Re: [PATCH v5 1/3] video: fbdev: atyfb: clarify ioremap() base and length used

From: "Luis R. Rodriguez" <mcgrof@suse.com>
To: "Ville Syrjälä" <syrjala@sci.fi>, "Borislav Petkov" <bp@suse.de>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Ingo Molnar" <mingo@elte.hu>,
	"Ville Syrjälä" <ville.syrjala@linux.intel.com>,
	"Andy Lutomirski" <luto@amacapital.net>,
	"Tomi Valkeinen" <tomi.valkeinen@ti.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	"Benjamin Herrenschmidt" <benh@kernel.crashing.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	linux-fbdev <linux-fbdev@vger.kernel.org>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	"Dave Airlie" <airlied@redhat.com>,
	"Toshi Kani" <toshi.kani@hp.com>,
	"Suresh Siddha" <sbsiddha@gmail.com>,
	"Linus Torvalds" <torvalds@linux-foundation.org>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Juergen Gross" <jgross@suse.com>,
	"Daniel Vetter" <daniel.vetter@ffwll.ch>,
	"Antonino Daplas" <adaplas@gmail.com>,
	"Jean-Christophe Plagniol-Villard" <plagnioj@jcrosoft.com>,
	"Rob Clark" <robdclark@gmail.com>,
	"Mathias Krause" <minipli@googlemail.com>,
	"Andrzej Hajda" <a.hajda@samsung.com>,
	"Mel Gorman" <mgorman@suse.de>,
	"Vlastimil Babka" <vbabka@suse.cz>,
	"Davidlohr Bueso" <dbueso@suse.de>
Subject: Re: [PATCH v5 1/3] video: fbdev: atyfb: clarify ioremap() base and length used
Date: Thu, 9 Jul 2015 19:25:07 +0200	[thread overview]
Message-ID: <20150709172507.GD7021@wotan.suse.de> (raw)
In-Reply-To: <20150708083849.GB13710@sci.fi>

On Wed, Jul 08, 2015 at 11:38:49AM +0300, Ville Syrjälä wrote:
> On Tue, Jul 07, 2015 at 05:24:57PM -0700, Luis R. Rodriguez wrote:
> > On Thu, Jul 2, 2015 at 4:23 PM, Luis R. Rodriguez <mcgrof@suse.com> wrote:
> > > On Fri, Jun 26, 2015 at 12:30 AM, Borislav Petkov <bp@suse.de> wrote:
> > >> On Fri, Jun 26, 2015 at 03:09:27AM +0200, Luis R. Rodriguez wrote:
> > >>> Sure, mind this as a follow up patch if its too late?
> > >>
> > >> No need, you can send me an updated one - I'll replace it.
> > >
> > > Will do!
> > 
> > OK the commend I'm adding:
> > 
> > @@ -3489,6 +3489,15 @@ static int atyfb_setup_generic(struct pci_dev
> > *pdev, struct fb_info *info,
> > 
> >         /* Map in frame buffer */
> >         info->fix.smem_start = addr;
> > +
> > +       /*
> > +        * The framebuffer is not always 8 MiB that's just the size of the
> > +        * PCI BAR, this is later corrected for use with write-combining
> > +        * helpers with aty_fudge_framebuffer_len() which will adjust the
> > +        * framebuffer accordingly depending on the device.
> 
> That somehow gives me the impression that aty_fudge_framebuffer_len()
> changes smem_len to match the framebuffer size, which it does
> not.
> 
> Dunno, maybe something like this?
> /*
>  * The framebuffer is not always 8 MiB that's just the size of the
>  * PCI BAR. We temporarily abuse smem_len here to store the size
>  * of the BAR. aty_init() will later correct it to match the actual
>  * framebuffer size.
>  *
>  * On devices that don't have the auxiliary register aperture, the
>  * registers are housed at the top end of the framebuffer PCI BAR.
>  * aty_fudge_framebuffer_len() is used to reduce smem_len to not
>  * overlap with the registers.
>  */

Thanks Ville, I used that. Will send out a v6 series.

 Luis