Re: [RFC PATCH net-next 4/6] net: ethernet: implement data transaction interface

From: Ziyang Xuan (William)
Date: Mon Sep 11 2023 - 17:06:07 EST

> The ethernet frame to be sent to MAC-PHY is converted into multiple
> transmit data chunks. A transmit data chunk consists of a 4-byte data
> header followed by the transmit data chunk payload.
>
> The received ethernet frame from the network is converted into multiple
> receive data chunks by the MAC-PHY and a receive data chunk consists of
> the receive data chunk payload followed by a 4-byte data footer at the
> end.
>
> The MAC-PHY shall support a default data chunk payload size of 64 bytes.
> Data chunk payload sizes of 32, 16, or 8 bytes may also be supported. The
> data chunk payload is always a multiple of 4 bytes.
>
> The 4-byte data header occurs at the beginning of each transmit data
> chunk on MOSI and the 4-byte data footer occurs at the end of each
> receive data chunk on MISO. The data header and footer contain the
> information needed to determine the validity and location of the transmit
> and receive frame data within the data chunk payload. Ethernet frames
> shall be aligned to a 32-bit boundary within the data chunk payload.
>
> Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@xxxxxxxxxxxxx>
> ---
> drivers/net/ethernet/oa_tc6.c | 425 +++++++++++++++++++++++++++++++++-
> include/linux/oa_tc6.h | 65 +++++-
> 2 files changed, 485 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/ethernet/oa_tc6.c b/drivers/net/ethernet/oa_tc6.c
> index 65a7317f768d..20138b178185 100644
> --- a/drivers/net/ethernet/oa_tc6.c
> +++ b/drivers/net/ethernet/oa_tc6.c
> @@ -5,6 +5,7 @@
> * Author: Parthiban Veerasooran <parthiban.veerasooran@xxxxxxxxxxxxx>
> */
>
> +#include <linux/etherdevice.h>
> #include <linux/bitfield.h>
> #include <linux/interrupt.h>
> #include <linux/oa_tc6.h>
> @@ -193,17 +194,224 @@ int oa_tc6_perform_ctrl(struct oa_tc6 *tc6, u32 addr, u32 val[], u8 len,
> return ret;
> }
>
> +static u16 oa_tc6_prepare_empty_chunk(struct oa_tc6 *tc6, u8 *buf, u8 cp_count)
> +{
> + u32 hdr;
> +
> + /* Prepare empty chunks used for getting interrupt information or if
> + * receive data available.
> + */
> + for (u8 i = 0; i < cp_count; i++) {
> + hdr = FIELD_PREP(DATA_HDR_DNC, 1);
> + hdr |= FIELD_PREP(DATA_HDR_P, oa_tc6_get_parity(hdr));
> + hdr = cpu_to_be32(hdr);
> + *(u32 *)&buf[i * (tc6->cps + TC6_HDR_SIZE)] = hdr;
> + memset(&buf[TC6_HDR_SIZE + (i * (tc6->cps + TC6_HDR_SIZE))], 0,
> + tc6->cps);
> + }
> +
> + return cp_count * (tc6->cps + TC6_HDR_SIZE);
> +}
> +
> +static void oa_tc6_rx_eth_ready(struct oa_tc6 *tc6)
> +{
> + struct sk_buff *skb = NULL;
Unnecessary initialization for skb.

> +
> + /* Send the received ethernet packet to network layer */
> + skb = netdev_alloc_skb(tc6->netdev, tc6->rxd_bytes + NET_IP_ALIGN);
> + if (!skb) {
> + tc6->netdev->stats.rx_dropped++;
> + netdev_err(tc6->netdev, "Out of memory for rx'd frame");
> + } else {
> + skb_reserve(skb, NET_IP_ALIGN);
> + memcpy(skb_put(skb, tc6->rxd_bytes), &tc6->eth_rx_buf[0],
> + tc6->rxd_bytes);
> + skb->protocol = eth_type_trans(skb, tc6->netdev);
> + tc6->netdev->stats.rx_packets++;
> + tc6->netdev->stats.rx_bytes += tc6->rxd_bytes;
> + netif_rx(skb);
netif_rx() may fail, I think it is good to add check and statistics.

