`Sorry I was away for some time. On 08/08, Hoan Tran wrote:> On Wed, Jul 20, 2016 at 11:36 AM, Hoan Tran <hotran@apm.com> wrote:> > On Fri, Jul 1, 2016 at 5:09 PM, Hoan Tran <hotran@apm.com> wrote:> >>> >> Hi Stephen,> >>> >> On Fri, Jul 1, 2016 at 11:38 AM, Stephen Boyd <sboyd@codeaurora.org> wrote:> >> > Sorry I replied offlist before. Pressed the wrong key.> >> >> >> > On 06/30, Hoan Tran wrote:> >> >> On Thu, Jun 30, 2016 at 1:23 PM, Stephen Boyd <sboyd@codeaurora.org> wrote:> >> >> >> >> >> > How is this different from clk-fractional-divider.c?> >> >> >> >> >>> >> >> This is a driver which clock output is multiplied with a fixed fractional> >> >> scale (denominator).> >> >> A field inside a register is used to configure the multiplier.> >> >>> >> >> Example: With fractional scale is 1/8.> >> >> Freq_out = Freq_parent * multiplier * (1/8)> >> >>> >> >> For fractional-divider, there are 2 fields of a register are used which> >> >>  - A field for numerator> >> >>  - A field for denominator> >> >> Freq_out = Freq_parent * numerator / denominator> >> >>> >> >> >> > Ok so the difference is that the denominator is a fixed value?> >>> >> The major difference is a fixed denominator.> >> Another difference is:> >> In case CLK_FRACTIONAL_SCALE_INVERTED=1, the freq_out is calculated as below> >>> >> Freq_out = Freq_parent * (fixed_denominator - multiplier) / fixed_denominator.> >>> >> > Perhaps that can be modeled as a clk-multiplier that is used as> >> > the only parent of a fixed divider?> >>> >> Because of CLK_FRACTIONAL_SCALE_INVERTED flag, I don't know how to> >> model as a clk-multiplier. And how to pass the fixed denominator into> >> a clk-multiplier.Would it be possible to add a flag to clk-multiplier to handlethe inverted case? I haven't seen anyone else with hardware likethat though, so perhaps the implementation should just go intothe vendor specific clk driver instead of being writtenas a "basic clk type".-- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,a Linux Foundation Collaborative Project`