Re: [PATCH net-next v3 07/19] net: ravb: Move reference clock enable/disable on runtime PM APIs

From: Sergey Shtylyov
Date: Fri Jan 05 2024 - 14:52:41 EST


On 1/5/24 11:23 AM, Claudiu wrote:

> From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>
> Reference clock could be or not part of the power domain. If it is part of
> the power domain, the power domain takes care of propertly setting it. In
> case it is not part of the power domain and full runtime PM support is
> available in driver the clock will not be propertly disabled/enabled at
> runtime. For this, keep the prepare/unprepare operations in the driver's
> probe()/remove() functions and move the enable/disable in runtime PM
> functions.
>
> Along with it, the other clock request operations were moved close to
> reference clock request and prepare to have all the clock requests
> specific code grouped together.
>
> Reviewed-by: Sergey Shtylyov <s.shtylyov@xxxxxx>

It's not that I reviewed the squashed version of this patch...

> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
> ---
>
> Changes in v3:
> - squashed with patch 17/21 ("net: ravb: Keep clock request operations grouped
> together") from v2
> - collected tags
>
> Changes in v2:
> - this patch is new and follows the recommendations proposed in the
> discussion of patch 08/13 ("net: ravb: Rely on PM domain to enable refclk")
> from v2
>
> drivers/net/ethernet/renesas/ravb_main.c | 110 ++++++++++++-----------
> 1 file changed, 57 insertions(+), 53 deletions(-)
>
> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
> index 844ac3306e93..4673cc2faec0 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
[...]
> @@ -2697,10 +2692,37 @@ static int ravb_probe(struct platform_device *pdev)
> priv->num_rx_ring[RAVB_NC] = NC_RX_RING_SIZE;
> }
>
> + priv->clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(priv->clk)) {
> + error = PTR_ERR(priv->clk);
> + goto out_reset_assert;
> + }
> +
> + if (info->gptp_ref_clk) {
> + priv->gptp_clk = devm_clk_get(&pdev->dev, "gptp");
> + if (IS_ERR(priv->gptp_clk)) {
> + error = PTR_ERR(priv->gptp_clk);
> + goto out_reset_assert;
> + }
> + }
> +
> + priv->refclk = devm_clk_get_optional(&pdev->dev, "refclk");
> + if (IS_ERR(priv->refclk)) {
> + error = PTR_ERR(priv->refclk);
> + goto out_reset_assert;
> + }
> + clk_prepare(priv->refclk);
> +
> + platform_set_drvdata(pdev, ndev);

Why exactly you had to move this line?

> + pm_runtime_enable(&pdev->dev);
> + error = pm_runtime_resume_and_get(&pdev->dev);
> + if (error < 0)
> + goto out_rpm_disable;
> +
> priv->addr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
> if (IS_ERR(priv->addr)) {
> error = PTR_ERR(priv->addr);
> - goto out_release;
> + goto out_rpm_put;
> }
>
> /* The Ether-specific entries in the device structure. */
[...]
> @@ -2871,8 +2872,6 @@ static int ravb_probe(struct platform_device *pdev)
> netdev_info(ndev, "Base address at %#x, %pM, IRQ %d.\n",
> (u32)ndev->base_addr, ndev->dev_addr, ndev->irq);
>
> - platform_set_drvdata(pdev, ndev);

Hm, wasn't calling it here racy?

> -
> return 0;
>
> out_napi_del:
[...]
> @@ -3060,21 +3058,27 @@ static int ravb_resume(struct device *dev)
> return ret;
> }
>
> -static int ravb_runtime_nop(struct device *dev)
> +static int ravb_runtime_suspend(struct device *dev)
> {
> - /* Runtime PM callback shared between ->runtime_suspend()
> - * and ->runtime_resume(). Simply returns success.
> - *
> - * This driver re-initializes all registers after
> - * pm_runtime_get_sync() anyway so there is no need
> - * to save and restore registers here.
> - */

Perhaps even worth a separate patch to completely remove this function
which doesn't seem to make sense?

[...]

MBR, Sergey