"ARM: MX3: fix CPU revision number detection" breaks QONG support

Andy Green andy at warmcat.com
Mon Dec 14 09:10:26 EST 2009

On 12/14/09 13:57, Somebody in the thread at some point said:

Hi Wolfgang -

> In Linux, the kernel hangs here:
> 	/* read SREV register from IIM module */
> 	srev = __raw_readl(IO_ADDRESS(IIM_BASE_ADDR) + MXC_IIMSREV);

In iMX31 IIM is very strangely a specifically 8-bit peripheral on a 
32-bit bus.  I wrote some code to read and write the fuses recently.

Maybe it's required to change it to __raw_readb; mine are already byte 

> In U-Boot, I can read this register just fine:
> 	=>  md 5001c024 1
> 	5001c024: 00000028    (...
> In Linux, the IO_ADDRESS() makes this a read from 0xFC11C024, which
> hangs.
> So if this is a clock thing, then it must be a clock being disabled by
> Linux.

Around my (working) IIM operations I have this code:

	iim_clk = clk_get(NULL, "iim");
	if (IS_ERR(iim_clk)) {
		pr_err("No IIM clock defined\n");
		return -EINVAL;




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