[net-next,v3,18/19] net: ravb: Do not apply RX CSUM settings to hardware if the interface is down

Message ID 20240105082339.1468817-19-claudiu.beznea.uj@bp.renesas.com
State New
Headers
Series net: ravb: Add suspend to RAM and runtime PM support for RZ/G3S |

Commit Message

claudiu beznea Jan. 5, 2024, 8:23 a.m. UTC
  From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

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 the clocks will switch the
IP to reset 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() though ravb_emac_init().

Commit prepares for the addition of runtime PM.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
---

Changes in v3:
- this was patch 20/21 in v2
- fixed typos in patch description
- removed code from ravb_open()
- use ndev->flags & IFF_UP checks instead of netif_running()

Changes in v2:
- none; this patch is new


 drivers/net/ethernet/renesas/ravb_main.c | 3 +++
 1 file changed, 3 insertions(+)
  

Comments

Sergey Shtylyov Jan. 8, 2024, 8:34 p.m. UTC | #1
On 1/5/24 11:23 AM, Claudiu wrote:

> From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
> 
> 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 the clocks will switch the
> IP to reset 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() though ravb_emac_init().
> 
> Commit prepares for the addition of runtime PM.
> 
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
[...]

> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
> index 168b6208db37..e909960fbc30 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> @@ -2342,6 +2342,9 @@ static void ravb_set_rx_csum(struct net_device *ndev, bool enable)
>  	struct ravb_private *priv = netdev_priv(ndev);
>  	unsigned long flags;
>  
> +	if (!(ndev->flags & IFF_UP))

   Well, I guess it's even OK to even write EDCMR in the reset mode... BUT
again, won't this race with pm_runtime_put_autosuspend() when its call gets
added to ravb_close()?

> +		return;
> +
>  	spin_lock_irqsave(&priv->lock, flags);
>  
>  	/* Disable TX and RX */

MBR, Sergey
  
Sergey Shtylyov Jan. 8, 2024, 8:36 p.m. UTC | #2
On 1/8/24 11:34 PM, Sergey Shtylyov wrote:
[...]

>> From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
>>
>> 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 the clocks will switch the
>> IP to reset 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() though ravb_emac_init().
>>
>> Commit prepares for the addition of runtime PM.
>>
>> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
> [...]
> 
>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
>> index 168b6208db37..e909960fbc30 100644
>> --- a/drivers/net/ethernet/renesas/ravb_main.c
>> +++ b/drivers/net/ethernet/renesas/ravb_main.c
>> @@ -2342,6 +2342,9 @@ static void ravb_set_rx_csum(struct net_device *ndev, bool enable)
>>  	struct ravb_private *priv = netdev_priv(ndev);
>>  	unsigned long flags;
>>  
>> +	if (!(ndev->flags & IFF_UP))
> 
>    Well, I guess it's even OK to even write EDCMR in the reset mode... BUT

   Well, I guess it's even OK to write ECMR in the reset mode... :-)

> again, won't this race with pm_runtime_put_autosuspend() when its call gets
> added to ravb_close()?

[...]

MBR, Sergey
  
Sergey Shtylyov Jan. 8, 2024, 8:49 p.m. UTC | #3
On 1/5/24 11:23 AM, Claudiu wrote:

> From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
> 
> Do not apply the RX CSUM settings to hardware if the interface is down. In

   s/CSUM/checksum/?

> case runtime PM is enabled, and while the interface is down, the IP will be
> in reset mode (as for some platforms disabling the clocks will switch the
> IP to reset mode, which will lead to losing registers content) and applying
> settings in reset mode is not an option. Instead, cache the RX CSUM

   Same here...

> settings and apply them in ravb_open() though ravb_emac_init().

   Through?

> Commit prepares for the addition of runtime PM.
> 
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
[...]

MBR, Sergey
  

Patch

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 168b6208db37..e909960fbc30 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2342,6 +2342,9 @@  static void ravb_set_rx_csum(struct net_device *ndev, bool enable)
 	struct ravb_private *priv = netdev_priv(ndev);
 	unsigned long flags;
 
+	if (!(ndev->flags & IFF_UP))
+		return;
+
 	spin_lock_irqsave(&priv->lock, flags);
 
 	/* Disable TX and RX */