Who can explain the diff between Xserver-1.6.4 version and >1.7 version about the ExaGetPixmapAddress?

Sun Jun 13 01:18:08 PDT 2010

Hi, Maarten,

	After I debug the GeodeAllocOffscreen() operation (it is an internal function), I found it have been replaced exaOffscreenAlloc() with GeodeAllocOffscreen(). 

	About the change, you can see: http://cgit.freedesktop.org/xorg/driver/xf86-video-geode/commit/?id=d681a844e448712a9a419d2a4dca81930d39a80a

	A wholesale update to Randr 1.2 for LX accompanied by massive
cleanup since 08/07/2008, include exaOffscreenAlloc(), because no longer to maintain the gx_video. So you can find the exaOffscreenAlloc on Geode-gx. And now, only need to maintain Geode-LX, I believe the GeodeAllocOffscreen() have been update to a strong effort. It have been allocated the Geode-LX memory, include Compression buffer, TryHWCursor, exaBfSz, EXA offscreen space, a shadow buffer, a video overlay. (you can see in lx_memory.c -> LXInitOffscreen).

	My issue is RandR-unable to rotate. (I have been described the phenomenon in: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-geode/+bug/377929/comments/12 ).

	I have been debug the memory allocation method in LXInitOffscreen. After allocate the EXA offscreen space (http://cgit.freedesktop.org/xorg/driver/xf86-video-geode/tree/src/lx_memory.c#n261 ) 
The crtc shadow frame buffer (Rotate_memory) allocate: 
________
	size -= pScrni->virtualX *
	(pScrni->virtualY * (pScrni->bitsPerPixel >> 3));  
________about 2MB size

The video overlay size is 2MB size.
Then the memorySize = offscreenBase + EXA offscreen Space size 

Steps:
	1). In exaOffscreenInit (Xserver: exa_offscreen.c: 677), the offscreenAreas struct will be allocated. When do rotate action. 
	2). The client program will call the xf86CrtcRotate (In xf86Rotate.c), then it will allocate the Rotate_memory in shadow frame buffer (less than 2MB).
	3). Xf86RotatePrepare -> lx_crtc_shadow_create -> GetScratchPixmapHeader -> exaModifyPixmapHeader_classic, the rotate_memory_base will be loaded into pPixData, the value is equal to memorySize+memoryBase, So "pPixData - pExaScr->info->memoryBase = pExaScr->info->memorySize", but now in Xserver, it only have "<". The judge is not come into existence. The fb_ptr address value is 0x0.

	I think the GeodeAllocOffscreen() memory allocate action is right. Please take a look, I have not find another reason. So I suggest to add "=".

	Looking forward to your reply.

Thanks,
Hunk Cui

-----Original Message-----
From: Maarten Maathuis [mailto:madman2003 at gmail.com] 
Sent: Thursday, June 10, 2010 12:42 AM
To: Cui, Hunk
Cc: xorg-devel at lists.x.org; Huang, FrankR; Writer, Tim; Torres, Rigo
Subject: Re: Who can explain the diff between Xserver-1.6.4 version and >1.7 version about the ExaGetPixmapAddress?

On Wed, Jun 9, 2010 at 1:00 PM, Cui, Hunk <Hunk.Cui at amd.com> wrote:
> Hi, Maarten,
>
>        Thank you very much for your help, I am looking forward to your reply. :)

GeodeAllocOffscreen() is an internal function, exa doesn't know this
memory. The idea is to remove this from src/lx_memory.c:253

--------
	/* Deduct the probable size of a shadow buffer */
	size -= pScrni->virtualX *
	(pScrni->virtualY * (pScrni->bitsPerPixel >> 3));
--------

This will then be added to the exa pool, you can use
exaOffscreenAlloc. See
http://cgit.freedesktop.org/xorg/driver/xf86-video-ati/tree/src/radeon_legacy_memory.c#n50
for appropriate arguments and usage. The offset is relative to memory
base.

The same is true for the video overlay, gx_video seems to be using
exaOffscreenAlloc already.

