Am Donnerstag, 15. Mai 2014, 11:18:44 schrieb Doug Anderson: > Thomas, > > On Tue, May 13, 2014 at 6:11 PM, Thomas Abraham <ta.omasab@xxxxxxxxx> wrote: > > From: Thomas Abraham <thomas.ab@xxxxxxxxxxx> > > +static int exynos4210_armclk_pre_rate_change(struct clk_notifier_data > > *ndata, + struct exynos_cpuclk *armclk, void > > __iomem *base) +{ > > + struct exynos4210_armclk_data *armclk_data = armclk->data; > > + unsigned long alt_prate = clk_get_rate(armclk->alt_parent); > > + unsigned long alt_div, div0, div1, tdiv0, mux_reg; > > + unsigned long cur_armclk_rate, timeout; > > + unsigned long flags; > > + > > + /* find out the divider values to use for clock data */ > > + while (armclk_data->prate != ndata->new_rate) { > > + if (armclk_data->prate == 0) > > + return -EINVAL; > > + armclk_data++; > > + } > > + > > + div0 = armclk_data->div0; > > + div1 = armclk_data->div1; > > + if (readl(base + SRC_CPU) & EXYNOS4210_MUX_HPM_MASK) { > > + div1 = readl(base + DIV_CPU1) & EXYNOS4210_DIV1_HPM_MASK; > > + div1 |= ((armclk_data->div1) & ~EXYNOS4210_DIV1_HPM_MASK); > > + } > > + > > + /* > > + * if the new and old parent clock speed is less than the clock > > speed + * of the alternate parent, then it should be ensured that > > at no point + * the armclk speed is more than the old_prate until > > the dividers are + * set. > > + */ > > + tdiv0 = readl(base + DIV_CPU0); > > + cur_armclk_rate = ndata->old_rate / EXYNOS4210_ARM_DIV1(tdiv0) / > > + EXYNOS4210_ARM_DIV2(tdiv0); > > + if (alt_prate > cur_armclk_rate) { > > + alt_div = _calc_div(alt_prate, cur_armclk_rate); > > + _exynos4210_set_armclk_div(base, alt_div); > > + div0 |= alt_div; > > Don't you need to up the voltage here, too? ...I haven't reviewed > this whole patch (so perhaps it's elsewhere in the patch or in the > series), but I stumbled upon this while trying to solve a different > problem and figured I'd check... setting the voltage should be done by the cpufreq driver like cpufreq-cpu0 - whose usage this series intents to allow. As I've hijacked Thomas' concept for my current rockchip clock work, I've already seen this working nicely :-) . Heiko -- 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