Re: [PATCH 1/1] Revert "net: fec: Ensure clocks are enabled while using mdio bus"

[Lucas Stach <l.stach@pengutronix.de>]

Am Freitag, den 14.08.2015, 13:47 +0800 schrieb Peter Chen:
> It causes the i.mx6sx sdb board hang when using nfsroot during boots
> up at v4.2-rc6.
> 
> This reverts commit 8fff755e9f8d0f70a595e79f248695ce6aef5cc3.
> 
> Cc: netdev@vger.kernel.org
> Cc: Fugang Duan <B38611@freescale.com>
> Cc: shawn.guo@linaro.org
> Cc: fabio.estevam@freescale.com
> Cc: tyler.baker@linaro.org
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Peter Chen <peter.chen@freescale.com>
> ---
> 
> According to Fugang Duan, the i.mx series has different clock control
> sequence among SoCs, this patch may only consider certain SoCs.
> 
Sorry, but NACK.

Please test current mainline (what will become v4.2-rc7). There is
already a patch in that fixes i.MX27 and probably fixes the same problem
on i.MX6SX.

>  drivers/net/ethernet/freescale/fec_main.c | 89 +++++--------------------------
>  1 file changed, 13 insertions(+), 76 deletions(-)
> 
> diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
> index 32e3807c..5e8b837 100644
> --- a/drivers/net/ethernet/freescale/fec_main.c
> +++ b/drivers/net/ethernet/freescale/fec_main.c
> @@ -24,7 +24,6 @@
>  #include <linux/module.h>
>  #include <linux/kernel.h>
>  #include <linux/string.h>
> -#include <linux/pm_runtime.h>
>  #include <linux/ptrace.h>
>  #include <linux/errno.h>
>  #include <linux/ioport.h>
> @@ -78,7 +77,6 @@ static void fec_enet_itr_coal_init(struct net_device *ndev);
>  #define FEC_ENET_RAEM_V	0x8
>  #define FEC_ENET_RAFL_V	0x8
>  #define FEC_ENET_OPD_V	0xFFF0
> -#define FEC_MDIO_PM_TIMEOUT  100 /* ms */
>  
>  static struct platform_device_id fec_devtype[] = {
>  	{
> @@ -1769,13 +1767,7 @@ static void fec_enet_adjust_link(struct net_device *ndev)
>  static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
>  {
>  	struct fec_enet_private *fep = bus->priv;
> -	struct device *dev = &fep->pdev->dev;
>  	unsigned long time_left;
> -	int ret = 0;
> -
> -	ret = pm_runtime_get_sync(dev);
> -	if (IS_ERR_VALUE(ret))
> -		return ret;
>  
>  	fep->mii_timeout = 0;
>  	init_completion(&fep->mdio_done);
> @@ -1791,30 +1783,18 @@ static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
>  	if (time_left == 0) {
>  		fep->mii_timeout = 1;
>  		netdev_err(fep->netdev, "MDIO read timeout\n");
> -		ret = -ETIMEDOUT;
> -		goto out;
> +		return -ETIMEDOUT;
>  	}
>  
> -	ret = FEC_MMFR_DATA(readl(fep->hwp + FEC_MII_DATA));
> -
> -out:
> -	pm_runtime_mark_last_busy(dev);
> -	pm_runtime_put_autosuspend(dev);
> -
> -	return ret;
> +	/* return value */
> +	return FEC_MMFR_DATA(readl(fep->hwp + FEC_MII_DATA));
>  }
>  
>  static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
>  			   u16 value)
>  {
>  	struct fec_enet_private *fep = bus->priv;
> -	struct device *dev = &fep->pdev->dev;
>  	unsigned long time_left;
> -	int ret = 0;
> -
> -	ret = pm_runtime_get_sync(dev);
> -	if (IS_ERR_VALUE(ret))
> -		return ret;
>  
>  	fep->mii_timeout = 0;
>  	init_completion(&fep->mdio_done);
> @@ -1831,13 +1811,10 @@ static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
>  	if (time_left == 0) {
>  		fep->mii_timeout = 1;
>  		netdev_err(fep->netdev, "MDIO write timeout\n");
> -		ret  = -ETIMEDOUT;
> +		return -ETIMEDOUT;
>  	}
>  
> -	pm_runtime_mark_last_busy(dev);
> -	pm_runtime_put_autosuspend(dev);
> -
> -	return ret;
> +	return 0;
>  }
>  
>  static int fec_enet_clk_enable(struct net_device *ndev, bool enable)
> @@ -1849,6 +1826,9 @@ static int fec_enet_clk_enable(struct net_device *ndev, bool enable)
>  		ret = clk_prepare_enable(fep->clk_ahb);
>  		if (ret)
>  			return ret;
> +		ret = clk_prepare_enable(fep->clk_ipg);
> +		if (ret)
> +			goto failed_clk_ipg;
>  		if (fep->clk_enet_out) {
>  			ret = clk_prepare_enable(fep->clk_enet_out);
>  			if (ret)
