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@freescale.com
Changes for v2: Corrected Signed-off footer
Applied to u-boot-mpc85xx/master, thanks.
York