have a queston on ddr2 clock speed on mcf54415 custom board.
What i actually so is :
- pll setup, i have
fref = 30Mhz,
refdiv = 0 (refdiv_divider = 1),
cpu_clock configured to 240Mhz
vco clock fixed at cpu_clock * 2,
bus_clock at cpu_clock / 2
- ddr2 (128MB) init / setup
- memtest, passes all 128MB
- finally, DDR2 clock checked by scope, i see a syn at abt 240Mhz.
Strangely, since i set that that ddr2 clock must come from VCO, with
/* use vco instead of cpu 2x clock for ddr clock */
move.l #MISCCR2, %a1
move.w #0xe01d, (%a1)
/* use cpu clock */
/* move.w #0xa01d, (%a1) */
should i expect 480Mhz as ddr2 clock and 240 only if i set ddr2 clock coming from cpu clock ?