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Re: [Xen-devel] [PATCH 3/12] VTPM mini-os: Add ioread() and iowrite() fu

To: Matthew Fioravante <matthew.fioravante@xxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH 3/12] VTPM mini-os: Add ioread() and iowrite() functions to mini-os
From: Samuel Thibault <samuel.thibault@xxxxxxxxxxxx>
Date: Sat, 12 Mar 2011 01:29:14 +0100
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Matthew Fioravante, le Fri 11 Mar 2011 17:38:32 -0500, a écrit :
> Mini-os currently doesn't have very many facilities for reading and 
> writing to hardware io memory. This patch addes  a new header file 
> iorw.h which when included gives access to
> the ioread8(), iread32(), iowrite8(), iowrite32() family of functions. 


> +void iowrite8(void* addr, uint8_t val)
> +{
> +   *((uint8_t*)addr) = val;
> +}
> +void iowrite32(void* addr, uint32_t val)
> +{
> +   *((uint32_t*)addr) = val;
> +}

Don't you need a volatile qualifier on the cast pointer to not let the
compiler optimize it away?

Samuel

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