From: Badola Nikhil <nikhil.badola@freescale.com>
To: Mark Rutland <mark.rutland@arm.com>
CC: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "balbi@ti.com" <balbi@ti.com>
Subject: RE: [PATCH 1/3] Documentation: dt: dwc3: Add snps,configure-fladj
 property
Thread-Topic: [PATCH 1/3] Documentation: dt: dwc3: Add snps,configure-fladj
 property
Thread-Index: AQHQxSwX6I6RwEFjPk+QSaNMsW8cdJ3o0V+AgAAByoCAAA86gIAAAD+Q
Date: Thu, 23 Jul 2015 11:07:09 +0000
Message-ID: <SN1PR0301MB162957FD79F00321A42243F3F3820@SN1PR0301MB1629.namprd03.prod.outlook.com>
References: <1437646161-1764-1-git-send-email-nikhil.badola@freescale.com>
 <20150723095635.GA12330@leverpostej>
 <SN1PR0301MB1629C9F2083C8C4F5CE8CE4EF3820@SN1PR0301MB1629.namprd03.prod.outlook.com>
 <20150723105729.GB12330@leverpostej>
In-Reply-To: <20150723105729.GB12330@leverpostej>
Accept-Language: en-US
Content-Language: en-US
sn1pr0301mb1632: X-MS-Exchange-Organization-RulesExecuted
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 8BIT
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-originalarrivaltime: 23 Jul 2015 11:07:09.7113
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 710a03f5-10f6-4d38-9ff4-a80b81da590d
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN1PR0301MB1632
X-Microsoft-Exchange-Diagnostics: 1;SN1PR0301MB1616;2:pYTY990Lfx8IBLrFAYcosgiQiIWDOvFhBUPHd1n3KXC650+FN3Nkoqdr5O87tkgr;3:DivUWixw9sYJB0MY54KD/VKue6PUbP6jnmeUoJ2KpEmV7lX1h+YeZgISVGDVJrz4Imsn8s4t44ODJc3u4jPQEx8sgwNTOAJXi5ZiNDmd4KQF4Pkc00ia7sS+3KqBJrj6ev+DwlDgRynkPcg9zb/ncg==;25:uDMGwsTRVTzXm00pFIXPmrSDndzCpBZwYlGrU/zsy1AQgve1vA5FeJebgMTDaOWca5o8gbEVKcHoyAGSTDldzjV+cazHJx3qmrQMbLQmN4J2stIIgeR0lts3kugcPhtJV9Wtrad8c8Pwps++PEK1g33SLKHa/SeRHTYIVKq4B0btVNK9xl5gdPyaz0VqR3FMnu4KOXQ9zSwFNuAs5ahmlZV7fkbvLwOYWvlE7/Vkgt4MxRTL2mxddWAwGReVG2dueU7tjvIR8An49MRODrc7mw==
X-Microsoft-Exchange-Diagnostics: 1;SN1PR0301MB1616;20: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;23:DWLc1Ib+sknz9ZFUWZWiFyo+G2w+jxihKwAt0MN7K6gS2cdR12J0sO9tELmByq37JVUVkRZSTOqZYAdAqQklPCFJYtEn9G9d+IWcnvXvYVIF8i+Dc5ua6GqG5WfvMiqGNzDeIvGtfGKcl+UE+UU2QFTqDNG8zi+QkIJA60EMb3thj2z+2e42m5J4IFYlfmpsY/vmgdHC2r6e64hMs6/bQh7+fBopHER8umxQQZbzSWgI5DvY/6Z+9NycsqZcI0oW
SN1PR0301MB1616: X-MS-Exchange-Organization-RulesExecuted
X-OriginatorOrg: freescale.com
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 3225
Lines: 83

> -----Original Message-----
> From: Mark Rutland [mailto:mark.rutland@arm.com]
> Sent: Thursday, July 23, 2015 4:27 PM
> To: Badola Nikhil-B46172
> Cc: linux-kernel@vger.kernel.org; devicetree@vger.kernel.org; balbi@ti.com
> Subject: Re: [PATCH 1/3] Documentation: dt: dwc3: Add snps,configure-fladj
> property
> 
> On Thu, Jul 23, 2015 at 11:52:19AM +0100, Badola Nikhil wrote:
> > > -----Original Message-----
> > > From: Mark Rutland [mailto:mark.rutland@arm.com]
> > > Sent: Thursday, July 23, 2015 3:27 PM
> > > To: Badola Nikhil-B46172
> > > Cc: linux-kernel@vger.kernel.org; devicetree@vger.kernel.org;
> > > balbi@ti.com
> > > Subject: Re: [PATCH 1/3] Documentation: dt: dwc3: Add
> > > snps,configure-fladj property
> > >
> > > On Thu, Jul 23, 2015 at 11:09:21AM +0100, Nikhil Badola wrote:
> > > > Add property snps,configure-fladj for enabling post silicon frame
> > > > length adjustment
> > > >
> > > > Signed-off-by: Nikhil Badola <nikhil.badola@freescale.com>
> > > > ---
> > > >  Documentation/devicetree/bindings/usb/dwc3.txt | 1 +
> > > >  1 file changed, 1 insertion(+)
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt
> > > > b/Documentation/devicetree/bindings/usb/dwc3.txt
> > > > index 0815eac..90c3972 100644
> > > > --- a/Documentation/devicetree/bindings/usb/dwc3.txt
> > > > +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
> > > > @@ -40,6 +40,7 @@ Optional properties:
> > > >   - snps,hird-threshold: HIRD threshold
> > > >   - snps,hsphy_interface: High-Speed PHY interface selection
> > > > between
> > > "utmi" for
> > > >     UTMI+ and "ulpi" for ULPI when the DWC_USB3_HSPHY_INTERFACE
> > > > has
> > > value 3.
> > > > + - snps,configure-fladj: enables post-silicon frame length
> > > > + adjustment
> > >
> > > Could you elaborate on what this means and why you think it's
> necessary?
> >
> > This property enables the use of GFLADJ_30MHZ field value of gfladj
> > register for frame length adjustment instead of considering from the
> sideband input signal fladj_30mhz_reg from SOC.
> > This is required when signal fladj_30mhz_reg is connected to a wrong
> > value or is not valid as in our case, hence post-silicon.
> 
> Ok, so this is basically an override for the GFLADJ_30MHZ field of the gfladj
> register when there was a problem at integration time.
>

That's right. 
 
> > However this field can be used to adjust any offset ranging from 00h
> > to 3Fh, from the clock source generating SOF(start of frame) packets.
> > Thus, this property can be added to device tree with appropriate
> adjustment value.
> 
> It takes a value? The description above makes it sound like a boolean
> property.
> 
> I'd expect a description more like:
> 
> - snps,fladj-override: Value for GFLADJ_30MHZ when the fladj_30mhz_reg
>   signal is invalid or incorrect.
> 
> Which makes it clear what the value is and when it should be set.

Agreed. Will change and send a new version of the patch-set.

> 
> Thanks,
> Mark.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/