On 2/9/24 8:04 PM, Claudiu wrote:
> From: Claudiu Beznea <[email protected]>
>
> Do not apply the RX checksum 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 register contents) and
> applying settings in reset mode is not an option. Instead, cache the RX
> checksum settings and apply them in ravb_open() through ravb_emac_init().
> This has been solved by introducing pm_runtime_active() check. The device
> runtime PM usage counter has been incremented to avoid disabling the device
> clocks while the check is in progress (if any).
>
> Commit prepares for the addition of runtime PM.
>
> Signed-off-by: Claudiu Beznea <[email protected]>
Reviewed-by: Sergey Shtylyov <[email protected]>
[...]
MBR, Sergey
Hi Sergey,
> -----Original Message-----
> From: Sergey Shtylyov <[email protected]>
> Sent: Friday, February 9, 2024 8:27 PM
> Subject: Re: [PATCH net-next v2 4/5] net: ravb: Do not apply RX checksum
> settings to hardware if the interface is down
>
> On 2/9/24 8:04 PM, Claudiu wrote:
>
> > From: Claudiu Beznea <[email protected]>
> >
> > Do not apply the RX checksum 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 register
> > contents) and applying settings in reset mode is not an option.
> > Instead, cache the RX checksum settings and apply them in ravb_open()
> through ravb_emac_init().
> > This has been solved by introducing pm_runtime_active() check. The
> > device runtime PM usage counter has been incremented to avoid
> > disabling the device clocks while the check is in progress (if any).
> >
> > Commit prepares for the addition of runtime PM.
> >
> > Signed-off-by: Claudiu Beznea <[email protected]>
>
> Reviewed-by: Sergey Shtylyov <[email protected]>
This will do the same job, without code duplication right?
static int ravb_set_features(struct net_device *ndev,
netdev_features_t features)
{
struct ravb_private *priv = netdev_priv(ndev);
struct device *dev = &priv->pdev->dev;
const struct ravb_hw_info *info = priv->info;
pm_runtime_get_noresume(dev);
if (!pm_runtime_active(dev)) {
pm_runtime_put_noidle(dev);
ndev->features = features;
return 0;
}
return info->set_feature(ndev, features);
}
Cheers,
Biju
On 2/9/24 11:41 PM, Biju Das wrote:
[...]
>>> From: Claudiu Beznea <[email protected]>
>>>
>>> Do not apply the RX checksum 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 register
>>> contents) and applying settings in reset mode is not an option.
>>> Instead, cache the RX checksum settings and apply them in ravb_open()
>>> through ravb_emac_init().
>>> This has been solved by introducing pm_runtime_active() check. The
>>> device runtime PM usage counter has been incremented to avoid
>>> disabling the device clocks while the check is in progress (if any).
>>>
>>> Commit prepares for the addition of runtime PM.
>>>
>>> Signed-off-by: Claudiu Beznea <[email protected]>
>>
>> Reviewed-by: Sergey Shtylyov <[email protected]>
>
> This will do the same job, without code duplication right?
>
> static int ravb_set_features(struct net_device *ndev,
> netdev_features_t features)
> {
> struct ravb_private *priv = netdev_priv(ndev);
> struct device *dev = &priv->pdev->dev;
> const struct ravb_hw_info *info = priv->info;
>
> pm_runtime_get_noresume(dev);
> if (!pm_runtime_active(dev)) {
> pm_runtime_put_noidle(dev);
> ndev->features = features;
> return 0;
> }
>
> return info->set_feature(ndev, features);
We now leak the device reference by not calling pm_runtime_put_noidle()
after this statement...
The approach seems sane though -- Claudiu, please consider following it.
[...]
> Cheers,
> Biju
MBR, Sergey