On Tue, May 26, 2009 at 8:53 PM, Timur Tabi [off-list ref] wrote:

On Tue, May 26, 2009 at 7:44 PM, Jon Smirl [off-list ref] wrote:

quoted

Because Grant didn't want me doing udelay(50) just to delay things in
order to give the AC97 controller time to initialize. Your function
lets me loop on cpu_relax() for 50us.

But udelay() calls HMT_low(), which is like cpu_relax().

Then why did you need to make your routine that calls cpu_relax()?

I don't know what goes on in the guts of HMT_low() and cpu_relax(),
when you guys decide which one I should use let me know and I can
adjust the patch.

The hardware needs a minimum 50us pause. It doesn't matter if the
pause is more than that. If the CPU has something to keep it busy for
a few milliseconds that's fine.

--
Timur Tabi
Linux kernel developer at Freescale

-- 
Jon Smirl
jonsmirl@gmail.com