From 6baa785a9c336f69c2aa36f4949856b3bb90bde3 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Thu, 23 Mar 2017 10:36:47 -0700 Subject: [PATCH] net: systemport: Clear status to reduce spurious interrupts Do something similar to commit d5810ca3252a ("net: bcmgenet: clear status to reduce spurious interrupts") and clear interrupts right before servicing them. This reduces the number of interrupts by 10K interrupts/sec for a TX TCP session 1Gbits/sec. Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bcmsysport.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c index 986fb05529fc..c915bcfae0af 100644 --- a/drivers/net/ethernet/broadcom/bcmsysport.c +++ b/drivers/net/ethernet/broadcom/bcmsysport.c @@ -669,6 +669,9 @@ static unsigned int bcm_sysport_desc_rx(struct bcm_sysport_priv *priv, u16 len, status; struct bcm_rsb *rsb; + /* Clear status before servicing to reduce spurious interrupts */ + intrl2_0_writel(priv, INTRL2_0_RDMA_MBDONE, INTRL2_CPU_CLEAR); + /* Determine how much we should process since last call, SYSTEMPORT Lite * groups the producer and consumer indexes into the same 32-bit * which we access using RDMA_CONS_INDEX @@ -814,6 +817,13 @@ static unsigned int __bcm_sysport_tx_reclaim(struct bcm_sysport_priv *priv, struct bcm_sysport_cb *cb; u32 hw_ind; + /* Clear status before servicing to reduce spurious interrupts */ + if (!ring->priv->is_lite) + intrl2_1_writel(ring->priv, BIT(ring->index), INTRL2_CPU_CLEAR); + else + intrl2_0_writel(ring->priv, BIT(ring->index + + INTRL2_0_TDMA_MBDONE_SHIFT), INTRL2_CPU_CLEAR); + /* Compute how many descriptors have been processed since last call */ hw_ind = tdma_readl(priv, TDMA_DESC_RING_PROD_CONS_INDEX(ring->index)); c_index = (hw_ind >> RING_CONS_INDEX_SHIFT) & RING_CONS_INDEX_MASK; -- 2.20.1