> + }
> +}
> +
> +static int oa_tc6_process_exst(struct oa_tc6 *tc6)
> +{
> + u32 regval;
> + int ret;
> +
> + ret = oa_tc6_read_register(tc6, OA_TC6_STS0, &regval, 1);
> + if (ret) {
> + netdev_err(tc6->netdev, "STS0 register read failed.\n");
> + return ret;
> + }
> + if (regval & TXPE)
> + netdev_err(tc6->netdev, "Transmit protocol error\n");
> + if (regval & TXBOE)
> + netdev_err(tc6->netdev, "Transmit buffer overflow\n");
> + if (regval & TXBUE)
> + netdev_err(tc6->netdev, "Transmit buffer underflow\n");
> + if (regval & RXBOE)
> + netdev_err(tc6->netdev, "Receive buffer overflow\n");
> + if (regval & LOFE)
> + netdev_err(tc6->netdev, "Loss of frame\n");
> + if (regval & HDRE)
> + netdev_err(tc6->netdev, "Header error\n");
> + if (regval & TXFCSE)
> + netdev_err(tc6->netdev, "Transmit Frame Check Sequence Error\n");
> + ret = oa_tc6_write_register(tc6, OA_TC6_STS0, &regval, 1);
> + if (ret)
> + netdev_err(tc6->netdev, "STS0 register write failed.\n");
> + return ret;
> +}
> +
> +static int oa_tc6_process_rx_chunks(struct oa_tc6 *tc6, u8 *buf, u16 len)
> +{
> + u8 cp_count;
> + u8 *payload;
> + u32 ftr;
> + u16 ebo;
> + u16 sbo;
> +
> + /* Calculate the number of chunks received */
> + cp_count = len / (tc6->cps + TC6_FTR_SIZE);
> +
> + for (u8 i = 0; i < cp_count; i++) {
> + /* Get the footer and payload */
> + ftr = *(u32 *)&buf[tc6->cps + (i * (tc6->cps + TC6_FTR_SIZE))];
> + ftr = be32_to_cpu(ftr);
> + payload = &buf[(i * (tc6->cps + TC6_FTR_SIZE))];
> + /* Check for footer parity error */
> + if (oa_tc6_get_parity(ftr)) {
> + netdev_err(tc6->netdev, "Footer: Parity error\n");
> + goto err_exit;
> + }
> + /* If EXST set in the footer then read STS0 register to get the
> + * status information.
> + */
> + if (FIELD_GET(DATA_FTR_EXST, ftr)) {
> + if (oa_tc6_process_exst(tc6))
> + netdev_err(tc6->netdev, "Failed to process EXST\n");
> + goto err_exit;
> + }
> + if (FIELD_GET(DATA_FTR_HDRB, ftr)) {
> + netdev_err(tc6->netdev, "Footer: Received header bad\n");
> + goto err_exit;
> + }
> + if (!FIELD_GET(DATA_FTR_SYNC, ftr)) {
> + netdev_err(tc6->netdev, "Footer: Configuration unsync\n");
> + goto err_exit;
> + }
> + /* If Frame Drop is set, indicates that the MAC has detected a
> + * condition for which the SPI host should drop the received
> + * ethernet frame.
> + */
> + if (FIELD_GET(DATA_FTR_FD, ftr) && FIELD_GET(DATA_FTR_EV, ftr)) {
> + netdev_warn(tc6->netdev, "Footer: Frame drop\n");
> + if (FIELD_GET(DATA_FTR_SV, ftr)) {
> + goto start_new_frame;
> + } else {
> + if (tc6->rx_eth_started) {
> + tc6->rxd_bytes = 0;
> + tc6->rx_eth_started = false;
> + tc6->netdev->stats.rx_dropped++;
> + }
> + continue;
> + }
> + }
> + /* Check for data valid */
> + if (FIELD_GET(DATA_FTR_DV, ftr)) {
> + /* Check whether both start valid and end valid are in a
> + * single chunk payload means a single chunk payload may
> + * contain an entire ethernet frame.
