On Mon, Apr 15, 2019 at 6:55 AM Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> wrote: > > pon., 15 kwi 2019 o 12:21 Sekhar Nori <nsekhar@xxxxxx> napisał(a): > > > > On 12/04/19 9:01 PM, Bartosz Golaszewski wrote: > > > pt., 12 kwi 2019 o 15:53 Sekhar Nori <nsekhar@xxxxxx> napisał(a): > > >> > > >> On 12/04/19 5:41 PM, Bartosz Golaszewski wrote: > > >>> pt., 12 kwi 2019 o 13:26 Sekhar Nori <nsekhar@xxxxxx> napisał(a): > > >>>> > > >>>> Hi Bartosz, > > >>>> > > >>>> On 08/04/19 1:29 PM, Bartosz Golaszewski wrote: > > >>>>> From: David Lechner <david@xxxxxxxxxxxxxx> > > >>>>> > > >>>>> This adds a cpu node and operating points to the common da850.dtsi file. > > >>>>> > > >>>>> Additionally, a regulator is added to the LEGO EV3 board along with > > >>>>> some board-specific CPU configuration. > > >>>>> > > >>>>> Regulators need to be hooked up on other boards to get them working. > > >>>>> > > >>>>> Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx> > > >>>>> Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> > > >>>> > > >>>> I remember you mentioning about some problems using OCHI and cpufreq > > >>>> together. Are those resolved now? CPU PLL on DA850 can affect other > > >>>> peripheral clock frequencies too. So enabling it should really be a > > >>>> per-board decision. > > >>>> > > >>> > > >>> The problems are still there. I've never been able to find the > > >>> culprit, but it also occurs on TI BSP in the same way (a couple > > >>> cpufreq transitions will make the controller unresponsive). > > >> > > >> Is that on LCDK as well? As I recall cpufreq was never enabled on LCDK > > >> in TI BSP. > > >> > > > > > > Yes, I just verified that the bug occurs on LCDK with patches from this series. > > > > > >> If the OHCI problem is present on LCDK, then there is a user visible > > >> regression on mainline after this patch. Lets enable cpufreq in LCDK > > >> only if all working peripherals keep working afterwards. > > >> > > > > > > The OHCI driver doesn't register any cpufreq transition notifier > > > callbacks. I can't really find anything in the datasheet, but I'm > > > wondering if we shouldn't do something similar to what the driver for > > > davinci i2c controller does. I'll try a couple things tomorrow. > > > > Even if OHCI issue is fixed, with a fixed regulator like on LCDK, I am > > not sure the benefits of just frequency scaling will be justifiable enough. > > > > Fixing the OHCI issue may help in other boards like da850-evm use it > > though. So that will be a good thing. > > > > How do you feel about keeping all OPPs disabled by default in da850.dtsi > > and enabling only the ones that make sense for a board in <board>.dts? > > > > Empty OPP table is illegal, so this does mean that every board must > > enable at least one OPP. > > > > I guess in that case we'd need to make 300 MHz the default for > da850-evm, but on da850-lcdk I'd go for 456 MHz (due to the regulator > being fixed anyway). Based on what I've seen of your V4 patch, I think it's fine to let the da850-evm run at 375. I am not sure why it would need to be default to 300. I agree that the cpu-supply is correctly referencing vdcdc3_reg, and it's currently setup to handle .95 to 1.35V, which I think is OK based on what I've seen and the OPP's look right from what I can tell. adam > > Bart
