Re: [ECOS] How to interpret hal_platform_extra.h?

[Gary Thomas <gary at mlbassoc dot com>]

On Wed, 2003-08-13 at 04:44, Jason Geng wrote:
> Hi all,
> I am working on a ixdp425 board which has 4 chips of 16M SDRAM, while
> the standdard release has 4chips of 64M. It seems that I have to modify
> the MMU table in hal_platform_extra.h to make it adapt to my board. But I
>  can't understand the following code:
> ======================
> //256MB SDRAM
> .set __base,0x000
> .rept 0x100 - 0x000
> FL_SECTION_ENTRY __base,0,3,0,0,1,0
> .set __base,__base+1
> .endr
> 
> //...some other similar sections
> =======================
> Could anyone please give me some advice on this?  Thank you.

This table entry is setting the MMU to map the 256MB from
0x00000000..0x0FFFFFFF.  

I think that all you should have to change are the SDRAM settings in 
hal/arm/xscale/ixdp425/current/include/ixdp425.h:
  #define SDRAM_SIZE                         0x10000000  // 256MB
  #define IXP425_SDRAM_CONFIG_INIT  (SDRAM_CONFIG_CAS_3 | SDRAM_CONFIG_4x32Mx16)

My guess:
  #define SDRAM_SIZE                         0x04000000  // 64MB
  #define IXP425_SDRAM_CONFIG_INIT  (SDRAM_CONFIG_CAS_3 | SDRAM_CONFIG_4x8Mx16)

Change these to match your hardware and it should work fine.
-- 
Gary Thomas <gary@mlbassoc.com>
MLB Associates


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