diff options
Diffstat (limited to 'target/linux/layerscape/patches-5.4/802-can-0008-can-flexcan-flexcan_irq_state-only-read-timestamp-if.patch')
-rw-r--r-- | target/linux/layerscape/patches-5.4/802-can-0008-can-flexcan-flexcan_irq_state-only-read-timestamp-if.patch | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/target/linux/layerscape/patches-5.4/802-can-0008-can-flexcan-flexcan_irq_state-only-read-timestamp-if.patch b/target/linux/layerscape/patches-5.4/802-can-0008-can-flexcan-flexcan_irq_state-only-read-timestamp-if.patch new file mode 100644 index 0000000000..bc84f5f907 --- /dev/null +++ b/target/linux/layerscape/patches-5.4/802-can-0008-can-flexcan-flexcan_irq_state-only-read-timestamp-if.patch @@ -0,0 +1,38 @@ +From 1a92e5a9109963e2491eec111b84b35b4e2adc8f Mon Sep 17 00:00:00 2001 +From: Marc Kleine-Budde <mkl@pengutronix.de> +Date: Wed, 9 Oct 2019 15:15:37 +0200 +Subject: [PATCH] can: flexcan: flexcan_irq_state(): only read timestamp if + needed + +The function flexcan_irq_state() checks the controller for CAN state +changes and pushes a skb with the new state and a timestamp into the +rx-offload framework. + +This patch optimizes the function by only reading the timestamp, if a +state change is detected. + +Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> +--- + drivers/net/can/flexcan.c | 4 ++-- + 1 file changed, 2 insertions(+), 2 deletions(-) + +--- a/drivers/net/can/flexcan.c ++++ b/drivers/net/can/flexcan.c +@@ -744,8 +744,6 @@ static void flexcan_irq_state(struct net + u32 timestamp; + int err; + +- timestamp = priv->read(®s->timer) << 16; +- + flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK; + if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) { + tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ? +@@ -765,6 +763,8 @@ static void flexcan_irq_state(struct net + if (likely(new_state == priv->can.state)) + return; + ++ timestamp = priv->read(®s->timer) << 16; ++ + skb = alloc_can_err_skb(dev, &cf); + if (unlikely(!skb)) + return; |