RE: Memory allocation in Video4Linux
Hi Laurent,
You make this very clear, thank you!
The ISP on Medfield do have its own IOMMU. And I also think an IOMMU layer for
ISP is needed.
I'm not quite understand unless hardware design doesn't give you a choice
about that,. Can you explain more on that?
Also regarding to the VCMM (Virtual Contiguous Memory Manager) or CMA, is it
also an option?
Thanks
Wen
-Original Message-
From: Laurent Pinchart [mailto:laurent.pinch...@ideasonboard.com]
Sent: 2011年2月10日 17:29
To: Gao, Bin
Cc: Wang, Wen W; Kanigeri, Hari K; Iyer, Sundar; Yang, Jianwei;
linux-media@vger.kernel.org; umg-meego-handset-ker...@umglistsvr.jf.intel.com;
Jozef Kruger
Subject: Re: Memory allocation in Video4Linux
Hi Wen,
On Thursday 10 February 2011 08:59:38 Gao, Bin wrote:
Penwell has IOMMU feature?
As far as I know only part of Intel server processors have this feature
which is designed originally for VT(virtualization technology).
Wen,
Can you refer to other ISP Soc drivers and see how they are dealing with
this issue? I don't understand why you need to manage MMU inside ISP, I
think the real problem is how can we allocate a large number of memory
pages from IA side where ISP can access to by DMA. Any ISP document can be
shared to help us understand what's the problem?
I second this request. It's not totally clear to me from this mail thread
whether your ISP has its own MMU (which would then be considered as an IOMMU),
or accesses the system memory through other means (continuous buffers,
scatter-gather lists, ...).
If the Medfield ISP includes an IOMMU, the IOMMU layer is probably what you
want to use. Memory can then be allocated using a simple vmalloc(), and pages
can be mapped to the ISP memory space using the IOMMU.
Please note that, unless the ISP IOMMU is already supported by the Linux
kernel, you will obviously need to implement an IOMMU driver for it. What you
shouldn't do is put that code in the ISP driver (unless hardware design
doesn't give you a choice about that, but I need to see more documentation to
answer this question).
--
Regards,
Laurent Pinchart
N�Р骒r��yb�X�肚�v�^�)藓{.n�+�伐�{���bj)��骅w* jg�报 �茛j/�赇z罐���2���ㄨ���)摺�a囤�� �G���h��j:+v���w��佶
Re: Memory allocation in Video4Linux
Hi Wen, On Thursday 10 February 2011 10:44:58 Wang, Wen W wrote: Hi Laurent, You make this very clear, thank you! The ISP on Medfield do have its own IOMMU. And I also think an IOMMU layer for ISP is needed. I'm not quite understand unless hardware design doesn't give you a choice about that,. Can you explain more on that? Basically, Linux aims for driver reusability. That means that separate pieces of hardware, even when they are designed to work together, should be handled by separate, indepedent drivers. This might make the initial development a bit longer, as proper abstraction APIs need to be designed when they don't exist, but it cuts down time to market later when a hardware block is reused in a different silicon or board. A good example of that approach is I2C sensors. They're supported by drivers that are completely independent of the ISP they are connected to, and use the V4L2 subdev in-kernel API to communicate with the ISP in a hardware-indepedent way. IOMMU is such an API. It lets you implement support for your particular IOMMU in a self-contained drivers, which can then be used by device drivers (such as the ISP driver). For this to work, the hardware needs to have at least some level of separation between the different components. With I2C that's easy, the sensor can be controlled completely indepedently from the ISP. With the ISP IOMMU, it would more or less depend on how the registers are layed out in memory. If the ISP IOMMU registers are grouped together and separated from the other ISP registers, you should be fine. If they are mixed with ISP registers (an hypotetical bad case would for instance be if the ISP IOMMU required you to set bits in the TLB entries that describe the format of the video data stored in a page), such an abstraction would be much more difficult to achieve, and sometimes even impossible. Also regarding to the VCMM (Virtual Contiguous Memory Manager) or CMA, is it also an option? I'm not sure about VCMM, it seems to be an attempt to unify memory management across IOMMUs and system MMU. I don't think you need to worry about it now, IOMMU should be enough for your needs. CMA, as its name implies, is a contiguous memory allocator. As your ISP has an IOMMU, you don't need to allocate contiguous memory, so CMA isn't useful for your hardware. -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Memory allocation in Video4Linux