> + */
> + if (FIELD_GET(DATA_FTR_SV, ftr) &&
> + FIELD_GET(DATA_FTR_EV, ftr)) {
> + sbo = FIELD_GET(DATA_FTR_SWO, ftr) * 4;
> + ebo = FIELD_GET(DATA_FTR_EBO, ftr) + 1;
> + if (ebo <= sbo) {
> + memcpy(&tc6->eth_rx_buf[tc6->rxd_bytes],
> + &payload[0], ebo);
> + tc6->rxd_bytes += ebo;
> + oa_tc6_rx_eth_ready(tc6);
> + tc6->rxd_bytes = 0;
> + memcpy(&tc6->eth_rx_buf[tc6->rxd_bytes],
> + &payload[sbo], tc6->cps - sbo);
> + tc6->rxd_bytes += (tc6->cps - sbo);
> + goto exit;
> + } else {
> + memcpy(&tc6->eth_rx_buf[tc6->rxd_bytes],
> + &payload[sbo], ebo - sbo);
> + tc6->rxd_bytes += (ebo - sbo);
> + oa_tc6_rx_eth_ready(tc6);
> + tc6->rxd_bytes = 0;
> + goto exit;
> + }
> + }
> +start_new_frame:
> + /* Check for start valid to start capturing the incoming
> + * ethernet frame.
> + */
> + if (FIELD_GET(DATA_FTR_SV, ftr) && !tc6->rx_eth_started) {
> + tc6->rxd_bytes = 0;
> + tc6->rx_eth_started = true;
> + sbo = FIELD_GET(DATA_FTR_SWO, ftr) * 4;
> + memcpy(&tc6->eth_rx_buf[tc6->rxd_bytes],
> + &payload[sbo], tc6->cps - sbo);
> + tc6->rxd_bytes += (tc6->cps - sbo);
> + goto exit;
> + }
> +
> + /* Check for end valid and calculate the copy length */
> + if (tc6->rx_eth_started) {
> + if (FIELD_GET(DATA_FTR_EV, ftr))
> + ebo = FIELD_GET(DATA_FTR_EBO, ftr) + 1;
> + else
> + ebo = tc6->cps;
> +
> + memcpy(&tc6->eth_rx_buf[tc6->rxd_bytes],
> + &payload[0], ebo);
> + tc6->rxd_bytes += ebo;
> + if (FIELD_GET(DATA_FTR_EV, ftr)) {
> + /* If End Valid set then send the
> + * received ethernet frame to n/w.
> + */
> + oa_tc6_rx_eth_ready(tc6);
> + tc6->rxd_bytes = 0;
> + tc6->rx_eth_started = false;
> + }
> + }
> + }
> +
> +exit:
> + tc6->txc = FIELD_GET(DATA_FTR_TXC, ftr);
> + tc6->rca = FIELD_GET(DATA_FTR_RCA, ftr);
> + }
> + return FTR_OK;
> +
> +err_exit:
> + if (tc6->rx_eth_started) {
> + tc6->rxd_bytes = 0;
> + tc6->rx_eth_started = false;
> + tc6->netdev->stats.rx_dropped++;
> + }
> + return FTR_ERR;
> +}
> +
> static int oa_tc6_handler(void *data)
> {
> struct oa_tc6 *tc6 = data;
> + bool txc_wait = false;
> + u16 tx_pos = 0;
> u32 regval;
> + u16 len;
> int ret;
>
> while (likely(!kthread_should_stop())) {
> - wait_event_interruptible(tc6->tc6_wq, tc6->int_flag ||
> + wait_event_interruptible(tc6->tc6_wq, tc6->tx_flag ||
> + tc6->int_flag || tc6->rca ||
> kthread_should_stop());
> - if (tc6->int_flag) {
> + if (tc6->int_flag && !tc6->reset) {
> tc6->int_flag = false;
> + tc6->reset = true;
> ret = oa_tc6_perform_ctrl(tc6, OA_TC6_STS0, &regval, 1,
> false, false);
> if (ret) {
> @@ -227,10 +435,170 @@ static int oa_tc6_handler(void *data)
> complete(&tc6->rst_complete);
> }
> }
> +
> + if (tc6->int_flag || tc6->rca) {
> + /* If rca is updated from the previous footer then
> + * prepare the empty chunks equal to rca and perform
> + * SPI transfer to receive the ethernet frame.
> + */
> + if (tc6->rca) {
> + len = oa_tc6_prepare_empty_chunk(tc6,
> + tc6->spi_tx_buf,
> + tc6->rca);
> + } else {
> + /* If there is an interrupt then perform a SPI
> + * transfer with a empty chunk to get the
> + * details.
