Re: [Intel-gfx] [PATCH 1/1] drm/i915/uc: Update to latest GuC and use new-format GuC/HuC names

[Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>]

On 15/09/2022 21:03, John Harrison wrote:
> On 9/15/2022 01:59, Tvrtko Ursulin wrote:
>>
>> Hi,
>>
>> On 15/09/2022 00:46, John.C.Harrison@Intel.com wrote:
>>> From: John Harrison <John.C.Harrison@Intel.com>
>>>
>>> Going forwards, the intention is for GuC firmware files to be named
>>> for their major version only and HuC firmware files to have no version
>>> number in the name at all. This patch adds those entries for all
>>> platforms that are officially GuC/HuC enabled.
>>>
>>> Also, update the expected GuC version numbers to the latest firmware
>>> release for those platforms.
>>>
>>> Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
>>> ---
>>>   drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c | 10 +++++++---
>>>   1 file changed, 7 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c 
>>> b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
>>> index 1169e2a09da24..b91ad4aede1f7 100644
>>> --- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
>>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
>>> @@ -72,12 +72,14 @@ void intel_uc_fw_change_status(struct intel_uc_fw 
>>> *uc_fw,
>>>    * security fixes, etc. to be enabled.
>>>    */
>>>   #define INTEL_GUC_FIRMWARE_DEFS(fw_def, guc_maj, guc_mmp) \
>>> -    fw_def(DG2,          0, guc_mmp(dg2,  70, 4, 1)) \
>>> +    fw_def(DG2,          0, guc_maj(dg2,  70, 5)) \
>>
>> Just glancing over out of curiosity. Part which confused me is that if 
>> only major is supposed to be used then what is the '5' in guc_maj(dg2, 
>> 70, 5) ?
> See the earlier patch that added support for version reduced filenames. 
> The minor number is still specified because want to be able to warn the 
> user if their firmware is out of date and causing them to miss features, 
> security fixes, etc. The driver will still load any old firmware with 
> the right name and work with it, but user's need to know that there are 
> updates available.

Got it. Release is deemed not important enough to warn about? no 
actually, it's different, I guess we never expect to bump only the 
release with a source level change - so in practice kernel could not 
warn that there is a newer release version since it would never know. In 
other words those ones would only be hitting linux-firmware, while minor 
changes would be kernel patches as well.

>> I also couldn't find guc_maj with grep so I guess it's some sort of a 
>> magic concatenation macro or what?
> 'guc_maj' is a macro parameter as per the definition of the macro three 
> lines above. According to where INTEL_GUC_FIRMWARE_DEFS is used, it 
> becomes either a mechanism for creating just a 'MODULE_FIRMWARE' 
> definition for the firmware file or a table entry giving all the version 
> information as well as the filename.

Doh thanks, macro magic was apparently impenetrable to me yesterday.

Regards,

Tvrtko