From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vipin Kumar <vipin.kumar@st.com>
Date: Mon, 4 Oct 2010 15:08:29 +0530
Subject: [U-Boot] packed attribute problem
Message-ID: <4CA9A095.9000900@st.com>
List-Id: <u-boot.lists.denx.de>
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To: u-boot@lists.denx.de

Hi All,

I encountered a problem something like

struct xyz {
	int	x;
	int	y;
	int	z[CONST];
} __attribute__ ((packed));

struct xyz *abc;
u32 * status_reg = (u32 *)&abc->z[0];

writel(status, status_reg);

This writel results in writing byte by byte on the address pointed to by status_reg.
This problem is visible with both gcc version 4.4.1 as well as 4.5.0

Incidently, the same code works well with 4.2.4

The problem is visible in the usb host driver which uses the packed structures for 
accessing  device registers.

Regards
Vipin