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

Baruch Siach baruch at tkos.co.il
Wed Jan 19 10:14:06 PST 2022


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

>
> [1] https://lore.kernel.org/linux-usb/20220114044230.2677283-1-robert.hancock@calian.com/
>
> 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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   - baruch at tkos.co.il - tel: +972.52.368.4656, http://www.tkos.co.il -



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