Hi Ilyes,

>But still, you guys need assistance from the kernel-space to
>resolve the phys. addresses related to those malloc'ed buffers
>(which aren't necessarily contiguous in phys. RAM), so that to
>populate the GPU MMU, right?

Yes.

>Is it the case? If yes, is this done in gfxdriver or the
>system driver (via a dedicated surface pool)?

Neither.  As I tried to note previously, there are underlying
graphics drivers (that exist in both user and kernel mode which
are not part of DFB) that are used/called by the DFB graphics
drivers.  For example:

                  App
                   |
               DFB core
                   |
          DFB graphics driver
                   |
         Custom graphics driver
        such as an OGL ES driver
         with custom extensions
                   |
  User             |
  =====================================
  Kernel           |
                   |
        Custom graphics driver KO

There is no dedicated surface pool for system memory surfaces.

Cheers,
Timothy

>-----Original Message-----
>From: Ilyes Gouta [mailto:ilyes.go...@gmail.com] 
>Sent: Friday, July 01, 2011 2:01 PM
>To: Strelchun, Timothy
>Cc: directfb-dev@directfb.org
>Subject: Re: [directfb-dev] [PATCH] GPU system memory support 
>mods for aligned buffer directfbrc commands (was RE: [PATCH] 3 
>patch set...)
>
>Hi Timothy,
>
>> It is not shared with the CPU MMU and is instead part of the 
>GPU unit 
>> on our different SOCs.  We do not provide replacements for DFB's 
>> memory allocation functions.  The underlying graphics 
>drivers used by 
>> our DFB graphics drivers handle setting up the needed GPU 
>MMU mappings for the malloc'd memory pages (which are locked 
>and cannot move) and hide that complexity from the DFB layer.
>
>But still, you guys need assistance from the kernel-space to 
>resolve the phys. addresses related to those malloc'ed buffers 
>(which aren't necessarily contiguous in phys. RAM), so that to 
>populate the GPU MMU, right?
>
>Is it the case? If yes, is this done in gfxdriver or the 
>system driver (via a dedicated surface pool)?
>
>Thanks for bearing with me!
>
>-Ilyes
>
>>
>> Cheers,
>> Timothy
>>
>>>-----Original Message-----
>>>From: Ilyes Gouta [mailto:ilyes.go...@gmail.com]
>>>Sent: Wednesday, June 22, 2011 1:19 AM
>>>To: Strelchun, Timothy
>>>Cc: directfb-dev@directfb.org
>>>Subject: Re: [directfb-dev] [PATCH] GPU system memory 
>support mods for 
>>>aligned buffer directfbrc commands (was RE: [PATCH] 3 patch set...)
>>>
>>>Hi Timothy,
>>>
>>>Out of curiosity, is that blitter MMU kind of "shared" with 
>the CPU's 
>>>MMU? or do you guys provide your own replacements for 
>>>malloc()/realloc()/free(), for DirectFB?
>>>
>>>Thanks,
>>>
>>>-Ilyes
>>>
>>>On Tue, Jun 21, 2011 at 11:31 PM, Strelchun, Timothy 
>>><timothy.strelc...@intel.com> wrote:
>>>> Hi Ilyes,
>>>>
>>>>>Is your h/w blitter able to cope with the virtual 
>addresses (as seen 
>>>>>within the user-space process) of the DirectFB surfaces?
>>>>
>>>> Yes, that is correct.  Any graphics driver that reports
>>>support for system memory surfaces would need to have a way to deal 
>>>with the non-physically contiguous (virtual) memory associated with 
>>>them (such as via their own MMU that's setup by the driver).
>>>>
>>>> Cheers,
>>>> Timothy
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