[PATCH] drm/i915/display: Don't program DBUF_CTL tracker state service

[Bhadane, Dnyaneshwar]

On 18-Dec-24 11:54 PM, Vodapalli, Ravi Kumar wrote:
> Hi,
> 
> My inline comments
> 
> 
> On 12/18/2024 2:07 AM, Bhadane, Dnyaneshwar wrote:
>>> -----Original Message-----
>>> From: Vodapalli, Ravi Kumar<ravi.kumar.vodapalli at intel.com>
>>> Sent: Tuesday, December 17, 2024 11:00 PM
>>> To:intel-gfx at lists.freedesktop.org
>>> Cc: Vivekanandan, Balasubramani
>>> <balasubramani.vivekanandan at intel.com>; Roper, Matthew D
>>> <matthew.d.roper at intel.com>; De Marchi, Lucas
>>> <lucas.demarchi at intel.com>; Sousa, Gustavo<gustavo.sousa at intel.com>;
>>> Taylor, Clinton A<clinton.a.taylor at intel.com>; Atwood, Matthew S
>>> <matthew.s.atwood at intel.com>; Bhadane, Dnyaneshwar
>>> <dnyaneshwar.bhadane at intel.com>; Kalvala, Haridhar
>>> <haridhar.kalvala at intel.com>; Chauhan, Shekhar
>>> <shekhar.chauhan at intel.com>
>>> Subject: [PATCH] drm/i915/display: Don't program DBUF_CTL tracker state
>>> service
>>>
>>> While display initialization along with MBUS credits programming DBUF_CTL
>>> register is also programmed, as a part of it the tracker state service field is
>>> also set to 0x8 value when default value is other than 0x8 which are for
>>> platforms past display version 13.
>>> For remaining platforms the default value is already 0x8 so don't program
>>> them.
>>>
>>> Bspec: 49213
>>> Signed-off-by: Ravi Kumar Vodapalli<ravi.kumar.vodapalli at intel.com>
>>> ---
>>>   drivers/gpu/drm/i915/display/intel_display_power.c | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c
>>> b/drivers/gpu/drm/i915/display/intel_display_power.c
>>> index 34465d56def0..cbcc4bddc01f 100644
>>> --- a/drivers/gpu/drm/i915/display/intel_display_power.c
>>> +++ b/drivers/gpu/drm/i915/display/intel_display_power.c
>>> @@ -1126,7 +1126,7 @@ static void gen12_dbuf_slices_config(struct
>>> intel_display *display)  {
>>>   	enum dbuf_slice slice;
>>>
>>> -	if (display->platform.alderlake_p)
>>> +	if (DISPLAY_VER(display) >= 13)
>> Hi Ravi,
>> This new condition is not needed here since there's already a similar check in the caller function icl_display_core_init().
>> Please update the condition at the caller function and remove this code from here.
> 
> As MattR explained The function gen12_dbuf_slices_config() name suggest 
> that it is called for gen12 platform onwards and higher, any changes in 
> the code for higher platforms has to be implemented in that function. 

I don't know which part of my review was unclear that you mixed it up 
with what you wrote above. But what I am trying to convey is that we can 
easily modify the caller function condition as

	if (DISPLAY_VER(display) == 12)

instead of modifying the platform check inside gen12_dbuf_slices_config()

Dnyaneshwar

> Ravi Kumar V
>> Dnyaneshwar,
>>>   		return;
>>>
>>>   	for_each_dbuf_slice(display, slice)
>>> --
>>> 2.25.1
>