• Rasmus Villemoes's avatar
    mmc: fsl_esdhc: actually enable cache snooping on mpc830x · ede28228
    Rasmus Villemoes authored and Peng Fan's avatar Peng Fan committed
    
    
    The reference manuals for MPC8308 and MPC8309 both say that the
    esdhcctl aka DMA Control Register "is implemented as SDHCCR" in the
    System configuration registers. Unfortunately, that doesn't mean that
    the registers are just mirrors of each other - any write to esdhcctl
    is simply ignored. So to actually enable cache snooping, we
    unfortunately have to add a little ifdeffery.
    
    There is, naturally, no description of the bit fields of esdhcctl in
    the MPC8309 manual, but comparing the description of esdhcctl from the
    LS1021A reference manual to the description of the sdhccr in MPC8309,
    one also finds that the fields are bit-reversed, so the bit to set is
    0x02000000 rather than 0x00000040 - this is also what board_mmc_init()
    uses in the two gdsys/mpc8308/ boards.
    Signed-off-by: default avatarRasmus Villemoes <rasmus.villemoes@prevas.dk>
    Reviewed-by: default avatarYangbo Lu <yangbo.lu@nxp.com>
    ede28228
fsl_esdhc.c 22.9 KB