From 6355a3c983e6d6fc998f4223bd2c7ef047e4572b Mon Sep 17 00:00:00 2001 From: Markus Schneider-Pargmann Date: Tue, 6 Dec 2022 12:57:22 +0100 Subject: can: m_can: Count read getindex in the driver The getindex gets increased by one every time. We can calculate the correct getindex in the driver and avoid the additional reads of rxfs. Signed-off-by: Markus Schneider-Pargmann Link: https://lore.kernel.org/all/20221206115728.1056014-6-msp@baylibre.com Signed-off-by: Marc Kleine-Budde --- drivers/net/can/m_can/m_can.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) (limited to 'drivers/net/can/m_can/m_can.c') diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 83d3a7f191bf..9476d96013fa 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -477,19 +477,16 @@ static void m_can_receive_skb(struct m_can_classdev *cdev, } } -static int m_can_read_fifo(struct net_device *dev, u32 rxfs) +static int m_can_read_fifo(struct net_device *dev, u32 fgi) { struct net_device_stats *stats = &dev->stats; struct m_can_classdev *cdev = netdev_priv(dev); struct canfd_frame *cf; struct sk_buff *skb; struct id_and_dlc fifo_header; - u32 fgi; u32 timestamp = 0; int err; - /* calculate the fifo get index for where to read data */ - fgi = FIELD_GET(RXFS_FGI_MASK, rxfs); err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_ID, &fifo_header, 2); if (err) goto out_fail; @@ -554,6 +551,9 @@ static int m_can_do_rx_poll(struct net_device *dev, int quota) struct m_can_classdev *cdev = netdev_priv(dev); u32 pkts = 0; u32 rxfs; + u32 rx_count; + u32 fgi; + int i; int err; rxfs = m_can_read(cdev, M_CAN_RXF0S); @@ -562,14 +562,17 @@ static int m_can_do_rx_poll(struct net_device *dev, int quota) return 0; } - while ((rxfs & RXFS_FFL_MASK) && (quota > 0)) { - err = m_can_read_fifo(dev, rxfs); + rx_count = FIELD_GET(RXFS_FFL_MASK, rxfs); + fgi = FIELD_GET(RXFS_FGI_MASK, rxfs); + + for (i = 0; i < rx_count && quota > 0; ++i) { + err = m_can_read_fifo(dev, fgi); if (err) return err; quota--; pkts++; - rxfs = m_can_read(cdev, M_CAN_RXF0S); + fgi = (++fgi >= cdev->mcfg[MRAM_RXF0].num ? 0 : fgi); } return pkts; -- cgit