[PATCH v2 1/9] of: Add NVIDIA Tegra XUSB mailbox binding

Andrew Bresticker abrestic at chromium.org
Wed Aug 27 09:33:59 PDT 2014


On Mon, Aug 25, 2014 at 11:48 AM, Stephen Warren <swarren at wwwdotorg.org> wrote:
> On 08/18/2014 11:08 AM, Andrew Bresticker wrote:
>
>> diff --git a/include/dt-bindings/mailbox/tegra-xusb-mailbox.h
>> b/include/dt-bindings/mailbox/tegra-xusb-mailbox.h
>
>
>> +#define TEGRA_XUSB_MBOX_CHAN_HOST      0
>> +#define TEGRA_XUSB_MBOX_CHAN_PHY       1
>
>
> I can't work out how these values relate to hardware at all. Are they in
> fact properties of the particular firmware that's loaded into the XUSB
> module? If so, I don't think the DT should contain these values at all.

Yes this is rather ugly... they're used by software for the demuxing
of messages and don't correspond to actual hardware.

> I wonder if the individual MBOX_CMD_* values from patch 2 are any
> better, although I think those are also defined by the firmware, not the
> hardware?

They are indeed defined by the firmware, so this would become an issue
if the firmware API ever changed.



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