[U-Boot] [PATCH] net/phy/realtek: Disable interrupt on Realtek Ethernet PHY drivers

[Codrin Constantin Ciubotariu]

Hi,

Anyone has any comments on this? Please share your thoughts.

Thanks and best regards,
Codrin

> -----Original Message-----
> From: Codrin Ciubotariu [mailto:codrin.ciubotariu at freescale.com]
> Sent: Friday, February 13, 2015 2:48 PM
> To: u-boot at lists.denx.de
> Cc: Sun York-R58495; Ciubotariu Codrin Constantin-B43658
> Subject: [PATCH] net/phy/realtek: Disable interrupt on Realtek Ethernet PHY
> drivers
> 
> Some Realtek Ethernet PHYs, like RTL8211D(G/N) and RTL8211E(G), have interrupts
> enabled by default. If the interrupt is not treated later by the OS and the
> PHY's interrupt line is enabled and shared with other interrupts, the system
> will get an interrupt storm.
> This patch disables the interrupt for PHY devices that use one of the current
> Realtek Ethernet PHY drivers.
> Some of Realtek Ethernet PHYs, such as RTL8211B(L) have the interrupt masked. In
> this case, the functionality of the PHY should not be afected since this patch
> brings INER and INSR registers to their default values.
> 
> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu at freescale.com>
> Change-Id: Ic5e353da24f8fec335e446098ed863991a655554
> ---
>  drivers/net/phy/realtek.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c index
> a3ace68..ee97079 100644
> --- a/drivers/net/phy/realtek.c
> +++ b/drivers/net/phy/realtek.c
> @@ -3,7 +3,7 @@
>   *
>   * SPDX-License-Identifier:	GPL-2.0+
>   *
> - * Copyright 2010-2011 Freescale Semiconductor, Inc.
> + * Copyright 2010-2011, 2015 Freescale Semiconductor, Inc.
>   * author Andy Fleming
>   */
>  #include <config.h>
> @@ -21,12 +21,28 @@
>  #define MIIM_RTL8211x_PHYSTAT_SPDDONE  0x0800
>  #define MIIM_RTL8211x_PHYSTAT_LINK     0x0400
> 
> +/* RTL8211x PHY Interrupt Enable Register */
> +#define MIIM_RTL8211x_PHY_INER         0x12
> +#define MIIM_RTL8211x_PHY_INTR_ENA     0x9f01
> +#define MIIM_RTL8211x_PHY_INTR_DIS     0x0000
> +
> +/* RTL8211x PHY Interrupt Status Register */
> +#define MIIM_RTL8211x_PHY_INSR         0x13
> 
>  /* RealTek RTL8211x */
>  static int rtl8211x_config(struct phy_device *phydev)  {
>  	phy_write(phydev, MDIO_DEVAD_NONE, MII_BMCR, BMCR_RESET);
> 
> +	/* mask interrupt at init; if the interrupt is
> +	 * needed indeed, it should be explicitly enabled
> +	 */
> +	phy_write(phydev, MDIO_DEVAD_NONE, MIIM_RTL8211x_PHY_INER,
> +		  MIIM_RTL8211x_PHY_INTR_DIS);
> +
> +	/* read interrupt status just to clear it */
> +	phy_read(phydev, MDIO_DEVAD_NONE, MIIM_RTL8211x_PHY_INER);
> +
>  	genphy_config_aneg(phydev);
> 
>  	return 0;
> --
> 1.7.11.7