Hi Bin, the ISP in Medfield has it's own MMU. This needs to be programmed. So in fact we have 2 problems: 1. how to allocate large memory address space (allocating pages is not the problem). 2. if we re-use OS functionality for this, we need to keep the ISP MMU up to date. This means it needs to be programmed with the L1 page table base address and the TLB needs to be flushed whenever something changes in the page tables. I don't think you need any ISP specific documentation for this. The ISP MMU behaves the same as the IA MMU does. Best regards, Jozef On 02/09/2011 11:59 PM, Gao, Bin wrote: Penwell has IOMMU feature? As far as I know only part of Intel server processors have this feature which is designed originally for VT(virtualization technology). Wen, Can you refer to other ISP Soc drivers and see how they are dealing with this issue? I don't understand why you need to manage MMU inside ISP, I think the real problem is how can we allocate a large number of memory pages from IA side where ISP can access to by DMA. Any ISP document can be shared to help us understand what's the problem? -Bin -Original Message- From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Wang, Wen W Sent: Tuesday, February 08, 2011 11:27 PM To: Kanigeri, Hari K; Iyer, Sundar; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego-handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: Re: [Umg-meego-handset-kernel] Memory allocation in Video4Linux Hi Hari, You are right. What we need is virtual address. Currently we alloc pages (alloc_pages()) for any request. Store those pages for an image buffer into a list. We also manage the virtual address for ISP by ourself (the range from 0 to 4GB) and the page table for our MMU which is independent to system MMU page table. Thanks Wen -Original Message- From: Kanigeri, Hari K Sent: 2011年2月9日 15:22 To: Iyer, Sundar; Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego-handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: RE: Memory allocation in Video4Linux -Original Message- From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Iyer, Sundar Sent: Wednesday, February 09, 2011 12:20 PM To: Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego- handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: Re: [Umg-meego-handset-kernel] Memory allocation in Video4Linux 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. I believe CMA is for allocating physically contiguous memory and from what Wen mentioned he also needs virtual memory management, which the IOMMU will provide. Please check the open source discussion on CMA, the last I heard CMA proposal was shot down. Reference: http://www.spinics.net/lists/linux-media/msg26875.html Wen, how are you currently allocating physical memory ? Thank you, Best regards, Hari ___ Umg-meego-handset-kernel mailing list umg-meego-handset-ker...@umglistsvr.jf.intel.com http://umglistsvr.jf.intel.com/mailman/listinfo/umg-meego-handset-kernel -- Jozef Kruger Senior Customer Solutions Architect Silicon Hive Inc. 2025 Gateway Place, Suite 230 San Jose, CA 95110 phone: +1 408 512 2969 cell: +1 408 644 7533 fax: +1 408 437 6014 jozef.kru...@siliconhive.com http://www.siliconhive.com -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Memory allocation in Video4Linux
Wang, Wen W wrote: Hi Hans, Thanks for your point and videobuf2 is also what I want to use. But since our development kernel version right now is still 2.6.35, I need to find way to work with current videobuf framework. Hi Wen, If you're bound to use that kernel version, then one option to consider might be backporting the videobuf2 to that kernel. 2.6.35 isn't so old. You'd save work by not implementing the buffer handling on your own AND also, you wouldn't later need to port the driver to use videobuf2. I would suggest not to start using the old videobuf at this point. With the current ISPs with their own MMUs it really does more harm than good. Regards, -- Sakari Ailus sakari.ai...@maxwell.research.nokia.com -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Memory allocation in Video4Linux
Hi Han,
Thank you very much. I will check the link.
