drm/i915: Attach a fb to the load-detect pipe
authorChris Wilson <chris@chris-wilson.co.uk>
Tue, 19 Apr 2011 07:36:26 +0000 (08:36 +0100)
committerKeith Packard <keithp@keithp.com>
Tue, 10 May 2011 20:19:18 +0000 (13:19 -0700)
commitd2dff872ac44540622ef77a2b7d6ce4a1b145931
treec66cb740139e9793b39d6d0731eebc6b3a53b85f
parent0622a53c60fbf48d3b85efc4995f4c152c254cf4
drm/i915: Attach a fb to the load-detect pipe

We need to ensure that we feed valid memory into the display plane
attached to the pipe when switching the pipe on. Otherwise, the display
engine may read through an invalid PTE and so throw an PGTBL_ER
exception.

As we need to perform load detection before even the first object is
allocated for the fbdev, there is no pre-existing object large enough
for us to borrow to use as the framebuffer. So we need to create one
and cleanup afterwards. At other times, the current fbcon may be large
enough for us to borrow it for duration of load detection.

Found by assert_fb_bound_for_plane().

Reported-by: Knut Petersen <Knut_Petersen@t-online.de>
References: https://bugs.freedesktop.org/show_bug.cgi?id=36246
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Keith Packard <keithp@keithp.com>
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/i915/intel_drv.h