Re: [PATCH v01 2/3] xen/arm: add platform specific definitions for DRA7 evm board

[Julien Grall <julien.grall@linaro.org>]

Hi Ian,

On 27/06/14 13:17, Ian Campbell wrote:
>> +    /* OMAP Linux kernel handles devices with status "disabled" in a
>> +     * weird manner - tries to reset them. While their memory ranges
>> +     * are not mapped, this leads to data aborts, so skip these devices
>> +     * from DT for dom0.
>> +     */
>> +    DT_MATCH_NOT_AVAILABLE(),
>
> I think this should be done in common code, either by default (if that
> makes sense) or using a new quirk flag.

Both of these solutions doesn't make sense to me. A device which is not 
available should not be touch by the kernel. In most of the case, Linux 
ignores a device which is not available (see amba/platform register code).

For instance, some board has the same SOC but with different devices 
enabled/disabled. In this case, there is usually a common device tree 
with all enabled/disabled, and a specific device tree which override 
some properties.

If OMAP does weird thinks with the device tree, then we should keep it 
in the platform code.

Regards,

-- 
Julien Grall