> + */
> + tc6->int_flag = false;
> + len = oa_tc6_prepare_empty_chunk(tc6,
> + tc6->spi_tx_buf,
> + 1);
> + }
> + /* Perform SPI transfer */
> + ret = oa_tc6_spi_transfer(tc6->spi, tc6->spi_tx_buf,
> + tc6->spi_rx_buf, len);
> + if (ret) {
> + netdev_err(tc6->netdev, "SPI transfer failed\n");
> + continue;
> + }
> + /* Process the received chunks to get the ethernet frame
> + * or interrupt details.
> + */
> + if (oa_tc6_process_rx_chunks(tc6, tc6->spi_rx_buf, len))
> + continue;
> + }
> +
> + /* If there is a tx ethernet frame available */
> + if (tc6->tx_flag || txc_wait) {
> + tc6->tx_flag = false;
> + txc_wait = false;
> + len = 0;
> + if (!tc6->txc) {
> + /* If there is no txc available to transport the
> + * tx ethernet frames then wait for the MAC-PHY
> + * interrupt to get the txc availability.
> + */
> + txc_wait = true;
> + continue;
> + } else if (tc6->txc >= tc6->txc_needed) {
> + len = tc6->txc_needed * (tc6->cps + TC6_HDR_SIZE);
> + } else {
> + len = tc6->txc * (tc6->cps + TC6_HDR_SIZE);
> + }
> + memcpy(&tc6->spi_tx_buf[0], &tc6->eth_tx_buf[tx_pos],
> + len);
> + ret = oa_tc6_spi_transfer(tc6->spi, tc6->spi_tx_buf,
> + tc6->spi_rx_buf, len);
> + if (ret) {
> + netdev_err(tc6->netdev, "SPI transfer failed\n");
> + continue;
> + }
> + /* Process the received chunks to get the ethernet frame
> + * or status.
> + */
> + if (oa_tc6_process_rx_chunks(tc6, tc6->spi_rx_buf,
> + len)) {
> + /* In case of error while processing rx chunks
> + * discard the incomplete tx ethernet frame and
> + * resend it.
> + */
> + tx_pos = 0;
> + tc6->txc_needed = tc6->total_txc_needed;
> + } else {
> + tx_pos += len;
> + tc6->txc_needed = tc6->txc_needed -
> + (len / (tc6->cps + TC6_HDR_SIZE));
> + /* If the complete ethernet frame is transmitted
> + * then return the skb and update the details to
> + * n/w layer.
> + */
> + if (!tc6->txc_needed) {
> + tc6->netdev->stats.tx_packets++;
> + tc6->netdev->stats.tx_bytes += tc6->tx_skb->len;
> + dev_kfree_skb(tc6->tx_skb);
> + tx_pos = 0;
> + tc6->tx_skb = NULL;
> + if (netif_queue_stopped(tc6->netdev))
> + netif_wake_queue(tc6->netdev);
> + } else if (tc6->txc) {
> + /* If txc is available again and updated
> + * from the previous footer then perform
> + * tx again.
> + */
> + tc6->tx_flag = true;
> + } else {
> + /* If there is no txc then wait for the
> + * interrupt to indicate txc
> + * availability.
> + */
> + txc_wait = true;
> + }
> + }
> + }
> }
> return 0;
> }
>
> +static void oa_tc6_prepare_tx_chunks(struct oa_tc6 *tc6, u8 *buf,
> + struct sk_buff *skb)
> +{
> + bool frame_started = false;
> + u16 copied_bytes = 0;
> + u16 copy_len;
> + u32 hdr;
> +
> + /* Calculate the number tx credit counts needed to transport the tx
> + * ethernet frame.
