From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1h3F7n-0005Xv-KG for barebox@lists.infradead.org; Mon, 11 Mar 2019 07:13:29 +0000 Date: Mon, 11 Mar 2019 08:13:25 +0100 From: Sascha Hauer Message-ID: <20190311071325.2q3x2x3ntupsp4td@pengutronix.de> References: <20190307074813.19664-1-andrew.smirnov@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190307074813.19664-1-andrew.smirnov@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH] usb: dwc3: Toggle GCTL.CORESOFTRESET as a first step To: Andrey Smirnov Cc: barebox@lists.infradead.org On Wed, Mar 06, 2019 at 11:48:13PM -0800, Andrey Smirnov wrote: > Toggle GCTL.CORESOFTRESET before trying to access any of the block's > registers. Without this additional step, first read of DWC3_GHWPARAMS* > that follows results in assertion of GSTS.CSRTIMEOUT and IP block > stuck in a non-functional state. > > Note that all above has only been observed on i.MX8MQ (ZII Zest board) > for USB1 controller. USB2 doesn't seem to be affected by this. > > Signed-off-by: Andrey Smirnov > --- > drivers/usb/dwc3/core.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index 2e7031a34..1fc24a441 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -663,6 +663,21 @@ static void dwc3_check_params(struct dwc3 *dwc) > } > } > > +static void dwc3_coresoft_reset(struct dwc3 *dwc) > +{ > + u32 reg; > + > + reg = dwc3_readl(dwc->regs, DWC3_GCTL); > + reg |= DWC3_GCTL_CORESOFTRESET; > + dwc3_writel(dwc->regs, DWC3_GCTL, reg); > + > + mdelay(100); 100ms is quite long. Isn't a shorter delay enough? Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox