RE: Memory allocation in Video4Linux

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I remember some Continous Memory Allocator (CMA) being iterated down a few versions on 
some mailing lists? IIRC, it is also for large buffers and management for video IPs.

Cheers!

> -----Original Message-----
> From: umg-meego-handset-kernel-bounces@xxxxxxxxxxxxxxxxxxxxxxx [mailto:umg-
> meego-handset-kernel-bounces@xxxxxxxxxxxxxxxxxxxxxxx] On Behalf Of Wang, Wen W
> Sent: Wednesday, February 09, 2011 12:03 PM
> To: Yang, Jianwei; linux-media@xxxxxxxxxxxxxxx; umg-meego-handset-
> kernel@xxxxxxxxxxxxxxxxxxxxxxx
> Cc: Jozef Kruger
> Subject: Re: [Umg-meego-handset-kernel] Memory allocation in Video4Linux
> 
> Yes. Some are internal frame and yuv444 is the output.
> 
> >-----Original Message-----
> >From: Yang, Jianwei
> >Sent: 2011年2月9日 14:31
> >To: Wang, Wen W; linux-media@xxxxxxxxxxxxxxx;
> >umg-meego-handset-kernel@xxxxxxxxxxxxxxxxxxxxxxx
> >Cc: Jozef Kruger
> >Subject: RE: Memory allocation in Video4Linux
> >
> >Curious for the below, why it is a sum? Will you use all of format at the same time?
> >
> >> 	1 RAW16: 2*14 = 28MB
> >> 	1 qplane6: 6/4 * 14 = 21MB
> >> 	1 yuv420_16: 2 * 1.5 * 14 = 42MB
> >> 	1 yuv420: 1.5 * 14 = 21MB
> >> 	1 yuv444: 3 * 14 = 42MB
> >> 	total: 154MB.
> >
> >> -----Original Message-----
> >> From: umg-meego-handset-kernel-bounces@xxxxxxxxxxxxxxxxxxxxxxx
> >> [mailto:umg-meego-handset-kernel-bounces@xxxxxxxxxxxxxxxxxxxxxxx] On
> >> Behalf Of Wang, Wen W
> >> Sent: Wednesday, February 09, 2011 2:23 PM
> >> To: linux-media@xxxxxxxxxxxxxxx; umg-meego-handset-
> >> kernel@xxxxxxxxxxxxxxxxxxxxxxx
> >> Cc: Jozef Kruger
> >> Subject: [Umg-meego-handset-kernel] Memory allocation in Video4Linux
> >>
> >> Hi,
> >>
> >> We are developing the image processor driver for Intel Medfield platform.
> >>
> >> We have received some comments on memory management that we should use
> >> standard Linux kernel interfaces for this, since we are doing everything
> >> by ourselves including memory allocation (based on pages), page table
> >> management, virtual address management and etc.
> >>
> >> So can you please help give some advice or suggestion on using standard
> >> kernel interface for memory management?
> >>
> >> The processor has a MMU on-chip with same virtual address range as IA. The
> >> processor will access system memory (read and write) through MMU and page
> >> table. The memory consumption of the driver could be quite big especially
> >> for high resolution (14MP) with certain features turned on.
> >> For example: advanced ISP with XNR and yuv444 output, at 14MP this uses:
> >> 	1 RAW16: 2*14 = 28MB
> >> 	1 qplane6: 6/4 * 14 = 21MB
> >> 	1 yuv420_16: 2 * 1.5 * 14 = 42MB
> >> 	1 yuv420: 1.5 * 14 = 21MB
> >> 	1 yuv444: 3 * 14 = 42MB
> >> 	total: 154MB.
> >>
> >> Thanks
> >> Wen
> >> _______________________________________________
> >> Umg-meego-handset-kernel mailing list
> >> Umg-meego-handset-kernel@xxxxxxxxxxxxxxxxxxxxxxx
> >> http://umglistsvr.jf.intel.com/mailman/listinfo/umg-meego-handset-kernel
> _______________________________________________
> Umg-meego-handset-kernel mailing list
> Umg-meego-handset-kernel@xxxxxxxxxxxxxxxxxxxxxxx
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