From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Vasut <marek.vasut@gmail.com>
Date: Mon, 27 Feb 2012 14:14:26 +0100
Subject: [U-Boot] [PATCH] USB:host: Attribute packed removed from usb
	structures
In-Reply-To: <4F4B2DD7.10009@st.com>
References: <1330084720-16878-1-git-send-email-amit.virdi@st.com>
	<4F48B3FB.20200@aribaud.net> <4F4B2DD7.10009@st.com>
Message-ID: <201202271414.26549.marek.vasut@gmail.com>
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To: u-boot@lists.denx.de

> On 2/25/2012 3:42 PM, Albert ARIBAUD wrote:
> > Hi Amit,
> 
> Hello Albert,
> 
> > Le 24/02/2012 12:58, Amit Virdi a ?crit :
> >> From: Vipin Kumar<vipin.kumar@st.com>
> >> 
> >> Packed attribute is forcing a bytewise write on device registers,
> >> there by, resulting in a misbehavior on gcc-4.4.1.
> >> Reverting the structures to non-packed
> > 
> > If (just asking, not asserting) the issue is caused by fields being u8
> > where u8 access is not possible, then should you not make the fields u16
> > / u32 according to access requirements?
> 
> The problem is not with the fields being of a different width. AFAIK,
> the packed attribute changes the generated code to access even the word
> field elements in a byte by byte manner
> 
> Infact, there is a discussion on lkml that I can point
> https://lkml.org/lkml/2011/4/27/278
> 
> It seems that the discussion did not lead to a conclusion but it was
> sensible (at least for ARM) to remove the packed attribute from this
> structure
> 
What does the USB spec say ? It might be a HW bug?

M