On 03/14/2014 07:32 AM, Shawn Guo wrote: > On Thu, Mar 13, 2014 at 07:44:24PM +0800, Jisheng Zhang wrote: >>> On 13 March 2014 16:25, Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote: >>>> On 13 March 2014 16:18, Jisheng Zhang <jszhang@xxxxxxxxxxx> wrote: >>>>> Hi all, >>>>> >>>>> cpufreq-cpu0 is suitable for Marvell Berlin SoC. But there's one issue >>>>> to address. The opp is different between chips even on the same step >>>>> SoC, BG2Q for example. we can calculate the OPP table from the value of >>>>> one OTP register. We have two solutions: >>>>> >>>>> 1. bootloader reads OTP register and calculate the OPP table then change >>>>> dtb danamically >>>>> >>>>> 2. supply one driver in mach-berlin to initialize the OPP table; and >>>>> modify cpufreq-cpu0 to allow platform supply OPP table, fall back to >>>>> of_init_opp_table() if there's no OPP table. >>>>> >>>>> Which solution is better? >>>> >>>> I think we can go ahead with second option here. We can just check if opp >>>> tables are already initialized or not. In case they are, don't probe from >>>> dt.. >>>> >>>> But lets see with others have to say here.. > > Yea, we had gone for the second option on imx6q-cpufreq driver with > commit 20b7cbe (cpufreq: imx6q: add of_init_opp_table). There might be a better alternative here given the scope of potential reuse cross SoCs - a generic opp modifier logic which'd work for all of us. I will let Dave Gerlach post his series to give an idea. -- Regards, Nishanth Menon -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
