From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
Subject: Re: [PATCH ARM v8 2/4] mini-os: arm: interrupt
	controller
Date: Wed, 22 Oct 2014 15:14:49 +0200
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To: Julien Grall <julien.grall@linaro.org>
Cc: Thomas Leonard <talex5@gmail.com>, Dave.Scott@eu.citrix.com, anil@recoil.org, stefano.stabellini@eu.citrix.com, xen-devel@lists.xenproject.org, Ian Campbell <Ian.Campbell@citrix.com>
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Julien Grall, le Wed 22 Oct 2014 14:06:44 +0100, a =E9crit :
> >>>> +    return value;
> >>>> +}
> >>>> +
> >>>> +static inline void REG_WRITE32(volatile uint32_t *addr, unsigned in=
t value)
> >>>> +{
> >>>> +    __asm__ __volatile__("str %0, [%1]"::"r"(value), "r"(addr));
> >>>> +    wmb();
> >>>> +}
> =

> write barrier may be necessary on some, where we need to wait that all
> write has been done before doing this one (such as enable the GIC ...).
> =

> So this function is buggy. It should be:
> =

> wmb();
> __asm__ __volatile__(....).

Well, I'd say it's the caller of REG_WRITE32 which should explicit it.

Samuel