On Fri, Jul 4, 2014 at 6:14 AM, Robert Jarzmik <robert.jarzmik@xxxxxxx> wrote: > Haojian Zhuang <haojian.zhuang@xxxxxxxxx> writes: > >>> Haojian, are you ok with that ? And BTW, does a combined kernel for PXA >>> platforms even exists (mixing pxa3xx and pxa2xx for example) ? >>> >> >> It's acceptable to me that different silicons are queued in different stages. >> I only request that it won't break the compiler building & bootup. > OK. > >> >> But I think that the pxa clock driver may be shared among all PXA silicons >> except for the clock table. What's your opinion? > I don't think so because of the core clocks. > These ones are specific to each pxa, and so their computation is : > - pxa25x plays with CCCR and specific L, M and N2 multiplication tables > - pxa27x plays with CCCR and specific L, M and N2 multiplication tables > - pxa3xx plays with ASCR, MEMCLKCFG, and AC97 div > > I don't see very well how a clock table could describe that. Do you have > something specific in mind ? > As I remember, those registers bits are encoded. So we can define a clock mux that connected to those fixed clock dividers. Then the clock gate is the child of the clock mux. In DTS file, peripheral device node could specify a clock rate. In peripheral device driver, it could also change the clock rate by clk_set_rate(). >>>> Also (for my understanding) when you say that you plan to do >>>> pxa25x and pxa3xx next, does that include pxa26x and pxa93x? >>> I don't have the Technical Reference Manuals for these ones so the answer is >>> no. And Google wasn't a great friend at providing them. >>> >> >> Converting them into new clock driver may not rely on the reference manual. > Actually I went through the code and : > - pxa26x is only a superset of pxa25x with one more clock : pxa26x-gpio > - pxa93x is the same clock set as pxa3xx, right ? > So if I convert pxa25x, pxa27x and pxa3xx I'll cover everything, right ? > >>>> I assume it does as they are apparently minor revisions of the >>>> former, but it's not completely clear from your description. >>> My description doesn't mention them, as I have no information about them, nor >>> any hardware to test on. >>> >> >> We can request others to help testing in the mailing list. > That's exactly what will enable pxa25x and pxa3xx. I have them converted in my > tree, but I don't want to mix these patches in as I can't test them, and testing > brings in bigger delays. Delay shouldn't be the block issue. Regards Haojian -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
