thelightguy wrote:Cool! I wasn't sure if the RAM speed had to be an integer multiple of anything like the various GPU timings.
No. ARM, SDRAM and GPU each have their own PLLs can can be unrelated frequencies.
The GPU core, h264, v3d and isp share a PLL, so need to have related frequencies.
Looking at the code, the PLL will be set to:
pll_freq = core_freq * 2^n, for smallest n satisfying pll_freq > 600MHz.
GPU core, h264, v3d and isp should all be integer divisors of PLL freq.
So if core_freq=480, then pll_freq=960. That would allow a v3d_freq of 320 with an integer divider.