From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arun Ramamurthy Date: Mon, 02 Mar 2015 19:09:51 +0000 Subject: Re: [PATCH] video: ARM CLCD: Added support for FBIOPAN_DISPLAY and virtual y resolution Message-Id: <54F4B57F.3030306@broadcom.com> List-Id: References: <1424898082-1522-1-git-send-email-arun.ramamurthy@broadcom.com> <1424898082-1522-2-git-send-email-arun.ramamurthy@broadcom.com> <1425312509.3092.7.camel@arm.com> <20150302161122.GP8656@n2100.arm.linux.org.uk> In-Reply-To: <20150302161122.GP8656@n2100.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Russell King - ARM Linux , Pawel Moll Cc: Rob Herring , Mark Rutland , Ian Campbell , Kumar Gala , Jean-Christophe Plagniol-Villard , Tomi Valkeinen , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-fbdev@vger.kernel.org" , Dmitry Torokhov , Anatol Pomazau , Jonathan Richardson , Scott Branden , Ray Jui , "bcm-kernel-feedback-list@broadcom.com" On 15-03-02 08:11 AM, Russell King - ARM Linux wrote: > On Mon, Mar 02, 2015 at 04:08:29PM +0000, Pawel Moll wrote: >> I'm not sure about this... The word "virtual" never works well with >> device tree nodes defined as "hardware description". >> >> I understand what you're doing, but adding this property to the display >> controller's node doesn't sound right. How does this describe hardware? >> If anywhere, it's more like a job for the panel node? > I see what you are saying Pawel, I can follow Russell's recommendation of adding a RAM size node called max-memory-available or something similar > A better description (and implementation) would be to describe the size > of the RAM available for video purposes. The driver can then use the > requested virtual X resolution to limit (and/or compute) the virtual Y > resolution to allow Y panning/wrapping of the display. > In this scenario, where would I specify the virtual X resolution? I am assuming it would be in the panel-timing node as Pawel suggested? > This would match some hardware where the video RAM is indeed a separate > physical set of RAM (such as the IM-PD/1). > From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arun Ramamurthy Subject: Re: [PATCH] video: ARM CLCD: Added support for FBIOPAN_DISPLAY and virtual y resolution Date: Mon, 2 Mar 2015 11:09:51 -0800 Message-ID: <54F4B57F.3030306@broadcom.com> References: <1424898082-1522-1-git-send-email-arun.ramamurthy@broadcom.com> <1424898082-1522-2-git-send-email-arun.ramamurthy@broadcom.com> <1425312509.3092.7.camel@arm.com> <20150302161122.GP8656@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150302161122.GP8656@n2100.arm.linux.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: Russell King - ARM Linux , Pawel Moll Cc: Rob Herring , Mark Rutland , Ian Campbell , Kumar Gala , Jean-Christophe Plagniol-Villard , Tomi Valkeinen , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-fbdev@vger.kernel.org" , Dmitry Torokhov , Anatol Pomazau , Jonathan Richardson , Scott Branden , Ray Jui , "bcm-kernel-feedback-list@broadcom.com" List-Id: devicetree@vger.kernel.org On 15-03-02 08:11 AM, Russell King - ARM Linux wrote: > On Mon, Mar 02, 2015 at 04:08:29PM +0000, Pawel Moll wrote: >> I'm not sure about this... The word "virtual" never works well with >> device tree nodes defined as "hardware description". >> >> I understand what you're doing, but adding this property to the display >> controller's node doesn't sound right. How does this describe hardware? >> If anywhere, it's more like a job for the panel node? > I see what you are saying Pawel, I can follow Russell's recommendation of adding a RAM size node called max-memory-available or something similar > A better description (and implementation) would be to describe the size > of the RAM available for video purposes. The driver can then use the > requested virtual X resolution to limit (and/or compute) the virtual Y > resolution to allow Y panning/wrapping of the display. > In this scenario, where would I specify the virtual X resolution? I am assuming it would be in the panel-timing node as Pawel suggested? > This would match some hardware where the video RAM is indeed a separate > physical set of RAM (such as the IM-PD/1). >