From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH] drm/i915: Fixup hpd irq register setup ordering Date: Sun, 9 Dec 2012 20:17:54 +0100 Message-ID: <20121209191754.GG11556@phenom.ffwll.local> References: <1355080498-3870-1-git-send-email-daniel.vetter@ffwll.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ea0-f177.google.com (mail-ea0-f177.google.com [209.85.215.177]) by gabe.freedesktop.org (Postfix) with ESMTP id 0EFC3E5C89 for ; Sun, 9 Dec 2012 11:16:23 -0800 (PST) Received: by mail-ea0-f177.google.com with SMTP id c10so817540eaa.36 for ; Sun, 09 Dec 2012 11:16:23 -0800 (PST) Content-Disposition: inline In-Reply-To: <1355080498-3870-1-git-send-email-daniel.vetter@ffwll.ch> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Intel Graphics Development Cc: Daniel Vetter List-Id: intel-gfx@lists.freedesktop.org On Sun, Dec 09, 2012 at 08:14:58PM +0100, Daniel Vetter wrote: > For GMCH platforms we set up the hpd irq registers in the irq > postinstall hook. But since we only enable the irq sources we actually > need in PORT_HOTPLUG_EN/STATUS, taking dev_priv->hotplug_supported_mask > into account, no hpd interrupt sources is enabled since > > commit 52d7ecedac3f96fb562cb482c139015372728638 > Author: Daniel Vetter > Date: Sat Dec 1 21:03:22 2012 +0100 > > drm/i915: reorder setup sequence to have irqs for output setup > > Wrongly set-up interrupts also lead broken hw-based load-detection on > at least GM45, resulting in ghost VGA/TV-out outputs. > > To fix this, delay the hotplug register setup until after all outputs > are set up, by moving it into a new dev_priv->display.hpd_irq_callback. > We might also move the PCH_SPLIT platforms to such a setup eventually. > > Another funny part is that we need to delay the fbdev initial config > probing until after the hpd regs are setup, for otherwise it'll detect > ghost outputs. But we can only enable the hpd interrupt handling > itself (and the output polling) _after_ that initial scan, due to > massive locking brain-damage in the fbdev setup code. Add a big > comment to explain this cute little dragon lair. > > Reported-by: Chris Wilson > Signed-off-by: Daniel Vetter Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=54943 -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch