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Date: Fri, 28 Sep 2007 15:26:51 -0500
From: Josh Boyer <jwboyer@linux.vnet.ibm.com>
To: "Grant Likely" <grant.likely@secretlab.ca>
Subject: Re: [PATCH 01/18] Virtex: Add uartlite bootwrapper driver
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Cc: linuxppc-dev@ozlabs.org, Arnd Bergmann <arnd@arndb.de>
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On Fri, 28 Sep 2007 14:04:04 -0600
"Grant Likely" <grant.likely@secretlab.ca> wrote:

> On 9/28/07, Arnd Bergmann <arnd@arndb.de> wrote:
> > On Friday 28 September 2007, Grant Likely wrote:
> > > +static void uartlite_putc(unsigned char c)
> > > +{
> > > +while ((in_be32(reg_base + 0x8) & 0x08) != 0); /* spin */
> > > +out_be32(reg_base + 0x4, c);
> > > +}
> >
> > When coding a spin-loop, it's better to do a cpu_relax() between
> > each attempt.
> 
> Is cpu_relax even implemented in the bootwrapper?

No.  And it doesn't need to be :)

josh