From: Wolfgang Denk <wd@denx.de>
Date: Mon, 05 Nov 2007 20:21:58 +0100
Subject: [U-Boot-Users] Spartan FPGA patch
In-Reply-To: Your message of "Mon, 05 Nov 2007 14:58:59 +0200."
	<472F1393.7040306@inaccessnetworks.com>
Message-ID: <20071105192158.E9101247F4@gemini.denx.de>
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In message <472F1393.7040306@inaccessnetworks.com> you wrote:
> Wolfgang Denk wrote:
> > In message <472752F9.9000307@inaccessnetworks.com> you wrote:
> >> The following patch fixes a bug in the slave serial programming mode for 
> >> the xilinx spartan2 FPGA. A "char val" is declared, but it is used as a 
> >> signed char. The check for negative value (<0) is always true on arm, or 
> >> any other platform in which the char is not signed by default. As a 
> >> result the FPGA cannot be programmed.
> > 
> > I have to admit that I hate to see "signed  char"  in  the  code.  Is
> > there  any  special  reaso why "val" has to be a "char" type? Why not
> > making it an "int" ?
> 
> Another way to do this safely is to declare it as an "unsigned char" and 
> instead of doing "val < 0", do "val & 0x80". I don't like the current 
> code either. Shifting a signed char and testing for negativity is 
> definitely not the best way to test that the MSB is set.

So let me repeat my question: is there any special reason  why  "val"
has to be a "char" type? Why not making it an "int" ?


Best regards,

Wolfgang Denk

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DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
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