> + */
> + tc6->txc_needed = (skb->len / tc6->cps) + ((skb->len % tc6->cps) ? 1 : 0);
> + tc6->total_txc_needed = tc6->txc_needed;
> +
> + for (u8 i = 0; i < tc6->txc_needed; i++) {
> + /* Prepare the header for each chunks to be transmitted */
> + hdr = FIELD_PREP(DATA_HDR_DNC, 1) |
> + FIELD_PREP(DATA_HDR_DV, 1);
> + if (!frame_started) {
> + hdr |= FIELD_PREP(DATA_HDR_SV, 1) |
> + FIELD_PREP(DATA_HDR_SWO, 0);
> + frame_started = true;
> + }
> + if ((tc6->cps + copied_bytes) >= skb->len) {
> + copy_len = skb->len - copied_bytes;
> + hdr |= FIELD_PREP(DATA_HDR_EBO, copy_len - 1) |
> + FIELD_PREP(DATA_HDR_EV, 1);
> + } else {
> + copy_len = tc6->cps;
> + }
> + copied_bytes += copy_len;
> + hdr |= FIELD_PREP(DATA_HDR_P, oa_tc6_get_parity(hdr));
> + hdr = cpu_to_be32(hdr);
> + *(u32 *)&buf[i * (tc6->cps + TC6_HDR_SIZE)] = hdr;
> + /* Copy the ethernet frame in the chunk payload section */
> + memcpy(&buf[TC6_HDR_SIZE + (i * (tc6->cps + TC6_HDR_SIZE))],
> + &skb->data[copied_bytes - copy_len], copy_len);
> + }
> +}
> +
> +netdev_tx_t oa_tc6_send_eth_pkt(struct oa_tc6 *tc6, struct sk_buff *skb)
> +{
> + if (tc6->tx_skb) {
> + netif_stop_queue(tc6->netdev);
> + return NETDEV_TX_BUSY;
> + }
> +
> + tc6->tx_skb = skb;
> + /* Prepare tx chunks using the tx ethernet frame */
> + oa_tc6_prepare_tx_chunks(tc6, tc6->eth_tx_buf, skb);
> +
> + /* Wake tc6 task to perform tx transfer */
> + tc6->tx_flag = true;
> + wake_up_interruptible(&tc6->tc6_wq);
> +
> + return NETDEV_TX_OK;
> +}
> +EXPORT_SYMBOL_GPL(oa_tc6_send_eth_pkt);
> +
> static irqreturn_t macphy_irq(int irq, void *dev_id)
> {
> struct oa_tc6 *tc6 = dev_id;
> @@ -293,6 +661,14 @@ int oa_tc6_configure(struct oa_tc6 *tc6, u8 cps, bool ctrl_prot, bool tx_cut_thr
> u32 regval;
> int ret;
>
> + /* Read BUFSTS register to get the current txc and rca. */
> + ret = oa_tc6_read_register(tc6, OA_TC6_BUFSTS, &regval, 1);
> + if (ret)
> + return ret;
> +
> + tc6->txc = FIELD_GET(TXC, regval);
> + tc6->rca = FIELD_GET(RCA, regval);
> +
> /* Read and configure the IMASK0 register for unmasking the interrupts */
> ret = oa_tc6_read_register(tc6, OA_TC6_IMASK0, &regval, 1);
> if (ret)
> @@ -326,7 +702,7 @@ int oa_tc6_configure(struct oa_tc6 *tc6, u8 cps, bool ctrl_prot, bool tx_cut_thr
> }
> EXPORT_SYMBOL_GPL(oa_tc6_configure);
>
> -struct oa_tc6 *oa_tc6_init(struct spi_device *spi)
> +struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev)
> {
> struct oa_tc6 *tc6;
> int ret;
> @@ -334,11 +710,39 @@ struct oa_tc6 *oa_tc6_init(struct spi_device *spi)
> if (!spi)
> return NULL;
>
> + if (!netdev)
> + return NULL;
> +
> tc6 = kzalloc(sizeof(*tc6), GFP_KERNEL);
> if (!tc6)
> return NULL;
>
> tc6->spi = spi;
> + tc6->netdev = netdev;
> +
> + /* Allocate memory for the tx buffer used for SPI transfer. */
> + tc6->spi_tx_buf = kzalloc(MAX_ETH_LEN + (OA_TC6_MAX_CPS * TC6_HDR_SIZE),
> + GFP_KERNEL);
> + if (!tc6->spi_tx_buf)
> + goto err_spi_tx_buf_alloc;
> +
