[U-Boot] packed attribute problem

[Wolfgang Denk]

Dear Vipin Kumar,

In message <4CA9A095.9000900 at st.com> you wrote:
> 
> 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

I bet this is on some ARM system?

> Incidently, the same code works well with 4.2.4

...which surprises me. I thought this has always been an ARM
"feature".

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

Hm... Why do these structs have any "__attribute__ ((packed))" at all?

Best regards,

Wolfgang Denk

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