2009-03-30 16:31:11     Using bfin_read_MMR

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2009-03-30 16:31:11     Using bfin_read_MMR

Christopher Harrsen (UNITED STATES)

Message: 71793   

 

Hello,

 

I am trying to use bfin_read_MMR in a user application. Specifically bfin_read_PORTG_FER(). When I compile my code I get the following error.

 

/tmp/ccqZQhm5.o: In function `_main':

BF548_blink.c:(.text+0xd8): undefined reference to `_bfin_read_PORTG_FER'

collect2: ld returned 1 exit status

 

 

I included blackfin.h from asm-blackfin/mach-bf548/. Is there something else I should do?

 

Thanks

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2009-03-30 16:40:09     Re: Using bfin_read_MMR

Mike Frysinger (UNITED STATES)

Message: 71795   

 

uhh, MMRs are restricted to supervisor, so you cant access them from user space ...

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2009-03-30 17:22:04     Re: Using bfin_read_MMR

Christopher Harrsen (UNITED STATES)

Message: 71797   

 

Got it. I mis-interpreted the documentation.

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2009-03-30 17:56:53     Re: Using bfin_read_MMR

Mike Frysinger (UNITED STATES)

Message: 71799   

 

if you just want stuff for debugging purposes, use debugfs

 

docs.blackfin.uclinux.org/doku.php?id=linux-kernel:debug

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