[Intel-gfx] [RFC] drm/i915: make dev_priv usage explitic in some macros

[Lucas De Marchi]

On Wed, Feb 01, 2023 at 07:09:12PM +0200, Jani Nikula wrote:
>On Wed, 01 Feb 2023, Luca Coelho <luciano.coelho at intel.com> wrote:
>> There are a few macros (e.g. DPLL()) that implicitly use dev_priv, by
>> using other macros that implcitily use dev_priv.
>>
>> In an effort to align all definitions of struct drm_i915_private to be
>> declared as i915 instead of arbitrarily using either i915 or dev_priv,
>> we need to make these macros explicitly use dev_priv, so that we can
>> change them later to be defined as i915.
>
>Lucas posted a slightly related patch [1], and I think based on the
>discussion we should probably add AUX and DPLL registers that are
>VLV/CHV specific, and include the MMIO offset directly without dev_priv,
>and non-VLV/CHV macros that will have MMIO offset 0. This would reduce
>the implicit dev_priv considerably, and avoid the need to pass i915
>pointer to those register macros altogether.
>
>> diff --git a/drivers/gpu/drm/i915/display/vlv_dsi_regs.h b/drivers/gpu/drm/i915/display/vlv_dsi_regs.h
>> index abbe427e462e..d00e9321064a 100644
>> --- a/drivers/gpu/drm/i915/display/vlv_dsi_regs.h
>> +++ b/drivers/gpu/drm/i915/display/vlv_dsi_regs.h
>> @@ -100,7 +100,7 @@
>>
>>  #define _MIPIA_DEVICE_READY		(_MIPI_MMIO_BASE(dev_priv) + 0xb000)
>>  #define _MIPIC_DEVICE_READY		(_MIPI_MMIO_BASE(dev_priv) + 0xb800)
>> -#define MIPI_DEVICE_READY(port)		_MMIO_MIPI(port, _MIPIA_DEVICE_READY, _MIPIC_DEVICE_READY)
>> +#define MIPI_DEVICE_READY(dev_priv, port) _MMIO_MIPI(port, _MIPIA_DEVICE_READY, _MIPIC_DEVICE_READY)
>
>While this kind of passes dev_priv as parameter, the dev_priv in
>_MIPIA_DEVICE_READY and _MIPIC_DEVICE_READY is still implicit. I think
>these could use a similar treatment as in [1], moving the
>_MIPI_MMIO_BASE() part one level up.

Agreed.  I think we should have these manual changes first: they make the
interface better and can even be merged  without churn to the codebase,
as they are header-only.

Then the rest we mass convert with a script like shared here.

Lucas De Marchi