clk: mxs: Invalid register access on HW_CLKCTRL_FRAC0?

Uwe Kleine-König u.kleine-koenig at
Sat Dec 13 12:36:16 PST 2014

On Sat, Dec 13, 2014 at 01:23:29PM +0100, Stefan Wahren wrote:
> Hi Fabio,
> yesterday i stumble on this note in the i.MX28 reference manual (p. 931):
(when talking page numbers it's usually helpful to also specify the
document more exactly. I use "i.MX28 Applications Processor Reference
Manual Rev2, 08/2013", the page number seems to match.)

>     10.8.24 Fractional Clock Control Register 0 (HW_CLKCTRL_FRAC0)
>     NOTE: This register can only be addressed by byte instructions. Addressing
> word or half-word are not allowed.
> The same applies to HW_CLKCTRL_FRAC1.
Bah, looking at the example code for this register:

	*((u8 *)(HW_CLKCTRL_FRAC0_ADDR + 1)) = 30;

without any further comment.  The documentation writes could at least
have added:

	Assuming little endian operation this command sets EMIFRAC=0x1e

Best regards

Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 |  |

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