Thanks
Wen
-Original Message-
From: Jonghun Han [mailto:jonghun@samsung.com]
Sent: 2011年2月9日 15:58
To: 'Hans Verkuil'; Wang, Wen W; 'Jozef Kruger'
Cc: Kanigeri, Hari K; Iyer, Sundar; Yang, Jianwei; linux-media@vger.kernel.org;
조경호/S/W Solution개발팀(S.LSI)/E4(선임)/삼성전자
Subject: RE: Memory allocation in Video4Linux
Hi,
Maybe VCM is helpful for you. Please refer to the following URL.
http://marc.info/?l=linux-mmm=129255940319217w=2
Best regards,
Jonghun Han
Wednesday, February 09, 2011 4:52 PM Hans Verkuil wrote:
-Original Message-
From: linux-media-ow...@vger.kernel.org [mailto:linux-media-
ow...@vger.kernel.org] On Behalf Of Hans Verkuil
Sent: Wednesday, February 09, 2011 4:52 PM
To: Wang, Wen W; Jozef Kruger
Cc: Kanigeri, Hari K; Iyer, Sundar; Yang, Jianwei;
linux-media@vger.kernel.org
Subject: Re: Memory allocation in Video4Linux
On Wednesday, February 09, 2011 08:27:27 Wang, Wen W wrote:
Hi Hari,
You are right. What we need is virtual address.
Currently we alloc pages (alloc_pages()) for any request. Store those
pages for
an image buffer into a list. We also manage the virtual address for ISP by
ourself
(the range from 0 to 4GB) and the page table for our MMU which is
independent to
system MMU page table.
Assuming you are using video4linux for this driver, then you should take a
look at
the new videobuf2 framework that will appear in 2.6.39. It is already in the
media
tree (http://git.linuxtv.org/media_tree.git, see
include/media/videobuf2-core.h).
It is much better than the old videobuf framework, and in particular gives
the driver
much more control on how memory is allocated and used.
Regards,
Hans
Thanks
Wen
-Original Message-
From: Kanigeri, Hari K
Sent: 2011年2月9日 15:22
To: Iyer, Sundar; Wang, Wen W; Yang, Jianwei;
linux-media@vger.kernel.org;
umg-meego-handset-ker...@umglistsvr.jf.intel.com
Cc: Jozef Kruger
Subject: RE: Memory allocation in Video4Linux
-Original Message-
From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com
[mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com]
On Behalf Of Iyer, Sundar
Sent: Wednesday, February 09, 2011 12:20 PM
To: Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org;
umg-meego- handset-ker...@umglistsvr.jf.intel.com
Cc: Jozef Kruger
Subject: Re: [Umg-meego-handset-kernel] Memory allocation in
Video4Linux
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.
I believe CMA is for allocating physically contiguous memory and from
what Wen mentioned he also needs virtual memory management, which the
IOMMU will provide. Please check the open source discussion on CMA,
the last I heard CMA proposal was shot down.
Reference: http://www.spinics.net/lists/linux-media/msg26875.html
Wen, how are you currently allocating physical memory ?
Thank you,
Best regards,
Hari
翳 .n +% 遍荻 w .n 伐 {炳g n r■ ㄨ｛ 夸z罐
zf＂
赙z_璁 :+v )撸
--
Hans Verkuil - video4linux developer - sponsored by Cisco
--
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Re: Memory allocation in Video4Linux
Hi Wen, Em 09-02-2011 04:23, Wang, Wen W escreveu: 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. You should take a look at the videobuf2 for buffer management. It is flexible enough to be used on embedded hardware, as it splits the memory management on a separate module. In particular, the CMA allocator was designed to handle memory management on complex designs. You'll find extensive discussions about CMA and videobuf2 in the ML. The videobuf2 is already at linux-next and will be available for 2.6.39. Not sure about the status of the CMA allocator, as the patches are handled via another upstream tree. I hope that helps. Cheers, Mauro -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Memory allocation in Video4Linux
Penwell has IOMMU feature? As far as I know only part of Intel server processors have this feature which is designed originally for VT(virtualization technology). Wen, Can you refer to other ISP Soc drivers and see how they are dealing with this issue? I don't understand why you need to manage MMU inside ISP, I think the real problem is how can we allocate a large number of memory pages from IA side where ISP can access to by DMA. Any ISP document can be shared to help us understand what's the problem? -Bin -Original Message- From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Wang, Wen W Sent: Tuesday, February 08, 2011 11:27 PM To: Kanigeri, Hari K; Iyer, Sundar; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego-handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: Re: [Umg-meego-handset-kernel] Memory allocation in Video4Linux Hi Hari, You are right. What we need is virtual address. Currently we alloc pages (alloc_pages()) for any request. Store those pages for an image buffer into a list. We also manage the virtual address for ISP by ourself (the range from 0 to 4GB) and the page table for our MMU which is independent to system MMU page table. Thanks Wen -Original Message- From: Kanigeri, Hari K Sent: 2011年2月9日 15:22 To: Iyer, Sundar; Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego-handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: RE: Memory allocation in Video4Linux -Original Message- From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Iyer, Sundar Sent: Wednesday, February 09, 2011 12:20 PM To: Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego- handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: Re: [Umg-meego-handset-kernel] Memory allocation in Video4Linux 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. I believe CMA is for allocating physically contiguous memory and from what Wen mentioned he also needs virtual memory management, which the IOMMU will provide. Please check the open source discussion on CMA, the last I heard CMA proposal was shot down. Reference: http://www.spinics.net/lists/linux-media/msg26875.html Wen, how are you currently allocating physical memory ? Thank you, Best regards, Hari ___ Umg-meego-handset-kernel mailing list umg-meego-handset-ker...@umglistsvr.jf.intel.com http://umglistsvr.jf.intel.com/mailman/listinfo/umg-meego-handset-kernel
