[U-Boot] [PATCH] arm: Kirkwood: Add memory barriers to kwgbe_send/recv

[Detlev Zundel]

Hi Simon,

> Add memory barriers to kwgbe_send/recv
>
> kwgbe_send/recv both have loops waiting for the hardware to set  a bit.
> GCC 4.3.3 cleverly optimizes this to ... a while(1); loop. This patch
> introduces memory barriers to force re-loading of the transmit descriptor.
>
> mb() wasn't defined for arm, but perhaps it should?

You should rather use read/write accessor macros which "do the right
thing".  Try using readl() for the loop.  Memory barriers do not belong
into "upper level" code.

Cheers
  Detlev

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