The RandR-"unable to set rotation" issue in AMD Geode LX platform

[Alex Deucher]

On Wed, Jun 2, 2010 at 7:15 AM, Cui, Hunk <Hunk.Cui at amd.com> wrote:
> Hi, Alex,
>
>        I have been established three Xorg environments, only use the XRandR client program (it can download from http://cgit.freedesktop.org/xorg/ ).
> The phenomenon, see below:
> 1).Xserver-1.6.4/Geode driver-2.11.7
>        Run: xrandr --output default --rotate left
>        Phenomenon: The screen properly rotate
>        Run: xrandr --output default --rotate normal --auto
>        Phenomenon: The screen return to normal state
> 2).Xserver-1.7.1/Geode driver-2.11.7
>        Run: xrandr --output default --rotate left
>        Phenomenon: The screen turn to black
>        Run: xrandr --output default --rotate normal --auto
>        Phenomenon: The screen return to normal state
> 3).Xserver-1.8.99/Geode driver-2.11.8
>        Run: xrandr --output default --rotate left
>        Phenomenon: The screen turn to black
>        Run: xrandr --output default --rotate normal --auto
>        Phenomenon: The screen does not return to normal state, still black
>
>        Now the problem become more and more urgent, I use ddd tools to trace the part of Xserver.
>
>        In Xserver-1.6.4, I trace the source about the composite operation, as following:
>
> #0  lx_do_composite (pxDst=0x8bef7f0, srcX=0, srcY=0, maskX=13860, maskY=-1740, dstX=0, dstY=0, width=1024, height=768) at lx_exa.c:992
> #1  exaTryDriverComposite (op=<value optimized out>, pSrc=<value optimized out>, pMask=0x0, pDst=0x8bb41c0, xSrc=0, ySrc=0, xMask=<value optimized out>, yMask=<value optimized out>, xDst=<value optimized out>, yDst=<value optimized out>, width=<value optimized out>, height=<value optimized out>) at exa_render.c:688
> #2  exaComposite (op=1 '\001', pSrc=0x8bb2fc0, pMask=0x0, pDst=0x8bb41c0, xSrc=0, ySrc=0, xMask=0, yMask=0, xDst=0, yDst=0, width=1024, height=768) at exa_render.c:935
> #3  damageComposite (op=0 '\000', pSrc=0x8bb2fc0, pMask=0x0, pDst=0x8bb41c0, xSrc=<value optimized out>, ySrc=<value optimized out>, xMask=<value optimized out>, yMask=<value optimized out>, xDst=<value optimized out>, yDst=<value optimized out>, width=<value optimized out>, height=<value optimized out>) at damage.c:643
> #4  CompositePicture (op=1 '\001', pSrc=0x8bb2fc0, pMask=0x0, pDst=0x8bb41c0, xSrc=0, ySrc=0, xMask=<value optimized out>, yMask=<value optimized out>, xDst=<value optimized out>, yDst=<value optimized out>, width=1024, height=768) at picture.c:1675
> #5  xf86RotateCrtcRedisplay (screenNum=0, blockData=0x0, pTimeout=0xbfaa3aec, pReadmask=0x81ef240) at xf86Rotate.c:118
> #6  xf86RotateRedisplay (screenNum=0, blockData=0x0, pTimeout=0xbfaa3aec, pReadmask=0x81ef240) at xf86Rotate.c:249
> #7  xf86RotateBlockHandler (screenNum=0, blockData=0x0, pTimeout=0xbfaa3aec, pReadmask=0x81ef240) at xf86Rotate.c:269
> #8  BlockHandler (pTimeout=0xbfaa3aec, pReadmask=0x81ef240) at dixutils.c:384
> #9  WaitForSomething (pClientsReady=0x8be4900) at WaitFor.c:215
> #10 Dispatch () at dispatch.c:386
> #11 main (argc=1, argv=0xbfaa3c84, envp=0xbfaa3c8c) at main.c:397
>
>        The lx_do_composite function is the Geode-driver function, the others are the XServer function, when I replace to the Xsever1.7.1 or Xserver1.8.99, the maskX and maskY values are 0. That make me doubt it. Can you have some other opinion? And you said the shadow_create, What is mean about it?
>

As Michel said, the mask isn't used for this operation so ignore the
the mask parameters.  It's src/dst only.  As I noted before, if
rotation is enabled, you need to make sure:
- you deal with transforms correctly in the driver composite hook, or
fallback and let software handle it
- you point the crtc offset at the offset of the rotation shadow buffer

Alex

> Thanks,
> Hunk Cui
>
> -----Original Message-----
> From: Alex Deucher [mailto:alexdeucher at gmail.com]
> Sent: Thursday, May 27, 2010 10:57 PM
> To: Cui, Hunk
> Cc: xorg-devel at lists.x.org; xorg at lists.freedesktop.org; Kai-Uwe Behrmann; Adam Jackson; yangman at gmail.com
> Subject: Re: The RandR-"unable to set rotation" issue in AMD Geode LX platform
>
> On Wed, May 26, 2010 at 11:40 PM, Cui, Hunk <Hunk.Cui at amd.com> wrote:
>> Hi, all,
>>
>> As said on Ubuntu BTS,
>> https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-geode/+bug/377929
>>
>> About “unable to set rotation on AMD Geode LX800”, I used Ubuntu 9.10 which
>> comes with generic kernel 2.6.31-17 and Xserver 1.6.4, geode-driver 2.11.6,
>> I also able to rotate the screen just fine with the default geode driver
>> that comes with this distribution using Xrandr. Rotation is working just
>> fine with 'xrandr'. I used command such as:
>>> xrandr -o left
>>> xrandr -o right
>>> xrandr -o inverted
>>> xrandr -o normal
>>
>> I gave a try with 1.7.1 server on rotation, Geode driver 2.11.7, In our
>> platform, the <OUTPUT> name is "default",
>> (BTW: In general use $ xrandr -q to discover the appropriate output names
>> for your configuration, the reference link:
>> http://www.thinkwiki.org/wiki/Xorg_RandR_1.2)
>>
>> When I tried: "xrandr --output default --rotate left". The screen turn to
>> black.
>> Then tried: "xrandr --output default --rotate normal --auto". The screen
>> return to normal.
>>
>> Because from 1.6.4 server to 1.7.1 server, the part of RandR have been
>> updated and changed from source code.
>>
>> Who know the change about the part of RandR in Xserver 1.7.1?
>
> I don't recall what might have changed with regard to rotation in
> xserver 1.7.1 off hand.  However, randr-based rotation is implemented
> via composite.  If your driver implements EXA, the EXA composite hook
> would be used, so you need to make sure your composite hook handles
> transforms or if not falls back properly so it can be handled by
> software.  Also make sure you implement the randr crtc hooks for
> allocating the shadow pixmap used for rotation (shadow_create,
> shadow_allocate, shadow_destroy).  Finally in your crtc mode_set
> function, make sure you set the crtc base address to the shadow buffer
> is rotation is active.
>
> Alex
>
>