From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [Linux-fbdev-devel] radeonfb lockup in .28-rc (bisected) Date: Wed, 05 Nov 2008 08:36:00 +1100 Message-ID: <1225834560.8004.275.camel@pasglop> References: <1225152347.8004.49.camel@pasglop> <1225662539.8004.237.camel@pasglop> <871vxtthr3.fsf@burly.wgtn.ondioline.org> <1225697689.8004.245.camel@pasglop> <87wsfkrnn1.fsf@burly.wgtn.ondioline.org> Reply-To: benh@kernel.crashing.org Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <87wsfkrnn1.fsf@burly.wgtn.ondioline.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Paul Collins Cc: James Cloos , linux-fbdev-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Andrew Morton , Linus Torvalds , "David S. Miller" , Krzysztof Halasa On Tue, 2008-11-04 at 19:49 +1300, Paul Collins wrote: > Benjamin Herrenschmidt writes: > > > One thing you may want to try .. it will result in crap results on > > screen but would help telling us if that's the cause, is to hack > > radeonfb to round the image size to a multiple of 32 and see if that > > stops the lockup. > > I took a guess at how to do this and ended up with the patch below. > > With the patch applied, the screen turns almost completely to gibberish > at console handover and the machine hangs. At the top I get two lines > of old output from the previous boot. (I'm pretty sure it's hung > because the optical drive init happens after console handover, and I > don't get the usual chunka-chunka noise.) > > The corruption I get is very similar to what I got when I originally > reported the problem when I was using my patched-in 12x24 font. (I > created the .psf version later and switched back to default 8x16 to > verify my problem was the same as James's.) > > > diff --git a/drivers/video/aty/radeon_accel.c b/drivers/video/aty/radeon_accel.c > index 8718f73..848e9bc 100644 > --- a/drivers/video/aty/radeon_accel.c > +++ b/drivers/video/aty/radeon_accel.c > @@ -208,7 +208,11 @@ static void radeonfb_prim_imageblit(struct radeonfb_info *rinfo, > * work ok for me without that and the doco doesn't seem to imply > * there is such a restriction. > */ > - OUTREG(DST_WIDTH_HEIGHT, (image->width << 16) | image->height); > + { > + /* Hack attack. */ > + int width = ((image->width - 1) / 32 + 1) * 32; > + OUTREG(DST_WIDTH_HEIGHT, (width << 16) | image->height); > + } > > src_bytes = (((image->width * image->depth) + 7) / 8) * image->height; > dwords = (src_bytes + 3) / 4; Oh and you also need to change the src_bytes calculation Ben. >