[PATCH net] net: broadcom: bcm4908_enet: enable RX after processing packets

From: Rafał Miłecki <rafal@milecki.pl>

When receiving a lot of packets hardware may run out of free
descriptiors and stop RX ring. Enable it every time after handling
received packets.

Fixes: 4feffeadbcb2 ("net: broadcom: bcm4908enet: add BCM4908 controller driver")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
 drivers/net/ethernet/broadcom/bcm4908_enet.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bcm4908_enet.c b/drivers/net/ethernet/broadcom/bcm4908_enet.c
index 0b70e9e0ddad..98cf82dea3e4 100644
--- a/drivers/net/ethernet/broadcom/bcm4908_enet.c
+++ b/drivers/net/ethernet/broadcom/bcm4908_enet.c

@@ -592,6 +592,9 @@ static int bcm4908_enet_poll(struct napi_struct *napi, int weight)
 		bcm4908_enet_intrs_on(enet);
 	}
 
+	/* Hardware could disable ring if it run out of descriptors */
+	bcm4908_enet_dma_rx_ring_enable(enet, &enet->rx_ring);
+
 	return handled;
 }
 

-- 
2.26.2

On 2/26/2021 5:20 AM, Rafał Miłecki wrote:

From: Rafał Miłecki <rafal@milecki.pl>

When receiving a lot of packets hardware may run out of free
descriptiors and stop RX ring. Enable it every time after handling
received packets.

Fixes: 4feffeadbcb2 ("net: broadcom: bcm4908enet: add BCM4908 controller driver")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

On Sat, 27 Feb 2021 08:38:24 -0800 Florian Fainelli wrote:

On 2/26/2021 5:20 AM, Rafał Miłecki wrote:

quoted

From: Rafał Miłecki <rafal@milecki.pl>

When receiving a lot of packets hardware may run out of free
descriptiors and stop RX ring. Enable it every time after handling
received packets.

Fixes: 4feffeadbcb2 ("net: broadcom: bcm4908enet: add BCM4908 controller driver")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>  

Acked-by: Florian Fainelli <f.fainelli@gmail.com>

Applied, thanks!

Out of curiosity - is the performance not impacted by this change?
bcm4908_enet_dma_rx_ring_enable() does an RMW, the read could possibly
removed by caching the expected value.