Hi, On 4/5/2020 7:15 AM, Rob Herring wrote: > On Fri, Mar 27, 2020 at 03:11:56PM +0530, Tejas Joglekar wrote: >> This commit adds the documentation for consolidate-sgl, and >> snps,consolidate-sgl property. These when set enables the quirk for >> XHCI driver for consolidation of sg list into a temporary buffer when small >> buffer sizes are scattered over the sg list not making up to MPS or total >> transfer size within TRB cache size with Synopsys xHC. >> >> Signed-off-by: Tejas Joglekar <joglekar@xxxxxxxxxxxx> >> --- >> Documentation/devicetree/bindings/usb/dwc3.txt | 3 +++ >> Documentation/devicetree/bindings/usb/usb-xhci.txt | 3 +++ >> 2 files changed, 6 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt >> index 9946ff9ba735..292d1f7969e4 100644 >> --- a/Documentation/devicetree/bindings/usb/dwc3.txt >> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt >> @@ -104,6 +104,9 @@ Optional properties: >> this and tx-thr-num-pkt-prd to a valid, non-zero value >> 1-16 (DWC_usb31 programming guide section 1.2.3) to >> enable periodic ESS TX threshold. >> + - snps,consolidate-sgl: enable sg list consolidation - host mode only. Set to use >> + SG buffers of at least MPS size by consolidating smaller SG >> + buffers list into a single buffer. > > The preference is not to keep adding properties for every single quirk > or feature. These should be implied by specific compatibles. As Synopsys > knows what quirks/errata/features are in each version of IP, the > compatible strings should reflect those versions. (And yes, I'm sure > there's customer ECO fixes that aren't reflected in the version, but > that's why we have SoC specific compatibles too.) This is the only way > we can fix quirks in the OS without doing DT updates. For comparison, do > you want to have to update your PC BIOS so an OS can work-around issues? > Yes, I understand what you want to say here. But I think this compatible string does not work with the platform drivers with PCI based systems. So based on the vendor id and device id then I need to set the quirk required. @Felipe: What do you suggest for setting up quirk without the DT update for dwc3? > Rob > Thanks & Regards, Tejas Joglekar