[U-Boot] [PATCH][v2] driver/net/fm/memac_phy: Initialize mdio_clock for SoCs wih FMANv3

York Sun yorksun at freescale.com
Thu Apr 24 00:02:29 CEST 2014


On 04/07/2014 10:25 PM, Priyanka Jain wrote:
> MDIO clock needs to be initialized in u-boot code for SoCs
> having FMAN-v3(v3H or v3L) controller due to below reasons
> 
> -On SoCs that have FMAN-v3H  like B4860, default value of
> MDIO_CLK_DIV bits in mdio_stat(mdio_cfg) register generates
> mdio clock too high (much higher than 2.5MHz), violating the
> IEEE specs.
> -On SOCs that have FMAN-v3L like T1040, default value of
> MDIO_CLK_DIV bits is zero, so MDIO clock is disabled.
> 
> So, for proper functioninig of MDIO, MDIO_CLK_DIV bits needs to
> be properly initialized.
> Also this type of initialization is generally done in
> PBI(pre-bootloader) phase using rcw.But for chips like T1040
> which support deep-sleep, such type of initialization cannot be
> done in PBI phase due to the limitation that during deep-sleep
> resume, FMAN (MDIO) registers are not accessible in PBI phase.
> So, mdio clock initailization must be done as part of u-boot.
> 
> This initialization code is implemented in memac_phy.c which
> gets compiled only for SoCs having FMANv3, so no extra compilation
> flag is required.
> 
> Signed-off-by: Priyanka Jain <Priyanka.Jain at freescale.com>
> ---
>  Changes for v2: Corrected Signed-off footer
> 

Applied to u-boot-mpc85xx/master, thanks.

York



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