> + /* Allocate memory for the rx buffer used for SPI transfer. */
> + tc6->spi_rx_buf = kzalloc(MAX_ETH_LEN + (OA_TC6_MAX_CPS * TC6_FTR_SIZE),
> + GFP_KERNEL);
> + if (!tc6->spi_rx_buf)
> + goto err_spi_rx_buf_alloc;
> +
> + /* Allocate memory for the tx ethernet chunks to transfer on SPI. */
> + tc6->eth_tx_buf = kzalloc(MAX_ETH_LEN + (OA_TC6_MAX_CPS * TC6_HDR_SIZE),
> + GFP_KERNEL);
> + if (!tc6->eth_tx_buf)
> + goto err_eth_tx_buf_alloc;
> +
> + /* Allocate memory for the rx ethernet packet. */
> + tc6->eth_rx_buf = kzalloc(MAX_ETH_LEN + (OA_TC6_MAX_CPS * TC6_FTR_SIZE),
> + GFP_KERNEL);
> + if (!tc6->eth_rx_buf)
> + goto err_eth_rx_buf_alloc;
>
> /* Used for triggering the OA TC6 task */
> init_waitqueue_head(&tc6->tc6_wq);
> @@ -372,6 +776,14 @@ struct oa_tc6 *oa_tc6_init(struct spi_device *spi)
> err_macphy_irq:
> kthread_stop(tc6->tc6_task);
> err_tc6_task:
> + kfree(tc6->eth_rx_buf);
> +err_eth_rx_buf_alloc:
> + kfree(tc6->eth_tx_buf);
> +err_eth_tx_buf_alloc:
> + kfree(tc6->spi_rx_buf);
> +err_spi_rx_buf_alloc:
> + kfree(tc6->spi_tx_buf);
> +err_spi_tx_buf_alloc:
> kfree(tc6);
> return NULL;
> }
> @@ -383,8 +795,13 @@ int oa_tc6_deinit(struct oa_tc6 *tc6)
>
> devm_free_irq(&tc6->spi->dev, tc6->spi->irq, tc6);
> ret = kthread_stop(tc6->tc6_task);
> - if (!ret)
> + if (!ret) {
> + kfree(tc6->eth_rx_buf);
> + kfree(tc6->eth_tx_buf);
> + kfree(tc6->spi_rx_buf);
> + kfree(tc6->spi_tx_buf);
> kfree(tc6);
> + }
> return ret;
> }
> EXPORT_SYMBOL_GPL(oa_tc6_deinit);
> diff --git a/include/linux/oa_tc6.h b/include/linux/oa_tc6.h
> index fa29c4e09720..61ac1cdfa7d6 100644
> --- a/include/linux/oa_tc6.h
> +++ b/include/linux/oa_tc6.h
> @@ -6,6 +6,7 @@
> */
>
> #include <linux/spi/spi.h>
> +#include <linux/netdevice.h>
>
> /* Control header */
> #define CTRL_HDR_DNC BIT(31) /* Data-Not-Control */
> @@ -17,10 +18,36 @@
> #define CTRL_HDR_LEN GENMASK(7, 1) /* Length */
> #define CTRL_HDR_P BIT(0) /* Parity Bit */
>
> +/* Data header */
> +#define DATA_HDR_DNC BIT(31) /* Data-Not-Control */
> +#define DATA_HDR_SEQ BIT(30) /* Data Chunk Sequence */
> +#define DATA_HDR_NORX BIT(29) /* No Receive */
> +#define DATA_HDR_DV BIT(21) /* Data Valid */
> +#define DATA_HDR_SV BIT(20) /* Start Valid */
> +#define DATA_HDR_SWO GENMASK(19, 16) /* Start Word Offset */
> +#define DATA_HDR_EV BIT(14) /* End Valid */
> +#define DATA_HDR_EBO GENMASK(13, 8) /* End Byte Offset */
> +#define DATA_HDR_P BIT(0) /* Header Parity Bit */
> +
> +/* Data footer */
> +#define DATA_FTR_EXST BIT(31) /* Extended Status */
> +#define DATA_FTR_HDRB BIT(30) /* Received Header Bad */
> +#define DATA_FTR_SYNC BIT(29) /* Configuration Synchronized */
> +#define DATA_FTR_RCA GENMASK(28, 24) /* Receive Chunks Available */
> +#define DATA_FTR_DV BIT(21) /* Data Valid */
> +#define DATA_FTR_SV BIT(20) /* Start Valid */
> +#define DATA_FTR_SWO GENMASK(19, 16) /* Start Word Offset */
> +#define DATA_FTR_FD BIT(15) /* Frame Drop */
> +#define DATA_FTR_EV BIT(14) /* End Valid */
