Hi Yadwinder, > Hi Tomasz, > > >> On Wed, Sep 25, 2013 at 4:52 PM, Lukasz Majewski > >> <l.majewski@xxxxxxxxxxx> wrote: > >> > In the exynos4x12_set_apll() function, the APLL frequency is set > >> > with direct register manipulation. > >> > > >> > Such approach is not allowed in the common clock framework. The > >> > frequency is changed, but the corresponding clock value is not > >> > updated. This causes wrong frequency read from cpufreq's > >> > cpuinfo_cur_freq sysfs attribute. > >> > > >> > >> This patch looks incomplete, leaving the driver in untidy state, > >> perhaps its doesn't fix the above stated problem completely. what > >> about if (!exynos4x12_pms_change(old_index, new_index)) becomes > >> true? > >> > >> IMHO, this driver needs lot more work in addition to this patch to > >> cleanly and completely move the cpufreq driver to common clock > >> framework. > > > > I agree that the other case needs to be handled as well. Basically > > the whole conditional block dependent on exynos4x12_pms_change() > > can be safely dropped, because this condition is already handled in > > PLL driver. > > > > Exactly! After more corner case testing, I admit that corner cases with PLL s parameter change are still broken (e.g. 1400000 -> 700000). I will prepare v2 for it. If I manage I will push it into -rc. If not those changes will be included to exynos cpufreq rework. Thanks guys for a thorough review. > > > Lukasz is already working on further rework of this driver to clean > > it up from legacy code, but this will have to wait for 3.13, as > > 3.12 is already in rc stage and only fixes can be accepted for it. > > > >> For fixing this issue urgently, setting CLK_GET_RATE_NOCACHE for > >> apll in clk driver can also be quicker fix. > > > > Unfortunately this is not how this flag works. It only makes > > clk_get_rate() call ->recalc_rate() operation of the clock instead > > of instantly returning cached rate - it doesn't seem to work > > recursively. > > > > hmm.. yes it can't help in our case as it recursively walks only the > subtree of clk but in our case we are changing rate of parent. > > Regards, > Yadwinder -- Best regards, Lukasz Majewski Samsung R&D Institute Poland (SRPOL) | Linux Platform Group -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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