>
> Thanks,
> Hunk Cui
>
> -----Original Message-----
> From: Maarten Maathuis [mailto:madman2003 at gmail.com]
> Sent: Wednesday, June 09, 2010 6:57 PM
> To: Cui, Hunk
> Cc: xorg-devel at lists.x.org; Huang, FrankR; Writer, Tim; Torres, Rigo
> Subject: Re: Who can explain the diff between Xserver-1.6.4 version and >1.7 version about the ExaGetPixmapAddress?
>
> On Wed, Jun 9, 2010 at 12:37 PM, Cui, Hunk <Hunk.Cui at amd.com> wrote:
>> Hi, Maarten,
>>
>>        About the crtc->rotatedData (AMD Geode LX driver)
>> in http://cgit.freedesktop.org/xorg/driver/xf86-video-geode/tree/src/lx_display.c#n386
>> then the rotate_mem offset and shadow_allocate address will be return to xf86CrtcSetModeTransform, after run to xf86RotatePrepare, it will call lx_crtc_shadow_create -> GetScratchPixmapHeader -> exaModifyPixmapHeader_classic to write the pPixData. The pPixData will be allocated to the sys_ptr and fb_ptr(if the judge come into existence).
>>
>
> I am looking at your driver, and it's all a bit confusing. This will
> have to wait until (at least) this evening.
>
>> Thanks
>> Hunk Cui
>>
>> -----Original Message-----
>> From: Maarten Maathuis [mailto:madman2003 at gmail.com]
>> Sent: Wednesday, June 09, 2010 6:16 PM
>> To: Cui, Hunk
>> Cc: xorg-devel at lists.x.org; Huang, FrankR; Writer, Tim; Torres, Rigo
>> Subject: Re: Who can explain the diff between Xserver-1.6.4 version and >1.7 version about the ExaGetPixmapAddress?
>>
>> On Wed, Jun 9, 2010 at 11:59 AM, Cui, Hunk <Hunk.Cui at amd.com> wrote:
>>> Hi, Maarten,
>>>        You can see my attachment screenshot, in this example, when run to the line 177-178, the pPixData is 0xb62b000, pExaScr->info->memoryBase is 0xb5e2b000,pExaScr->info->memorySize is 17825792, if only have "<", the judge will not come into existence.
>>>        You can try it. If not come into existence. The fb_ptr address value is 0x0.
>>
>> How are you allocating rotatedData?
>>
>>>
>>> Thanks,
>>> Hunk Cui
>>>
>>>
>>> -----Original Message-----
>>> From: Maarten Maathuis [mailto:madman2003 at gmail.com]
>>> Sent: Wednesday, June 09, 2010 5:47 PM
>>> To: Cui, Hunk
>>> Cc: xorg-devel at lists.x.org; Huang, FrankR; Writer, Tim; Torres, Rigo
>>> Subject: Re: Who can explain the diff between Xserver-1.6.4 version and >1.7 version about the ExaGetPixmapAddress?
>>>
>>> On Wed, Jun 9, 2010 at 10:23 AM, Cui, Hunk <Hunk.Cui at amd.com> wrote:
>>>> Hi, Maarten,
>>>>
>>>>         As your commit:
>>>> http://cgit.freedesktop.org/xorg/xserver/commit/?id=12aeddf5ad41902a180f8108623f356642b3e911
>>>>
>>>>         About Scratch pixmap with gpu memory – Framebuffer. Now in > 1.7
>>>> version, the exaModifyPixmapHeader function have been become
>>>> exaModifyPixmapHeader_classic (
>>>> http://cgit.freedesktop.org/xorg/xserver/tree/exa/exa_classic.c?id=ac7ac913fd98ea359c05c89968ab53a3223615b4
>>>> Line 144).
>>>>
>>>>         When I debug to this point (my AMD xf86-video-geode), the line
>>>> 171-172, why only have the “<” judge. For general, I think “((CARD8
>>>> *)pPixData - pExaScr->info->memoryBase) <= pExaScr->info->memorySize)”,
>>>> because rotate_mem offset should equal to the pExaScr->info->memorySize
>>>> (e.g: displayed frame buffer). If only have the “<”, It will not go into
>>>> this judge, so the fb_ptr address value is 0x0, then the value will affect
>>>> the exaGetPixmapOffset function (in exa.c
>>>> http://cgit.freedesktop.org/xorg/xserver/tree/exa/exa.c?id=ac7ac913fd98ea359c05c89968ab53a3223615b4
>>>> line 62) about “return (CARD8 *)pExaPixmap->fb_ptr -
>>>> pExaScr->info->memoryBase”, the range will be exceed, if run the
>>>> driver_do_composite (It is lx_do_composite in our geode_driver), the
>>>> dstOffset is a error value.
>>>>
>>>>         Could you explain this issue? Let me know why only have “<”.
>>>
>>> If your memory base is 20000, your offscreen memory size is 10000,
>>> then 20000 to 29999 are valid addresses. If you enter 30000 - 10000 <=
>>> 20000, then that would be true, which is wrong, that's why it's just
>>> "<", because addressing starts from 0 not 1.
>>>
>>>>
>>>> Thanks,
>>>>
>>>> Hunk Cui
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> Life spent, a precious moment, in the wink of an eye we live and we die.
>>>
>>>
>>
>>
>>
>> --
>> Life spent, a precious moment, in the wink of an eye we live and we die.
>>
>>
>
>
>
> --
> Life spent, a precious moment, in the wink of an eye we live and we die.
>
>

-- 
Life spent, a precious moment, in the wink of an eye we live and we die.