Re: [PATCH] net: fec: Fix dual ethernet issue in VFxx

[Stefan Agner <stefan@agner.ch>]

Fwiw, this patch really touches many devices and disables the quirk for
some devices, but this is done by intent.

The quirk FEC_QUIRK_ENET_MAC was active for i.MX28, i.MX6Q, Vybrid
(mvf600-fec) and i.MX6SX. However, the new quirk is only enabled for
i.MX28. i.MX6Q doesn't need the quirk since there is one FEC instance
only anyway. Vybrid and i.MX6SX have a MDIO bus for each instance.

Acked-by: Stefan Agner <stefan@agner.ch>

On 2015-01-06 14:47, Bhuvanchandra DV wrote:
> On i.MX28, the MDIO bus is shared between the
> two RMII interfaces. However, in newer designs,
> such as Vybrid, this is not the case. This patch
> adds a quirk for the single MDIO case. This allows
> to use both FEC interfaces working independently
> on Vybird.
> 
> Signed-off-by: Bhuvanchandra DV <bhuvanchandra.dv@toradex.com>
> ---
>  drivers/net/ethernet/freescale/fec.h      |    3 +++
>  drivers/net/ethernet/freescale/fec_main.c |    7 ++++---
>  2 files changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/freescale/fec.h
> b/drivers/net/ethernet/freescale/fec.h
> index 469691a..c9515bc 100644
> --- a/drivers/net/ethernet/freescale/fec.h
> +++ b/drivers/net/ethernet/freescale/fec.h
> @@ -425,6 +425,9 @@ struct bufdesc_ex {
>   */
>  #define FEC_QUIRK_BUG_CAPTURE		(1 << 10)
>  
> +/* Controller has only one MDIO bus for interfacing external PHY's */
> +#define FEC_QUIRK_SINGLE_MDIO		(1 << 11)
> +
>  struct fec_enet_priv_tx_q {
>  	int index;
>  	unsigned char *tx_bounce[TX_RING_SIZE];
> diff --git a/drivers/net/ethernet/freescale/fec_main.c
> b/drivers/net/ethernet/freescale/fec_main.c
> index 5ebdf8d..22b7748 100644
> --- a/drivers/net/ethernet/freescale/fec_main.c
> +++ b/drivers/net/ethernet/freescale/fec_main.c
> @@ -91,7 +91,8 @@ static struct platform_device_id fec_devtype[] = {
>  		.driver_data = 0,
>  	}, {
>  		.name = "imx28-fec",
> -		.driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_SWAP_FRAME,
> +		.driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_SWAP_FRAME |
> +				FEC_QUIRK_SINGLE_MDIO,
>  	}, {
>  		.name = "imx6q-fec",
>  		.driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_GBIT |
> @@ -1952,7 +1953,7 @@ static int fec_enet_mii_init(struct platform_device *pdev)
>  	 * mdio interface in board design, and need to be configured by
>  	 * fec0 mii_bus.
>  	 */
> -	if ((fep->quirks & FEC_QUIRK_ENET_MAC) && fep->dev_id > 0) {
> +	if ((fep->quirks & FEC_QUIRK_SINGLE_MDIO) && fep->dev_id > 0) {
>  		/* fec1 uses fec0 mii_bus */
>  		if (mii_cnt && fec0_mii_bus) {
>  			fep->mii_bus = fec0_mii_bus;
> @@ -2015,7 +2016,7 @@ static int fec_enet_mii_init(struct platform_device *pdev)
>  	mii_cnt++;
>  
>  	/* save fec0 mii_bus */
> -	if (fep->quirks & FEC_QUIRK_ENET_MAC)
> +	if (fep->quirks & FEC_QUIRK_SINGLE_MDIO)
>  		fec0_mii_bus = fep->mii_bus;
>  
>  	return 0;