RE: Memory allocation in Video4Linux
-Original Message- From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Wang, Wen W Sent: Wednesday, February 09, 2011 11:53 AM To: linux-media@vger.kernel.org; umg-meego-handset- ker...@umglistsvr.jf.intel.com 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? Not sure if this meets your requirements, but check IOMMU driver. IOMMU driver is responsible to map the user buffers to Device's virtual address. Thank you, Best regards, Hari -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Wang, Wen W Sent: Wednesday, February 09, 2011 2:23 PM To: linux-media@vger.kernel.org; umg-meego-handset- ker...@umglistsvr.jf.intel.com 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-ker...@umglistsvr.jf.intel.com http://umglistsvr.jf.intel.com/mailman/listinfo/umg-meego-handset-kernel -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: 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@vger.kernel.org;
umg-meego-handset-ker...@umglistsvr.jf.intel.com
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-boun...@umglistsvr.jf.intel.com
[mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On
Behalf Of Wang, Wen W
Sent: Wednesday, February 09, 2011 2:23 PM
To: linux-media@vger.kernel.org; umg-meego-handset-
ker...@umglistsvr.jf.intel.com
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
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RE: Memory allocation in Video4Linux
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-boun...@umglistsvr.jf.intel.com [mailto:umg- meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Wang, Wen W Sent: Wednesday, February 09, 2011 12:03 PM To: Yang, Jianwei; linux-media@vger.kernel.org; umg-meego-handset- ker...@umglistsvr.jf.intel.com 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@vger.kernel.org; umg-meego-handset-ker...@umglistsvr.jf.intel.com 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-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Wang, Wen W Sent: Wednesday, February 09, 2011 2:23 PM To: linux-media@vger.kernel.org; umg-meego-handset- ker...@umglistsvr.jf.intel.com 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-ker...@umglistsvr.jf.intel.com http://umglistsvr.jf.intel.com/mailman/listinfo/umg-meego-handset-kernel ___ Umg-meego-handset-kernel mailing list umg-meego-handset-ker...@umglistsvr.jf.intel.com http://umglistsvr.jf.intel.com/mailman/listinfo/umg-meego-handset-kernel -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Memory allocation in Video4Linux
-Original Message- From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Iyer, Sundar Sent: Wednesday, February 09, 2011 12:20 PM To: Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego- handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: Re: [Umg-meego-handset-kernel] Memory allocation in Video4Linux 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. I believe CMA is for allocating physically contiguous memory and from what Wen mentioned he also needs virtual memory management, which the IOMMU will provide. Please check the open source discussion on CMA, the last I heard CMA proposal was shot down. Reference: http://www.spinics.net/lists/linux-media/msg26875.html Wen, how are you currently allocating physical memory ? Thank you, Best regards, Hari -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Memory allocation in Video4Linux
Hi Hari, You are right. What we need is virtual address. Currently we alloc pages (alloc_pages()) for any request. Store those pages for an image buffer into a list. We also manage the virtual address for ISP by ourself (the range from 0 to 4GB) and the page table for our MMU which is independent to system MMU page table. Thanks Wen -Original Message- From: Kanigeri, Hari K Sent: 2011年2月9日 15:22 To: Iyer, Sundar; Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego-handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: RE: Memory allocation in Video4Linux -Original Message- From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com [mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On Behalf Of Iyer, Sundar Sent: Wednesday, February 09, 2011 12:20 PM To: Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego- handset-ker...@umglistsvr.jf.intel.com Cc: Jozef Kruger Subject: Re: [Umg-meego-handset-kernel] Memory allocation in Video4Linux 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. I believe CMA is for allocating physically contiguous memory and from what Wen mentioned he also needs virtual memory management, which the IOMMU will provide. Please check the open source discussion on CMA, the last I heard CMA proposal was shot down. Reference: http://www.spinics.net/lists/linux-media/msg26875.html Wen, how are you currently allocating physical memory ? Thank you, Best regards, Hari
Re: Memory allocation in Video4Linux
On Wednesday, February 09, 2011 08:27:27 Wang, Wen W wrote:
Hi Hari,
You are right. What we need is virtual address.
