From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 18 Aug 2000 23:47:49 -0700 From: Daniel Jacobowitz To: linuxppc-dev@lists.linuxppc.org Subject: Re: Control fb problem on 8500 Message-ID: <20000818234749.A7999@drow.them.org> References: <200008182102.XAA00828@piglet.grunz.lu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <200008182102.XAA00828@piglet.grunz.lu>; from mlan@cpu.lu on Fri, Aug 18, 2000 at 11:02:25PM +0200 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Fri, Aug 18, 2000 at 11:02:25PM +0200, Michel Lanners wrote: > I've also had a look at what changed on control from earlier versions, > and found only the pitch of the lines that changed. > > In fact, before, the line length was exactly hpixels * bytes/pixel, > whereas now there's an additional 0x20 bytes in each line. I have not > been able to boot a 2.4.0 kernel with any fix applied, but you could try > and build a version without those 0x20 bytes added (they are found in a > few spots inside controlfb.c). > > As to why these 0x20 bytes were added, anybody know an explanation? And, > if they do serve a purpose (I suppose so ;-), it would be better to add > the exact number of bytes as a #define somewhere... *sigh* I have no idea where this came from, but 0x20 means it has something to do with cursor support, I'd bet. I seem to recall someone talking about that a few months ago... that is how hardware cursor is generally implemented, by a 32 pixel block at the end of the scanline. Dan the underactive and out of touch controlfb maintainer /--------------------------------\ /--------------------------------\ | Daniel Jacobowitz |__| SCS Class of 2002 | | Debian GNU/Linux Developer __ Carnegie Mellon University | | dan@debian.org | | dmj+@andrew.cmu.edu | \--------------------------------/ \--------------------------------/ ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/