Re: [PATCH v5 21/22] xen/arm: ITS: Generate ITS node for Dom0

[Julien Grall <julien.grall@citrix.com>]

Hi Vijay,

On 26/08/2015 05:40, Vijay Kilari wrote:
>>> +        {
>>> +            fdt32_t phandle = gic_get_msi_handle();
>>> +            DPRINT(" Set msi-parent(ITS) phandle 0x%x\n",phandle);
>>> +            fdt_property(kinfo->fdt, prop->name, (void *)&phandle,
>>> +                         sizeof(phandle));
>>> +            continue;
>>> +        }
>>> +
>>>            res = fdt_property(kinfo->fdt, prop->name, prop_data, prop_len);
>>>
>>>            xfree(new_data);
>>> @@ -875,6 +888,10 @@ static int make_gic_node(const struct domain *d, void
>>> *fdt,
>>>            return res;
>>>
>>>        res = fdt_end_node(fdt);
>>> +    if ( res )
>>> +        return res;
>>> +
>>> +    res = gic_its_hwdom_dt_node(d, node, fdt);
>>
>>
>> Can you explain why you didn't follow my suggestion to plumb the ITS node
>> creation in gic_hwdow_dt_node? IHMO there is no need of new callback.
>>
>> Furthermore the call is misplaced. You will end up to have a DT looking like
>>
>> gic {
>> }
>>
>> gic-its {
>> }
>>
>> rather than
>>
>> gic {
>>    gic-its {
>>    }
>> }
>
>   As discussed, I have tried to generate ITS node inside gic node and call
> fdt_end_node() for gic after generating ITS node. But dom0 fails to
> find ITS node in the generated device tree. Any clue?

I can't give any clue without any log from Linux or code you've written...

I still think that your previous code is wrong (see 
Documentation/devicetree/bindings/arm/gic-v3.txt in Linux tree), because 
fdt_end_node of the parent should be called after all the children has 
been created i.e

fdt_begin_node(fdt, "gic");

/* properties of the gic node */

fdt_begin_node(fdt, "ITS");

/* properties of the ITS node */

fdt_end_node(fdt); // End of ITS
fdt_end_node(fdt); // End of GIC

Note that *all* the properties of the GIC node should have been written 
before creating the children nodes. Otherwise the device tree is 
considered as invalid.

Regards,

-- 
Julien Grall