Re: [PATCH 04/13] net: mvneta: enable suspend/resume support

Gregory CLEMENT
2015-11-25T18:35:40Z

Hi Marcin,

On dim., nov. 22 2015, Marcin Wojtas <mw@semihalf.com> wrote:

> This commit introduces suspend/resume routines used for both in 'standby'
> and 'mem' modes. For the latter, in which registers' contents are lost,
> following steps are performed:
> * in suspend - update port statistics and, if interface is running,
> detach netif, clean the queues, disable cpu notifier, shutdown
> interface and reset port's link status;
> * in resume, for all interfaces, set default configuration of the port and
> MBUS windows;
> * in resume, in case the interface is running, enable accepting packets in
> legacy parser, power up the port, register cpu notifier and attach
> netif.

I don't have the hardware to use suspend to RAM on Armada XP but at
least in standby the network continue to work on wakeup.

>
> Signed-off-by: Marcin Wojtas <mw@semihalf.com>
> ---
> drivers/net/ethernet/marvell/mvneta.c | 70 +++++++++++++++++++++++++++++++++++
> 1 file changed, 70 insertions(+)
>
> diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
> index d12b8c6..f079b13 100644
> --- a/drivers/net/ethernet/marvell/mvneta.c
> +++ b/drivers/net/ethernet/marvell/mvneta.c
> @@ -3442,6 +3442,72 @@ static int mvneta_remove(struct platform_device *pdev)
> return 0;
> }
>
> +#ifdef CONFIG_PM_SLEEP
> +static int mvneta_suspend(struct platform_device *pdev, pm_message_t state)
> +{
> + struct net_device *dev = platform_get_drvdata(pdev);
> + struct mvneta_port *pp = netdev_priv(dev);
> +
> + mvneta_ethtool_update_stats(pp);
> +
> + if (!netif_running(dev))
> + return 0;
> +
> + netif_device_detach(dev);
> +
> + mvneta_stop_dev(pp);
> + unregister_cpu_notifier(&pp->cpu_notifier);
> + mvneta_cleanup_rxqs(pp);
> + mvneta_cleanup_txqs(pp);
> +
> + /* Reset link status */
> + pp->link = 0;
> + pp->duplex = -1;
> + pp->speed = 0;
> +

Would it be possible to add a kind of mvneta_port_power_down(pp,
pp->phy_interface) here ? It would allow to save power in standby mode
too.

> + return 0;
> +}
> +
> +static int mvneta_resume(struct platform_device *pdev)
> +{
> + const struct mbus_dram_target_info *dram_target_info;
> + struct net_device *dev = platform_get_drvdata(pdev);
> + struct mvneta_port *pp = netdev_priv(dev);
> + int ret;
> +
> + mvneta_defaults_set(pp);
> + mvneta_port_power_up(pp, pp->phy_interface);
> +
> + dram_target_info = mv_mbus_dram_info();
> + if (dram_target_info)
> + mvneta_conf_mbus_windows(pp, dram_target_info);
> +
> + if (!netif_running(dev))
> + return 0;
> +
> + ret = mvneta_setup_rxqs(pp);
> + if (ret) {
> + netdev_err(dev, "unable to setup rxqs after resume\n");
> + return ret;
> + }
> +
> + ret = mvneta_setup_txqs(pp);
> + if (ret) {
> + netdev_err(dev, "unable to setup txqs after resume\n");
> + return ret;
> + }
> +
> + mvneta_set_rx_mode(dev);
> + mvneta_percpu_elect(pp);
> + register_cpu_notifier(&pp->cpu_notifier);
> + mvneta_start_dev(pp);
> +
> + netif_device_attach(dev);
> +
> + return 0;
> +}
> +#endif /* CONFIG_PM_SLEEP */
> +
> static const struct of_device_id mvneta_match[] = {
> { .compatible = "marvell,armada-370-neta" },
> { .compatible = "marvell,armada-xp-neta" },
> @@ -3452,6 +3518,10 @@ MODULE_DEVICE_TABLE(of, mvneta_match);
> static struct platform_driver mvneta_driver = {
> .probe = mvneta_probe,
> .remove = mvneta_remove,
> +#ifdef CONFIG_PM_SLEEP
> + .suspend = mvneta_suspend,
> + .resume = mvneta_resume,
> +#endif
> .driver = {
> .name = MVNETA_DRIVER_NAME,
> .of_match_table = mvneta_match,
> --
> 1.8.3.1
>

--
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.