Re: [PATCH v2 0/7] usb: dwc3: Calculate REFCLKPER et. al. from reference clock

[Kathiravan T]

On 2022-01-19 23:44, Baruch Siach wrote:
> Hi Sean,
>
> On Tue, Jan 18 2022, Sean Anderson wrote:
> > This is a rework of patches 3-5 of [1]. It attempts to correctly 
> > program
> > REFCLKPER and REFCLK_FLADJ based on the reference clock frequency. 
> > Since
> > we no longer need a special property duplicating this configuration,
> > snps,ref-clock-period-ns is deprecated.
> >
> > Please test this! Patches 3/4 in this series have the effect of
> > programming REFCLKPER and REFCLK_FLADJ on boards which already 
> > configure
> > the "ref" clock. I have build tested, but not much else.
>
> Tested here on IPQ6010 based system. USB still works. But the with 
> "ref"
> clock at 24MHz, period is calculated as 0x29. Previous
> snps,ref-clock-period-ns value used to be 0x32.
>
> Is that expected?
>
> Thanks,
> baruch


Hi Baruch,

Yes, it is 0x29 for IPQ60xx based SoCs. In downstream it was wrongly 
mentioned as 0x32, which was corrected recently.

Thanks,
Kathiravan T.

> > [1] 
> > https://lore.kernel.org/linux-usb/20220114044230.2677283-1-robert.hancock@xxxxxxxxxx/
> >
> > Changes in v2:
> > - Document clock members
> > - Also program GFLADJ.240MHZDECR
> > - Don't program GFLADJ if the version is < 2.50a
> > - Add snps,ref-clock-frequency-hz property for ACPI
> >
> > Sean Anderson (7):
> >   dt-bindings: usb: dwc3: Deprecate snps,ref-clock-period-ns
> >   usb: dwc3: Get clocks individually
> >   usb: dwc3: Calculate REFCLKPER based on reference clock
> >   usb: dwc3: Program GFLADJ
> >   usb: dwc3: Add snps,ref-clock-frequency-hz property for ACPI
> >   arm64: dts: zynqmp: Move USB clocks to dwc3 node
> >   arm64: dts: ipq6018: Use reference clock to set dwc3 period
> >
> >  .../devicetree/bindings/usb/snps,dwc3.yaml    |   7 +-
> >  arch/arm64/boot/dts/qcom/ipq6018.dtsi         |   3 +-
> >  .../arm64/boot/dts/xilinx/zynqmp-clk-ccf.dtsi |   4 +-
> >  arch/arm64/boot/dts/xilinx/zynqmp.dtsi        |   4 +-
> >  drivers/usb/dwc3/core.c                       | 112 
> > +++++++++++++++---
> >  drivers/usb/dwc3/core.h                       |  17 ++-
> >  6 files changed, 120 insertions(+), 27 deletions(-)

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