[PATCH 2/2] drm/i915/display: Print PICA version

[Lucas De Marchi]

On Fri, Dec 08, 2023 at 10:02:53AM -0800, Matt Roper wrote:
>On Fri, Dec 08, 2023 at 06:31:37AM -0800, Lucas De Marchi wrote:
>> The PICA_DEVICE_ID follows the same format as other GMD_ID registers
>> (graphics, display and media). Currently the only use for it is
>> informational for developers while checking the differences between
>> machines with the same platform. Print the raw number as there's no need
>> for the driver to check any of the fields.
>>
>> In future this may change, but then the IP version in
>> struct intel_display_runtime_info will need some refactor to allow
>> keeping both the display engine and PICA versions.
>>
>> Lastly, keeping the PICA version around in the display runtime info
>> matches its current use. If that changes in future, then it may need
>> to be moved to the device info.
>>
>> Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/intel_display_device.c | 5 +++++
>>  drivers/gpu/drm/i915/display/intel_display_device.h | 2 ++
>>  drivers/gpu/drm/i915/i915_reg.h                     | 2 ++
>>  3 files changed, 9 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_display_device.c b/drivers/gpu/drm/i915/display/intel_display_device.c
>> index 5d1084a98b93..d9d1be008e4c 100644
>> --- a/drivers/gpu/drm/i915/display/intel_display_device.c
>> +++ b/drivers/gpu/drm/i915/display/intel_display_device.c
>> @@ -956,6 +956,9 @@ static void __intel_display_device_info_runtime_init(struct drm_i915_private *i9
>>  	BUILD_BUG_ON(BITS_PER_TYPE(display_runtime->cpu_transcoder_mask) < I915_MAX_TRANSCODERS);
>>  	BUILD_BUG_ON(BITS_PER_TYPE(display_runtime->port_mask) < I915_MAX_PORTS);
>>
>> +	if (HAS_GMD_ID(i915))
>> +		display_runtime->pica_id = intel_de_read(i915, PICA_DEVICE_ID);
>> +
>>  	/* This covers both ULT and ULX */
>>  	if (IS_HASWELL_ULT(i915) || IS_BROADWELL_ULT(i915))
>>  		display_runtime->port_mask &= ~BIT(PORT_D);
>> @@ -1124,6 +1127,8 @@ void intel_display_device_info_print(const struct intel_display_device_info *inf
>>  {
>>  	drm_printf(p, "display version: %u.%02u.%02u\n",
>>  		   runtime->ip.ver, runtime->ip.rel, runtime->ip.step);
>> +	if (runtime->pica_id)
>> +		drm_printf(p, "PICA version: %#08x\n", runtime->pica_id);
>
>The actual, expected PICA version number on most (all?) MTL devices will
>be 0.0.  Should we make the condition here HAS_GMD_ID(i915) instead so
>that we print the value whenever we read it?  That will also help us
>notice if the PICA register is incorrectly 0 on LNL or later platforms
>where it should have been non-zero.

it seems intel_display_device_info_print() was specially crafted so we
don't have the i915/xe pointer and instead only operate on the info.
Yeah, we can get back to i915/xe, but I'm not sure about doing that.

What if we initialize it with U32_MAX and check for it here. I think it
would take a long time before that becomes invalid.

Another option is not to bother with the additional message in platforms
without it, and just print it unconditionally, like patch 1 does for the
rel/step.

Thoughts?

Lucas De Marchi

>
>
>Matt
>
>>
>>  #define PRINT_FLAG(name) drm_printf(p, "%s: %s\n", #name, str_yes_no(info->name))
>>  	DEV_INFO_DISPLAY_FOR_EACH_FLAG(PRINT_FLAG);
>> diff --git a/drivers/gpu/drm/i915/display/intel_display_device.h b/drivers/gpu/drm/i915/display/intel_display_device.h
>> index 79e9f1c3e241..f8a2ada1a4ec 100644
>> --- a/drivers/gpu/drm/i915/display/intel_display_device.h
>> +++ b/drivers/gpu/drm/i915/display/intel_display_device.h
>> @@ -123,6 +123,8 @@ struct intel_display_runtime_info {
>>
>>  	u8 fbc_mask;
>>
>> +	u32 pica_id;
>> +
>>  	bool has_hdcp;
>>  	bool has_dmc;
>>  	bool has_dsc;
>> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
>> index 27dc903f0553..9d70635508ae 100644
>> --- a/drivers/gpu/drm/i915/i915_reg.h
>> +++ b/drivers/gpu/drm/i915/i915_reg.h
>> @@ -6362,6 +6362,8 @@ enum skl_power_gate {
>>  #define  TCSS_DDI_STATUS_HPD_LIVE_STATUS_TBT	REG_BIT(1)
>>  #define  TCSS_DDI_STATUS_HPD_LIVE_STATUS_ALT	REG_BIT(0)
>>
>> +#define PICA_DEVICE_ID				_MMIO(0x16fe00)
>> +
>>  #define PRIMARY_SPI_TRIGGER			_MMIO(0x102040)
>>  #define PRIMARY_SPI_ADDRESS			_MMIO(0x102080)
>>  #define PRIMARY_SPI_REGIONID			_MMIO(0x102084)
>> --
>> 2.40.1
>>
>
>-- 
>Matt Roper
>Graphics Software Engineer
>Linux GPU Platform Enablement
>Intel Corporation