; + + tc6->spi_data_rx_buf = devm_kzalloc(&tc6->spi->dev, + OA_TC6_SPI_DATA_BUF_SIZE, + GFP_KERNEL); + if (!tc6->spi_data_rx_buf) + return NULL; + ret = oa_tc6_sw_reset_macphy(tc6); if (ret) { dev_err(&tc6->spi->dev, @@ -644,6 +1018,24 @@ struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev) goto phy_exit; } + ret = oa_tc6_update_buffer_status_from_register(tc6); + if (ret) { + dev_err(&tc6->spi->dev, + "Failed to update buffer status: %d\n", ret); + goto phy_exit; + } + + init_waitqueue_head(&tc6->spi_wq); + + tc6->spi_thread = kthread_run(oa_tc6_spi_thread_handler, tc6, + "oa-tc6-spi-thread"); + if (IS_ERR(tc6->spi_thread)) { + dev_err(&tc6->spi->dev, "Failed to create SPI thread\n"); + goto phy_exit; + } + + sched_set_fifo(tc6->spi_thread); + return tc6; phy_exit: @@ -659,6 +1051,9 @@ EXPORT_SYMBOL_GPL(oa_tc6_init); void oa_tc6_exit(struct oa_tc6 *tc6) { oa_tc6_phy_exit(tc6); + kthread_stop(tc6->spi_thread); + dev_kfree_skb_any(tc6->ongoing_tx_skb); + dev_kfree_skb_any(tc6->waiting_tx_skb); } EXPORT_SYMBOL_GPL(oa_tc6_exit); diff --git a/include/linux/oa_tc6.h b/include/linux/oa_tc6.h index 606ba9f1e663..5c7811ac9cbe 100644 --- a/include/linux/oa_tc6.h +++ b/include/linux/oa_tc6.h @@ -20,3 +20,4 @@ int oa_tc6_write_registers(struct oa_tc6 *tc6, u32 address, u32 value[], int oa_tc6_read_register(struct oa_tc6 *tc6, u32 address, u32 *value); int oa_tc6_read_registers(struct oa_tc6 *tc6, u32 address, u32 value[], u8 length); +netdev_tx_t oa_tc6_start_xmit(struct oa_tc6 *tc6, struct sk_buff *skb);