RE: [PATCH net-next 13/13] ravb: Add reset support

Hi Sergei,

Thanks for the feedback.

Subject: Re: [PATCH net-next 13/13] ravb: Add reset support

On 8/25/21 10:01 AM, Biju Das wrote:

quoted

Reset support is present on R-Car. Let's support it, if it is
available.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

[...]

quoted

diff --git a/drivers/net/ethernet/renesas/ravb_main.c

b/drivers/net/ethernet/renesas/ravb_main.c
index 7a144b45e41d..0f85f2d97b18 100644

--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c

[...]

quoted

@@ -2349,6 +2358,7 @@ static int ravb_probe(struct platform_device

*pdev)

 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
+	reset_control_assert(rstc);
 	return error;
 }

@@ -2374,6 +2384,7 @@ static int ravb_remove(struct platform_device

*pdev)

quoted

 	netif_napi_del(&priv->napi[RAVB_BE]);
 	ravb_mdio_release(priv);
 	pm_runtime_disable(&pdev->dev);
+	reset_control_assert(priv->rstc);
 	free_netdev(ndev);
 	platform_set_drvdata(pdev, NULL);

   Is it possible to get into/out of reset in open()/close() methods?

No, Reason, Normally reset will be called

	ravb_mdio_release(priv);
	pm_runtime_disable(&pdev->dev);
	reset_control_assert(priv->rstc);

After reset assert, We should not access any RAVB registers, otherwise system will hang.
There is a high chance that other users(for eg:- mdio) may access ravb registers and system hangs.

Regards,
Biju

   Otherwise, looks good (I'm not much into reset h/w)

Reviewed-by: Sergey Shtylyov <redacted>

MBR, Sergey