[PATCH v2 04/11] can: m_can: Count TXE FIFO getidx in the driver

From: Markus Schneider-Pargmann
Date: Tue Dec 06 2022 - 06:58:01 EST


The getindex simply increases by one for every iteration. There is no
need to get the current getidx every time from a register. Instead we
can just count and wrap if necessary.

Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
---
drivers/net/can/m_can/m_can.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index 45c718413abf..a133f15fb90a 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -1020,15 +1020,13 @@ static int m_can_echo_tx_event(struct net_device *dev)

/* Get Tx Event fifo element count */
txe_count = FIELD_GET(TXEFS_EFFL_MASK, m_can_txefs);
+ fgi = FIELD_GET(TXEFS_EFGI_MASK, m_can_txefs);

/* Get and process all sent elements */
for (i = 0; i < txe_count; i++) {
u32 txe, timestamp = 0;
int err;

- /* retrieve get index */
- fgi = FIELD_GET(TXEFS_EFGI_MASK, m_can_read(cdev, M_CAN_TXEFS));
-
/* get message marker, timestamp */
err = m_can_txe_fifo_read(cdev, fgi, 4, &txe);
if (err) {
@@ -1042,6 +1040,7 @@ static int m_can_echo_tx_event(struct net_device *dev)
/* ack txe element */
m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK,
fgi));
+ fgi = (++fgi >= cdev->mcfg[MRAM_TXE].num ? 0 : fgi);

/* update stats */
m_can_tx_update_stats(cdev, msg_mark, timestamp);
--
2.38.1