dspgateway-devel

[Dspgateway-devel] Regarding the use of external memory

[<vik...@wi...>]

Hi Everybody,
   I'm using dsp-gateway 2.01 version on linux-2.4.21 kernel.   My
application requires huge static buffers, which I plan to place in
External Memory. As I understand, I need to create an external memory
segment( in CCS' cdb file(say, at 0x260000)). Place my buffer in that
segment. Then on the arm side, before I load my program, I need to map
0x260000 to some valid memory using dspctl. Now, is the order right? Is
there a better, easier way of achieving it?
=20
Note: Application is not dynamically loaded.
=20
Thanks,
=20
Vikram.

Re: [Dspgateway-devel] Regarding the use of external memory

[<tos...@no...>]

Hi Vikram,

>    I'm using dsp-gateway 2.01 version on linux-2.4.21 kernel.   My
> application requires huge static buffers, which I plan to place in
> External Memory. As I understand, I need to create an external memory
> segment( in CCS' cdb file(say, at 0x260000)). Place my buffer in that
> segment. Then on the arm side, before I load my program, I need to map
> 0x260000 to some valid memory using dspctl. Now, is the order right? Is
> there a better, easier way of achieving it?

Yes, your procedure is correct.
Before loading your program, you need to issue a dspctl exmap command.

Using the dynamic loader, the mapping step can be done automatically
(even if you don't use dynamic task),
but unfortunately the dynamic loader hasn't been released for
version 2.0.1. ;)

BR,
Toshihiro Kobayashi