[ECOS] Getting Configuration information from FLASH

[ECOS] Getting Configuration information from FLASH

[Paul Fine]

I recently ran into a problem getting configuration information stored in 
FLASH into my application. After tracking the problem down, it appears 
that, while the Virtual Vector lookup is correctly getting to the 
flash_get_config() function, the region in memory where RedBoot had stashed 
the copy of the configuration structure had been overwritten in the startup 
process of my eCos application.

I solved the problem by adding some code to flash_get_config() which, after 
the call to flash_lookup_config() returns false, checks to see if the 
configuration structure is still valid. If not valid, the pointer to the 
configuration structure is set to point to the read only copy in FLASH, and 
checks again to see if it is valid.  If it is valid, then I will call 
flash_get_config and get my configuration item.

Has anyone else had this problem using this virtual vector call?  Unless I 
hear otherwise, I will submit the patch after I have tested it some more.


Paul Fine
Senior Member of Technical Staff
Delphi Communication Systems, Inc.


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Re: [ECOS] Getting Configuration information from FLASH

[Jonathan Larmour]

Paul Fine wrote:
> 
> I recently ran into a problem getting configuration information stored in
> FLASH into my application. After tracking the problem down, it appears
> that, while the Virtual Vector lookup is correctly getting to the
> flash_get_config() function, the region in memory where RedBoot had stashed
> the copy of the configuration structure had been overwritten in the startup
> process of my eCos application.
> 
> I solved the problem by adding some code to flash_get_config() which, after
> the call to flash_lookup_config() returns false, checks to see if the
> configuration structure is still valid. If not valid, the pointer to the
> configuration structure is set to point to the read only copy in FLASH, and
> checks again to see if it is valid.  If it is valid, then I will call
> flash_get_config and get my configuration item.
> 
> Has anyone else had this problem using this virtual vector call?  Unless I
> hear otherwise, I will submit the patch after I have tested it some more.

Actually I believe we came across it ourselves, or something very similar
in some other VV call. It does sound like your patch would be reasonable.

Jifl
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