Re: [PATCH 2/2] drm/tidss: Add support for AM62L display subsystem

[Devarsh Thakkar]

Hi Tomi

>> Thanks for pointing out, I probably missed this since the use-case still
>> worked since VP interrupts were still enabled and those were sufficient to
>> drive the display
>> but the VID underflow interrupts and VID specific bits were probably not
>> enabled at-all due to above miss, so agreed
>> we should probably go ahead with a different reg space for AM62L due to
>> aforementioned differences.
> 
> I think I disagree here. Afaiu, AM62L has plane at hw index 1 (VIDL1), but the
> plane at hw index 0 (VID1) is not instantiated in the hardware. But the
> registers are the same, i.e. AM62L's registers for VIDL1 match AM65x/AM62x
> registers, right?
> 
> If so, we just need to tell the driver the hw index, instead of creating new
> register offsets as done in v2.
> 
> Or am I missing something here? (I haven't looked at the HW manual yet).
> 

No that's not the only difference. For AM62L, the VID_IRQENABLE/STATUS
registers start at +0x4 as compared to AM65x/AM62x/ :

AM62L:
        [DISPC_VID_IRQENABLE_OFF] =             0x48,

        [DISPC_VID_IRQSTATUS_OFF] =             0x5c,

AM62x/AM65x:

        [DISPC_VID_IRQENABLE_OFF] =             0x44,

        [DISPC_VID_IRQSTATUS_OFF] =             0x58,

So it seems okay to me to have a separate reg offset struct.

Regards
Devarsh