Hi, On Thu, Jan 8, 2015 at 6:21 AM, Iain Paton <ipat...@gmail.com> wrote: > On 24/12/14 15:29, wens Tsai wrote: > >> - AXP20x (PEK and docs) series, originally by Carlo, posted v8 >> - AXP20x regulator driver cleanup, finished and tested >> - AXP221 support, originally by Boris, finished and tested >> * Also enables WiFi on the Hummingbird A31 >> - sunxi (sun[457]i) cpufreq support, finished and testing (CB/CB2 tested) >> * Only added support for the boards I own. It's just a matter of adding >> the regulator nodes with the proper constraints > > Hi, > > I've been testing your patches with a20 olinuxino lime2 & a10 lime > > I notice your cpu opp data reduces the voltage down to 0.9v for the lowest > frequency, but all of the regulator nodes you added for cubieboard cubietruck > etc, have the lower limit set to 1v. Did you test 0.9v on anything?
Not before. The assumption was that we provide a generic set of OPPs. Board files then decide which ones are actually usable via regulator constraints. > The lime2 dts currently has 0.7v as the lower limit for dcdc2 and when it's > dropped to an opp with cpu core voltage set to 0.9v the board starts crashing > randomly very soon after. I just tested my cubieboard2, and it crashes as soon as the voltage is lowered to 0.9v by cpufrequtils. 0.9v is below the recommended voltage range for VDD-CPU, according to the datasheet. Running my board at 144 MHz / 1.0v seems fine though. > I'll post a patch shortly to raise the lime2 dcdc2 lower limit to 1v, but > I think it's probably worth collecting some more data on how many boards > will really be able to use that 0.9v setting. I can increase the voltage setting for 144 MHz to 1.0v in the dtsi. This brings out additional problems though. The clock driver doesn't support re-calculating the dividers ATM. So when the cpu clock is at 144 MHz, the ahb clocks run at 24 MHz, which IIRC is too slow for USB. Maybe I just remove it from the OPP set for the time being. > With the exception of altering the dcdc2 limits, I've not encountered any > other problems. Thanks for the feedback! ChenYu -- 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 linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
