Messages in this thread | | | From | Andy Tang <> | Subject | RE: [PATCH] cpufreq: qoriq: enhance bus frequency calculation | Date | Fri, 10 Mar 2017 10:12:44 +0000 |
| |
Hi Viresh,
> -----Original Message----- > From: Viresh Kumar [mailto:viresh.kumar@linaro.org] > Sent: Friday, March 10, 2017 6:05 PM > To: Andy Tang > Cc: rjw@rjwysocki.net; linux-pm@vger.kernel.org; linux- > kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org > Subject: Re: [PATCH] cpufreq: qoriq: enhance bus frequency calculation > > On 10-03-17, 01:44, Andy Tang wrote: > > > Will this always work? If yes, then what about dropping the code > > > parsing DT completely ? That is, just rely on clk_get_rate() in all cases. > > > > > We put all the clock tree configuration in driver, not in dts. > > cg-pll0-div1 is hardcoded in driver since we don't depend on dts. > > We kind of don't have other choices but use the hardcode clock name > > here too. > > Looks like you misread my comment. Let me try again. Will it be fine to write > get_bus_freq() this way? > > static u32 get_bus_freq(void) > { > struct clk *pltclk; > > /* get platform freq by its clock name */ > pltclk = clk_get(NULL, "cg-pll0-div1"); > if (IS_ERR(pltclk)) { > pr_err("%s: can't get bus frequency %ld\n", > __func__, PTR_ERR(pltclk)); > return PTR_ERR(pltclk); > } > > return clk_get_rate(pltclk); > } > Yes, we can. But for some legacy powerpc-based socs, this may not work. powerpc-base socs are still using legacy clock driver. For compatibility sake, we better be compatible with old ones. It would break any compatibility this way.
Regards, Yuantian
> -- > viresh
| |