2008-12-18 08:38:41     PPI dma slower in 2008R1

Document created by Aaronwu Employee on Aug 13, 2013
Version 1Show Document
  • View in full screen mode

2008-12-18 08:38:41     PPI dma slower in 2008R1

supriya d (INDIA)

Message: 66858   

 

Hi All,

 

We are working with BF561 reference board.

 

We are porting our application consisting of Vidoe and audio on to 2008R1. This application was workign fine on 2007R1.

 

after completing the porting excersise we have seen that the PPI DMA's are taking longer time to complete than expected in 2008R1. Because of which we are seeing vertical jump in the video display. In this regard we had few queries,

 

1. are there any addtional DMAs used in 2008R1 as compared to 2007R1?

 

2. are there any additionaly chip naomalies taken into consideration in 2008R1 as compared to 2007R1 which can manifest in such a condition.

 

3. also, has anyone seen the issue of DMAs getting slower in 2008R1?

 

Any help in this regard is welcome. We are preparing for a urgent demo and this is a major blocking issue!!!

 

Please help.

 

TIA

 

 

QuoteReplyEditDelete

 

 

2008-12-18 08:55:09     Re: PPI dma slower in 2008R1

Michael Hennerich (GERMANY)

Message: 66860   

 

Can you explain "taking longer to complete" ?

 

I know in 2007R1 all DMA API functions used:

 

assert(dma_ch[channel].chan_status != DMA_CHANNEL_FREE

&& channel < MAX_BLACKFIN_DMA_CHANNEL);

 

default OFF

 

#define assert(expr) do {} while(0)

 

...

 

in 2008R1 we used BUG_ON()

 

default ON !!!

 

Can you try to remove those debug checks?

 

In our next release these have been removed and almost all DMA API functions are now declared as inline.

 

In addition there are various other DMA optimizations

 

 

 

-Michael

 

 

QuoteReplyEditDelete

 

 

2008-12-24 07:14:04     Re: PPI dma slower in 2008R1

supriya d (INDIA)

Message: 67091   

 

Hi Michael,

 

We have tried to remove the debug checks but we still see that the we wait longer for the DAM to complete.

 

 

 

Please suggest if this release is already made and if yes where can we get these files.

QuoteReplyEditDelete

 

 

2008-12-25 20:35:09     Re: PPI dma slower in 2008R1

Robin Getz (UNITED STATES)

Message: 67102   

 

Supriya:

 

The release has not been made yet.

 

Try trunk:

 

http://docs.blackfin.uclinux.org/doku.php?id=developing_with_blackfin_live_sources

 

-Robin

QuoteReplyEditDelete

 

 

2009-02-10 09:15:04     Re: PPI dma slower in 2008R1

supriya d (INDIA)

Message: 69201   

 

Hi,

 

I have 2 more questions in this regard,

 

1. Can you please suggest if this fix is made in 2008R1.5 or 2009 pre

 

2. Also a general query on whether the files/modifications as part of 2008R1 trunk/svn being taken to 2008R1.5

 

TIA.

 

Supriya.

 

 

QuoteReplyEditDelete

 

 

2009-02-10 09:34:23     Re: PPI dma slower in 2008R1

Michael Hennerich (GERMANY)

Message: 69203   

 

>Submitted By: supriya d (supriya)

>1. Can you please suggest if this fix is made in 2008R1.5 or 2009 pre

 

We enhanced the DMA driver for our 2009R1 release (current svn/trunk).

Most of the DMA API functions are now declared inline, and the error checking has been removed.

 

>2. Also a general query on whether the files/modifications as part of

>2008R1 trunk/svn being taken to 2008R1.5

 

We typically only check bug fixes into our release branches in svn.

Performance optimizations on svn/trunk are not back-ported into the release branches.

 

Does this answer your questions?

 

-Michael

 

QuoteReplyEditDelete

 

 

2009-02-12 06:51:36     Re: PPI dma slower in 2008R1

supriya d (INDIA)

Message: 69342   

 

Hi,

 

Thanks for the info. Also wanted to check when is the offcial 2009R1 release expected to be released.

 

TIA

 

Supriya

 

 

QuoteReplyEditDelete

 

 

2009-02-12 07:45:08     Re: PPI dma slower in 2008R1

Robin Getz (UNITED STATES)

Message: 69343   

 

2009 should be avalible around April/May ish.

 

-Robin

Attachments

    Outcomes