@@ -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);
@@ -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);