> @@ -1872,6 +1852,7 @@ static int fec_enet_clk_enable(struct net_device *ndev, bool enable)
>  		}
>  	} else {
>  		clk_disable_unprepare(fep->clk_ahb);
> +		clk_disable_unprepare(fep->clk_ipg);
>  		if (fep->clk_enet_out)
>  			clk_disable_unprepare(fep->clk_enet_out);
>  		if (fep->clk_ptp) {
> @@ -1893,6 +1874,8 @@ failed_clk_ptp:
>  	if (fep->clk_enet_out)
>  		clk_disable_unprepare(fep->clk_enet_out);
>  failed_clk_enet_out:
> +		clk_disable_unprepare(fep->clk_ipg);
> +failed_clk_ipg:
>  		clk_disable_unprepare(fep->clk_ahb);
>  
>  	return ret;
> @@ -2864,14 +2847,10 @@ fec_enet_open(struct net_device *ndev)
>  	struct fec_enet_private *fep = netdev_priv(ndev);
>  	int ret;
>  
> -	ret = pm_runtime_get_sync(&fep->pdev->dev);
> -	if (IS_ERR_VALUE(ret))
> -		return ret;
> -
>  	pinctrl_pm_select_default_state(&fep->pdev->dev);
>  	ret = fec_enet_clk_enable(ndev, true);
>  	if (ret)
> -		goto clk_enable;
> +		return ret;
>  
>  	/* I should reset the ring buffers here, but I don't yet know
>  	 * a simple way to do that.
> @@ -2902,9 +2881,6 @@ err_enet_mii_probe:
>  	fec_enet_free_buffers(ndev);
>  err_enet_alloc:
>  	fec_enet_clk_enable(ndev, false);
> -clk_enable:
> -	pm_runtime_mark_last_busy(&fep->pdev->dev);
> -	pm_runtime_put_autosuspend(&fep->pdev->dev);
>  	pinctrl_pm_select_sleep_state(&fep->pdev->dev);
>  	return ret;
>  }
> @@ -2927,9 +2903,6 @@ fec_enet_close(struct net_device *ndev)
>  
>  	fec_enet_clk_enable(ndev, false);
>  	pinctrl_pm_select_sleep_state(&fep->pdev->dev);
> -	pm_runtime_mark_last_busy(&fep->pdev->dev);
> -	pm_runtime_put_autosuspend(&fep->pdev->dev);
> -
>  	fec_enet_free_buffers(ndev);
>  
>  	return 0;
> @@ -3415,10 +3388,6 @@ fec_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto failed_clk;
>  
> -	ret = clk_prepare_enable(fep->clk_ipg);
> -	if (ret)
> -		goto failed_clk_ipg;
> -
>  	fep->reg_phy = devm_regulator_get(&pdev->dev, "phy");
>  	if (!IS_ERR(fep->reg_phy)) {
>  		ret = regulator_enable(fep->reg_phy);
> @@ -3431,11 +3400,6 @@ fec_probe(struct platform_device *pdev)
>  		fep->reg_phy = NULL;
>  	}
>  
> -	pm_runtime_set_autosuspend_delay(&pdev->dev, FEC_MDIO_PM_TIMEOUT);
> -	pm_runtime_use_autosuspend(&pdev->dev);
> -	pm_runtime_set_active(&pdev->dev);
> -	pm_runtime_enable(&pdev->dev);
> -
>  	fec_reset_phy(pdev);
>  
>  	if (fep->bufdesc_ex)
> @@ -3483,10 +3447,6 @@ fec_probe(struct platform_device *pdev)
>  
>  	fep->rx_copybreak = COPYBREAK_DEFAULT;
>  	INIT_WORK(&fep->tx_timeout_work, fec_enet_timeout_work);
> -
> -	pm_runtime_mark_last_busy(&pdev->dev);
> -	pm_runtime_put_autosuspend(&pdev->dev);
> -
>  	return 0;
>  
>  failed_register:
> @@ -3498,8 +3458,6 @@ failed_init:
>  	if (fep->reg_phy)
>  		regulator_disable(fep->reg_phy);
>  failed_regulator:
> -	clk_disable_unprepare(fep->clk_ipg);
> -failed_clk_ipg:
>  	fec_enet_clk_enable(ndev, false);
>  failed_clk:
>  failed_phy:
> @@ -3609,28 +3567,7 @@ failed_clk:
>  	return ret;
>  }
>  
> -static int __maybe_unused fec_runtime_suspend(struct device *dev)
> -{
> -	struct net_device *ndev = dev_get_drvdata(dev);
> -	struct fec_enet_private *fep = netdev_priv(ndev);
> -
> -	clk_disable_unprepare(fep->clk_ipg);
> -
> -	return 0;
> -}
> -
> -static int __maybe_unused fec_runtime_resume(struct device *dev)
> -{
> -	struct net_device *ndev = dev_get_drvdata(dev);
> -	struct fec_enet_private *fep = netdev_priv(ndev);
> -
> -	return clk_prepare_enable(fep->clk_ipg);
> -}
> -
> -static const struct dev_pm_ops fec_pm_ops = {
> -	SET_SYSTEM_SLEEP_PM_OPS(fec_suspend, fec_resume)
> -	SET_RUNTIME_PM_OPS(fec_runtime_suspend, fec_runtime_resume, NULL)
> -};
> +static SIMPLE_DEV_PM_OPS(fec_pm_ops, fec_suspend, fec_resume);
>  
>  static struct platform_driver fec_driver = {
>  	.driver	= {

-- 
Pengutronix e.K.             | Lucas Stach                 |
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