From: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx> Transmit events from the txe fifo can be batch acknowledged by acknowledging the last read txe fifo item. This will save txe_count writes which is important for peripheral chips. Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx> Link: https://lore.kernel.org/all/20221206115728.1056014-7-msp@xxxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- drivers/net/can/m_can/m_can.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 9476d96013fa..656d2daafad1 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1023,7 +1023,9 @@ static int m_can_echo_tx_event(struct net_device *dev) u32 txe_count = 0; u32 m_can_txefs; u32 fgi = 0; + int ack_fgi = -1; int i = 0; + int err = 0; unsigned int msg_mark; struct m_can_classdev *cdev = netdev_priv(dev); @@ -1038,28 +1040,29 @@ static int m_can_echo_tx_event(struct net_device *dev) /* Get and process all sent elements */ for (i = 0; i < txe_count; i++) { u32 txe, timestamp = 0; - int err; /* get message marker, timestamp */ err = m_can_txe_fifo_read(cdev, fgi, 4, &txe); if (err) { netdev_err(dev, "TXE FIFO read returned %d\n", err); - return err; + break; } msg_mark = FIELD_GET(TX_EVENT_MM_MASK, txe); timestamp = FIELD_GET(TX_EVENT_TXTS_MASK, txe) << 16; - /* ack txe element */ - m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK, - fgi)); + ack_fgi = fgi; fgi = (++fgi >= cdev->mcfg[MRAM_TXE].num ? 0 : fgi); /* update stats */ m_can_tx_update_stats(cdev, msg_mark, timestamp); } - return 0; + if (ack_fgi != -1) + m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK, + ack_fgi)); + + return err; } static irqreturn_t m_can_isr(int irq, void *dev_id) -- 2.35.1
