On Mon, Jan 25, 2016 at 7:49 PM, Rob Clark <robdclark@xxxxxxxxx> wrote:
> from a quick look, I think so..
>
> It was something I ran across on an older kernel which didn't have
> amdgpu, but I don't see anything obvious that would cause
> drm_fb_helper_init() to be skipped in amdgpu if there are no
> connectors.. (but nouveau seems to check for
> dev->mode_config.num_crtc, for (I assume) similar reasons)
We don't enable fbdev on amdgpu if the chip in question has no display
block, but we still could enable it if the chip has a display block,
but no connectors. The same may be true in nouveau so the check for
num_crtc may not be enough. Attached patch should rectify that.
Alex
>
> BR,
> -R
>
> On Mon, Jan 25, 2016 at 6:57 PM, Mike Lothian <mike@xxxxxxxxxxxxxx> wrote:
>> Is something similar required for AMDGPU too?
>>
>> On Mon, 25 Jan 2016 at 23:06 Rob Clark <robdclark@xxxxxxxxx> wrote:
>>>
>>> This fixes an issue that was noticed on an optimus/prime laptop with
>>> a kernel that was old enough to not support the integrated intel gfx
>>> (which was driving all the outputs), but did have support for the
>>> discrete radeon gpu. The end result was not falling back to VESA and
>>> leaving the user with a black screen.
>>>
>>> (Plus it is kind of silly to create an framebuffer device if there
>>> are no outputs hooked up to the gpu.)
>>>
>>> Signed-off-by: Rob Clark <robdclark@xxxxxxxxx>
>>> ---
>>> drivers/gpu/drm/radeon/radeon_display.c | 6 ++++--
>>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/radeon/radeon_display.c
>>> b/drivers/gpu/drm/radeon/radeon_display.c
>>> index 1eca0ac..f8e776c 100644
>>> --- a/drivers/gpu/drm/radeon/radeon_display.c
>>> +++ b/drivers/gpu/drm/radeon/radeon_display.c
>>> @@ -1670,8 +1670,10 @@ int radeon_modeset_init(struct radeon_device *rdev)
>>> /* setup afmt */
>>> radeon_afmt_init(rdev);
>>>
>>> - radeon_fbdev_init(rdev);
>>> - drm_kms_helper_poll_init(rdev->ddev);
>>> + if (!list_empty(&rdev->ddev->mode_config.connector_list)) {
>>> + radeon_fbdev_init(rdev);
>>> + drm_kms_helper_poll_init(rdev->ddev);
>>> + }
>>>
>>> /* do pm late init */
>>> ret = radeon_pm_late_init(rdev);
>>> --
>>> 2.5.0
>>>
>>> _______________________________________________
>>> dri-devel mailing list
>>> dri-devel@xxxxxxxxxxxxxxxxxxxxx
>>> http://lists.freedesktop.org/mailman/listinfo/dri-devel
> _______________________________________________
> dri-devel mailing list
> dri-devel@xxxxxxxxxxxxxxxxxxxxx
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
From 55a9c63c7a20f07cb77864346ac21ea962f00068 Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher@xxxxxxx>
Date: Tue, 26 Jan 2016 00:30:33 -0500
Subject: [PATCH] drm/amdgpu: don't init fbdev if we don't have any connectors
Don't init fbdev if we don't have connectors. E.g., if you have
a PX laptop with the displays attached to an IGP with no driver
support, you may end up with a blank screen rather than falling
back to vesa, etc.
Based on a similar radeon patch from Rob Clark.
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
index cfb6caa..9191467 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
@@ -333,6 +333,10 @@ int amdgpu_fbdev_init(struct amdgpu_device *adev)
if (!adev->mode_info.mode_config_initialized)
return 0;
+ /* don't init fbdev if there are no connectors */
+ if (list_empty(&adev->ddev->mode_config.connector_list))
+ return 0;
+
/* select 8 bpp console on low vram cards */
if (adev->mc.real_vram_size <= (32*1024*1024))
bpp_sel = 8;
--
2.5.0
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
http://lists.freedesktop.org/mailman/listinfo/dri-devel