> +#define DATA_FTR_EBO GENMASK(13, 8) /* End Byte Offset */
> +#define DATA_FTR_TXC GENMASK(5, 1) /* Transmit Credits */
> +#define DATA_FTR_P BIT(0) /* Footer Parity Bit */
> +
> /* Open Alliance TC6 Standard Control and Status Registers */
> #define OA_TC6_RESET 0x0003 /* Reset Control and Status Register */
> #define OA_TC6_CONFIG0 0x0004 /* Configuration Register #0 */
> #define OA_TC6_STS0 0x0008 /* Status Register #0 */
> +#define OA_TC6_BUFSTS 0x000B /* Buffer Status Register */
> #define OA_TC6_IMASK0 0x000C /* Interrupt Mask Register #0 */
>
> /* RESET register field */
> @@ -33,6 +60,17 @@
> #define PROTE BIT(5) /* Ctrl read/write Protection Enable */
> #define CPS GENMASK(2, 0) /* Chunk Payload Size */
>
> +/* STATUS0 register fields */
> +#define CDPE BIT(12) /* Control Data Protection Error */
> +#define TXFCSE BIT(11) /* Transmit Frame Check Sequence Error */
> +#define RESETC BIT(6) /* Reset Complete */
> +#define HDRE BIT(5) /* Header Error */
> +#define LOFE BIT(4) /* Loss of Framing Error */
> +#define RXBOE BIT(3) /* Receive Buffer Overflow Error */
> +#define TXBUE BIT(2) /* Transmit Buffer Underflow Error */
> +#define TXBOE BIT(1) /* Transmit Buffer Overflow Error */
> +#define TXPE BIT(0) /* Transmit Protocol Error */
> +
> /* Unmasking interrupt fields in IMASK0 */
> #define HDREM ~BIT(5) /* Header Error Mask */
> #define LOFEM ~BIT(4) /* Loss of Framing Error Mask */
> @@ -44,24 +82,49 @@
> /* STATUS0 register field */
> #define RESETC BIT(6) /* Reset Complete */
>
> +/* BUFSTS register fields */
> +#define TXC GENMASK(15, 8) /* Transmit Credits Available */
> +#define RCA GENMASK(7, 0) /* Receive Chunks Available */
> +
> #define TC6_HDR_SIZE 4 /* Ctrl command header size as per OA */
> #define TC6_FTR_SIZE 4 /* Ctrl command footer size ss per OA */
>
> +#define FTR_OK 0
> +#define FTR_ERR 1
> +
> +#define MAX_ETH_LEN 1536
> +#define OA_TC6_MAX_CPS 64
> +
> struct oa_tc6 {
> struct completion rst_complete;
> struct task_struct *tc6_task;
> + struct net_device *netdev;
> wait_queue_head_t tc6_wq;
> struct spi_device *spi;
> + struct sk_buff *tx_skb;
> + u8 total_txc_needed;
> + bool rx_eth_started;
> bool tx_cut_thr;
> bool rx_cut_thr;
> bool ctrl_prot;
> + u8 *spi_tx_buf;
> + u8 *spi_rx_buf;
> + u8 *eth_tx_buf;
> + u8 *eth_rx_buf;
> bool int_flag;
> + u16 rxd_bytes;
> + u8 txc_needed;
> + bool tx_flag;
> + bool reset;
> u8 cps;
> + u8 txc;
> + u8 rca;
> };
>
> -struct oa_tc6 *oa_tc6_init(struct spi_device *spi);
> +struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev);
> int oa_tc6_deinit(struct oa_tc6 *tc6);
> int oa_tc6_write_register(struct oa_tc6 *tc6, u32 addr, u32 value[], u8 len);
> int oa_tc6_read_register(struct oa_tc6 *tc6, u32 addr, u32 value[], u8 len);
> int oa_tc6_configure(struct oa_tc6 *tc6, u8 cps, bool ctrl_prot, bool tx_cut_thr,
> bool rx_cut_thr);
> +netdev_tx_t oa_tc6_send_eth_pkt(struct oa_tc6 *tc6, struct sk_buff *skb);
>