From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Youn Subject: Re: [PATCH v2 2/4] usb: dwc2: Add binding for AHB burst Date: Thu, 17 Nov 2016 08:07:39 -0800 Message-ID: <88116f67-a8cd-74b0-a355-3365202d041e@synopsys.com> References: <7fa1c1c4d703c435d698cdf140c9d43163347f1d.1479339900.git.johnyoun@synopsys.com> <633e5a10-1ea0-48c7-a5b7-a5ff2625e759@i2se.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <633e5a10-1ea0-48c7-a5b7-a5ff2625e759-eS4NqCHxEME@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Stefan Wahren , John Youn , Felipe Balbi , "linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Rob Herring , Mark Rutland Cc: Christian Lamparter List-Id: devicetree@vger.kernel.org On 11/17/2016 7:35 AM, Stefan Wahren wrote: > Hi John, > > Am 17.11.2016 um 00:47 schrieb John Youn: >> Add the "snps,ahb-burst" binding and read it in. >> >> This property controls which burst type to perform on the AHB bus as a >> master in internal DMA mode. This overrides the legacy param value, >> which we need to keep around for now since several platforms use it. >> >> Some platforms may see better or worse performance based on this >> value. The HAPS platform is one example where all INCRx have worse >> performance than INCR. >> >> Other platforms (such as the Canyonlands board) report that the default >> value causes system hangs. >> >> Signed-off-by: John Youn >> Cc: Christian Lamparter >> --- >> Documentation/devicetree/bindings/usb/dwc2.txt | 2 + >> drivers/usb/dwc2/core.h | 9 +++++ >> drivers/usb/dwc2/params.c | 56 ++++++++++++++++++++++++++ >> 3 files changed, 67 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/usb/dwc2.txt b/Documentation/devicetree/bindings/usb/dwc2.txt >> index 6c7c2bce..9e7b4b4 100644 >> --- a/Documentation/devicetree/bindings/usb/dwc2.txt >> +++ b/Documentation/devicetree/bindings/usb/dwc2.txt > > according to Documentation/devicetree/bindings/submitting-patches.txt > this change should be a separate patch. Ok > >> @@ -26,6 +26,8 @@ Optional properties: >> Refer to phy/phy-bindings.txt for generic phy consumer properties >> - dr_mode: shall be one of "host", "peripheral" and "otg" >> Refer to usb/generic.txt >> +- snps,ahb-burst: specifies the ahb burst length. Valid arguments are: >> + "SINGLE", "INCR", "INCR4", "INCR8", "INCR16". Defaults to "INCR4". > > This doesn't apply in case of the bcm2835. I would prefer this option is > ignored in that case with a dev_warn("snps,ahb-burst is not supported on > this platform"). Sure I'll add this. Regards, John -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html