[PATCH net-next v2 20/21] net: ravb: Do not apply RX CSUM settings to hardware if the interface is down

From: Claudiu
Date: Thu Dec 14 2023 - 06:48:12 EST


From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>

Do not apply the RX CSUM settings to hardware if the interface is down. In
case runtime PM is enabled, and while the interface is down, the IP will be
in reset mode (as for some platforms disabling/enabling the clocks will
switch the IP to standby mode, which will lead to losing registers'
content) and applying settings in reset mode is not an option. Instead,
cache the RX CSUM settings and apply them in ravb_open().

Commit prepares for the addition of runtime PM.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
---

Changes in v2:
- none; this patch is new

drivers/net/ethernet/renesas/ravb_main.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 633346b6cd7c..9ff943dff522 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -1868,6 +1868,15 @@ static int ravb_open(struct net_device *ndev)
if (info->gptp || info->ccc_gac)
ravb_ptp_init(ndev, priv->pdev);

+ /* Apply features that might have been changed while the interface
+ * was down.
+ */
+ if (ndev->hw_features & NETIF_F_RXCSUM) {
+ u32 val = (ndev->features & NETIF_F_RXCSUM) ? ECMR_RCSC : 0;
+
+ ravb_modify(ndev, ECMR, ECMR_RCSC, val);
+ }
+
/* PHY control start */
error = ravb_phy_start(ndev);
if (error)
@@ -2337,6 +2346,9 @@ static void ravb_set_rx_csum(struct net_device *ndev, bool enable)
struct ravb_private *priv = netdev_priv(ndev);
unsigned long flags;

+ if (!netif_running(ndev))
+ return;
+
spin_lock_irqsave(&priv->lock, flags);

/* Disable TX and RX */
--
2.39.2