Re: [PATCH 0/2] usb: dwc3: Add cache type configuration support for freescale layerscape

[Thinh Nguyen <Thinh.Nguyen@synopsys.com>]

Hi Frank,

On Wed, Jul 03, 2024, Frank Li wrote:
> There are several attempt to upstream this code in past year.
> 
> The first attempt:
> https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/20191121095356.GB7503@b29397-desktop/__;!!A4F2R9G_pg!cdNydVZ64br9EHG13lgP3lKWe5VuXQvvfvA1CzKJqhXZZB1H9vcJlwI1vj1EF3ynRFl2u8tD3lYqRvrJFSs2$ 
> 
> cache type is dwc core setting, not glue layer. So It'd better change in
> dwc core instead of glue layer code.

Why not glue layer?

> 
> The second attempt:
> https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/20240123170206.3702413-1-Frank.Li@nxp.com/*t__;Iw!!A4F2R9G_pg!cdNydVZ64br9EHG13lgP3lKWe5VuXQvvfvA1CzKJqhXZZB1H9vcJlwI1vj1EF3ynRFl2u8tD3lYqRh7SiHmM$ 
> 
> DT team think there are not variable for property 'snps,dat-wr-reqinfo'.
> And suggest use vendor compatible string.
> 
> This is third attempt:
> Compared with first attempt:
> - reduce compatible string to one 'fsl,ls-dwc3' because all setting are the
> same.
> - move update burst type code into dwc3_set_incr_burst_type(). and check
> compatible string 'fsl,ls-dwc3'.
> - Using bit field help macro.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> Ran Wang (2):
>       dt-bindings: usb: Add chip-specific compatible string 'fsl,ls-dwc3'
>       usb: dwc3: Set cache type to 'snoop' for freescale layerscape chip
> 
>  Documentation/devicetree/bindings/usb/snps,dwc3.yaml |  1 +
>  drivers/usb/dwc3/core.c                              | 12 ++++++++++++
>  drivers/usb/dwc3/core.h                              |  4 ++++
>  3 files changed, 17 insertions(+)
> ---
> base-commit: 0b58e108042b0ed28a71cd7edf5175999955b233
> change-id: 20240703-dwc-5be3e378ddbe
> 
> Best regards,
> ---
> Frank Li <Frank.Li@nxp.com>
> 

This may blow up the dwc3 core from various platforms and compatible
strings. This can be handled in the glue driver and create the software
property instead.

Radhey Shyam is working on this also. You can check his work here:

https://lore.kernel.org/linux-usb/1717657279-2631757-1-git-send-email-radhey.shyam.pandey@amd.com/

Thanks,
Thinh