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Hi,

Hi Rich,
Thanks for your inputs. Well, I have already looked into the section that you have mentioned. I tried to use the frame-pointer, stack-pointer related info given there to trace the arguments. But I did not get any success. I figured out that once you say something like : <printf("A = %d",a_value);> , the 'a_value' first gets stored in GPR R3. You can see this in the GPR dump created by or1200_monitor.v. However, when the actual call to the printf in support.c happens, the R3 gets overwritten. After that, I do not have a clue as to where does the argument 'a_value' go. That’s where I am stuck as of now.
Thanks,
Rahul.
-----Original Message-----
From: openrisc-bounces@o... [mailto:openrisc-bounces@o...] On Behalf Of rich_daddio@y...
Sent: 22 फरवरी 2008 05:01
To: openrisc@o...
Subject: Re: [openrisc] Printf using OR1K C test and verilog.

Hi,
I am not sure if this is what you are looking for but take a look at
OpenRISC 1000 Architecture Manual under "Function Calling Sequence"
and the table of registers, and that might help you.

http://www.opencores.org/cvsweb.shtml/or1k/docs/openrisc_arch.pdf

HTH & Best Regards,

Rich d
----- Original Message ----- 
From: Rahul Wagh<rahul.wagh@m...> 
To: 
Date: Wed Feb 20 09:14:25 CET 2008 
Subject: [openrisc] Printf using OR1K C test and verilog. 

> Hi, 
> 
> As you might have seen, when we say printf("....") in a 
> OR1k testcase 
> written in C, it calls the printf routine written in support.c 
> file. That 
> does not give the actual printing of the message within 
> "..." though. 
> Anybody has tried that in OR1k ? Any suggestions / pointers ? 
> At my end, I figured out that the GPR R3 gets the starting address 
> of the 
> memory location where the message in printf is stored. Using that, 
> I wrote a 
> small code in verilog monitor (or1200_monitor.v) to access the 
> memory (till 
> you get an ASCII equivalent of NULL or something like that) and 
> display the 
> things in %c format to get the message. However, this helps only 
> for 
> 'pure-text' type messages. It does not work for messages like the 
> following 
> : 
> printf("Register value = %x",reg_value); 
> Can anybody throw some light on how to do this ? (How does one 
> track the 
> location of the arguments passed to the printf statement ? etc..) 
> Thanks, 
> Rahul. 
> 
> 
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