Currently we alloc pages (alloc_pages()) for any request. Store those pages
for an image buffer into a list. We also manage the virtual address for ISP
by ourself (the range from 0 to 4GB) and the page table for our MMU which is
independent to system MMU page table.
Assuming you are using video4linux for this driver, then you should take a
look at the new videobuf2 framework that will appear in 2.6.39. It is already
in the media tree (http://git.linuxtv.org/media_tree.git, see
include/media/videobuf2-core.h).
It is much better than the old videobuf framework, and in particular gives
the driver much more control on how memory is allocated and used.
Regards,
Hans
Thanks
Wen
-Original Message-
From: Kanigeri, Hari K
Sent: 2011年2月9日 15:22
To: Iyer, Sundar; Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org;
umg-meego-handset-ker...@umglistsvr.jf.intel.com
Cc: Jozef Kruger
Subject: RE: Memory allocation in Video4Linux
-Original Message-
From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com
[mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On
Behalf Of Iyer, Sundar
Sent: Wednesday, February 09, 2011 12:20 PM
To: Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego-
handset-ker...@umglistsvr.jf.intel.com
Cc: Jozef Kruger
Subject: Re: [Umg-meego-handset-kernel] Memory allocation in
Video4Linux
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.
I believe CMA is for allocating physically contiguous memory and from what
Wen
mentioned he also needs virtual memory management, which the IOMMU will
provide. Please check the open source discussion on CMA, the last I heard CMA
proposal was shot down.
Reference: http://www.spinics.net/lists/linux-media/msg26875.html
Wen, how are you currently allocating physical memory ?
Thank you,
Best regards,
Hari
�翳�.n�+%��遍荻�w��.n��伐�{炳g����n�r■�ㄨ｛�夸z罐zf＂赙z_璁�:+v�)撸�
--
Hans Verkuil - video4linux developer - sponsored by Cisco
--
To unsubscribe from this list: send the line unsubscribe linux-media in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Memory allocation in Video4Linux
Hi Hans,
Thanks for your point and videobuf2 is also what I want to use.
But since our development kernel version right now is still 2.6.35, I need to
find way to work with current videobuf framework.
Thanks
Wen
-Original Message-
From: Hans Verkuil [mailto:hverk...@xs4all.nl]
Sent: 2011年2月9日 15:52
To: Wang, Wen W; Jozef Kruger
Cc: Kanigeri, Hari K; Iyer, Sundar; Yang, Jianwei; linux-media@vger.kernel.org
Subject: Re: Memory allocation in Video4Linux
On Wednesday, February 09, 2011 08:27:27 Wang, Wen W wrote:
Hi Hari,
You are right. What we need is virtual address.
Currently we alloc pages (alloc_pages()) for any request. Store those pages
for an
image buffer into a list. We also manage the virtual address for ISP by
ourself (the
range from 0 to 4GB) and the page table for our MMU which is independent to
system
MMU page table.
Assuming you are using video4linux for this driver, then you should take a
look at the new videobuf2 framework that will appear in 2.6.39. It is already
in the media tree (http://git.linuxtv.org/media_tree.git, see
include/media/videobuf2-core.h).
It is much better than the old videobuf framework, and in particular gives
the driver much more control on how memory is allocated and used.
