Hi, On 05/12/2014 09:54 AM, Siarhei Siamashka wrote: > On Sun, 11 May 2014 22:47:03 +0200 > Hans de Goede <[email protected]> wrote: >
<snip> >> So what is your opinion no the 3th patch in this series which drops the >> DRAM clk on the cubieboard2 to 432 MHz ? > > It's all very complicated. We also had a report about some A20 device > not being able to run stable with dram clocked at 432MHz. Unless MBUS > was also synchronously clocked at 432MHz (using PLL5 instead of PLL6): > http://irclog.whitequark.org/linux-sunxi/2013-11-26#5690482 > To some extent this conflicts with the two assumptions from your > patch series ("432MHz is stable" and "fast MBUS is bad"). > > I would say that a bit more experiments are still needed. > > Also the whole patch series tries to address the issues, which are > only specific to Cubieboard2 and Cubietruck. My take on this is the > following. CubieTech is a commercial company selling these boards. > They are interested in having high specs listed on their website > (1GHz CPU, 480MHz DDR3). And they are also interested in having > their boards running stable at these clock speeds, because they > have to deal with the warranty and defective boards replacement. > CubieTech is also linux-sunxi community friendly with some of their > representatives available here (Huang Benn). So IMHO it's best if > we take the settings that CubieTech considers appropriate for their > hardware. If something is not quite right, then some corrections > may be applied. But then again, IMHO it's best to keep CubieTech > in the loop. The 432 MHz patch is cubie specific, the FAST_MBUS one is not though, we can fix Oliver's FAST_MBUS issue in another way I'm fine with using FAST_MBUS *everywhere*, my main problem with FAST_MBUS is that I want the define to go away and simply use the same settings everywhere, to make upstreaming all the u-boot-sunxi code easier. Regards, Hans -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
