• Priyanka Jain's avatar
    powerpc/mpc85xx: Add support for single source clocking · b135991a
    Priyanka Jain authored
    Single-source clocking is new feature introduced in T1040.
    In this mode, a single differential clock is supplied to the
    DIFF_SYSCLK_P/N inputs to the processor, which in turn is
    used to supply clocks to the sysclock, ddrclock and usbclock.
    So, both ddrclock and syclock are driven by same differential
    sysclock in single-source clocking mode whereas in normal clocking
    mode, generally separate DDRCLK and SYSCLK pins provides
    reference clock for sysclock and ddrclock
    DDR_REFCLK_SEL rcw bit is used to determine DDR clock source
    -If DDR_REFCLK_SEL rcw bit is 0, then DDR PLLs are driven in
     normal clocking mode by DDR_Reference clock
    -If DDR_REFCLK_SEL rcw bit is 1, then DDR PLLs are driven in
     single source clocking mode by DIFF_SYSCLK
    Add code to determine ddrclock based on DDR_REFCLK_SEL rcw bit.
    Signed-off-by: default avatarPoonam Aggrwal <poonam.aggrwal@freescale.com>
    Signed-off-by: default avatarPriyanka Jain <Priyanka.Jain@freescale.com>
config_mpc85xx.h 28.1 KB