Regards,
Hans
Thanks
Wen
-Original Message-
From: Kanigeri, Hari K
Sent: 2011年2月9日 15:22
To: Iyer, Sundar; Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org;
umg-meego-handset-ker...@umglistsvr.jf.intel.com
Cc: Jozef Kruger
Subject: RE: Memory allocation in Video4Linux
-Original Message-
From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com
[mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com] On
Behalf Of Iyer, Sundar
Sent: Wednesday, February 09, 2011 12:20 PM
To: Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org; umg-meego-
handset-ker...@umglistsvr.jf.intel.com
Cc: Jozef Kruger
Subject: Re: [Umg-meego-handset-kernel] Memory allocation in
Video4Linux
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.
I believe CMA is for allocating physically contiguous memory and from what
Wen
mentioned he also needs virtual memory management, which the IOMMU will
provide. Please check the open source discussion on CMA, the last I heard
CMA
proposal was shot down.
Reference: http://www.spinics.net/lists/linux-media/msg26875.html
Wen, how are you currently allocating physical memory ?
Thank you,
Best regards,
Hari
�翳�.n�+%��遍荻�w��.n��伐�{炳g����n�r■�ㄨ｛�
夸z罐zf＂赙z_璁�:+v�)撸�
--
Hans Verkuil - video4linux developer - sponsored by Cisco
RE: Memory allocation in Video4Linux
Hi,
Maybe VCM is helpful for you. Please refer to the following URL.
http://marc.info/?l=linux-mmm=129255940319217w=2
Best regards,
Jonghun Han
Wednesday, February 09, 2011 4:52 PM Hans Verkuil wrote:
-Original Message-
From: linux-media-ow...@vger.kernel.org [mailto:linux-media-
ow...@vger.kernel.org] On Behalf Of Hans Verkuil
Sent: Wednesday, February 09, 2011 4:52 PM
To: Wang, Wen W; Jozef Kruger
Cc: Kanigeri, Hari K; Iyer, Sundar; Yang, Jianwei; linux-media@vger.kernel.org
Subject: Re: Memory allocation in Video4Linux
On Wednesday, February 09, 2011 08:27:27 Wang, Wen W wrote:
Hi Hari,
You are right. What we need is virtual address.
Currently we alloc pages (alloc_pages()) for any request. Store those pages
for
an image buffer into a list. We also manage the virtual address for ISP by
ourself
(the range from 0 to 4GB) and the page table for our MMU which is independent
to
system MMU page table.
Assuming you are using video4linux for this driver, then you should take a
look at
the new videobuf2 framework that will appear in 2.6.39. It is already in the
media
tree (http://git.linuxtv.org/media_tree.git, see
include/media/videobuf2-core.h).
It is much better than the old videobuf framework, and in particular gives
the driver
much more control on how memory is allocated and used.
Regards,
Hans
Thanks
Wen
-Original Message-
From: Kanigeri, Hari K
Sent: 2011年2月9日 15:22
To: Iyer, Sundar; Wang, Wen W; Yang, Jianwei;
linux-media@vger.kernel.org;
umg-meego-handset-ker...@umglistsvr.jf.intel.com
Cc: Jozef Kruger
Subject: RE: Memory allocation in Video4Linux
-Original Message-
From: umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com
[mailto:umg-meego-handset-kernel-boun...@umglistsvr.jf.intel.com]
On Behalf Of Iyer, Sundar
Sent: Wednesday, February 09, 2011 12:20 PM
To: Wang, Wen W; Yang, Jianwei; linux-media@vger.kernel.org;
umg-meego- handset-ker...@umglistsvr.jf.intel.com
Cc: Jozef Kruger
Subject: Re: [Umg-meego-handset-kernel] Memory allocation in
Video4Linux
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.
I believe CMA is for allocating physically contiguous memory and from
what Wen mentioned he also needs virtual memory management, which the
IOMMU will provide. Please check the open source discussion on CMA,
the last I heard CMA proposal was shot down.
Reference: http://www.spinics.net/lists/linux-media/msg26875.html
Wen, how are you currently allocating physical memory ?
Thank you,
Best regards,
Hari
翳 .n +% 遍荻 w .n 伐 {炳g n r■ ㄨ｛ 夸z罐zf＂
赙z_璁 :+v )撸
--
Hans Verkuil - video4linux developer - sponsored by Cisco
--
To unsubscribe from this list: send the line unsubscribe linux-media in the
body
of a message to majord...@vger.kernel.org More majordomo info at
http://vger.kernel.org/majordomo-info.html
--
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the body of a message to majord...@vger.kernel.org
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