[Intel-gfx] [PATCH 2/2] drm/i915/guc: Turn on GuC/HuC auto mode

[Srivatsa, Anusha]

>-----Original Message-----
>From: Wajdeczko, Michal
>Sent: Wednesday, July 10, 2019 7:27 AM
>To: intel-gfx at lists.freedesktop.org; Joonas Lahtinen
><joonas.lahtinen at linux.intel.com>; Srivatsa, Anusha
><anusha.srivatsa at intel.com>; Ye, Tony <tony.ye at intel.com>
>Cc: Ceraolo Spurio, Daniele <daniele.ceraolospurio at intel.com>; Chris Wilson
><chris at chris-wilson.co.uk>
>Subject: Re: [PATCH 2/2] drm/i915/guc: Turn on GuC/HuC auto mode
>
>On Tue, 09 Jul 2019 16:17:02 +0200, Joonas Lahtinen
><joonas.lahtinen at linux.intel.com> wrote:
>
>> Better subject would be: "Enable HuC (through GuC) on supported
>> platforms"
>
>Such subject sounds better, but on one hand it does not reflect real code change
>(since we are not explicitly enabling HuC, but instead we are just letting the driver
>enable GuC/HuC to whatever mode it decides), but on other hand this is what
>actual outcome of the change is (as i915 currently enables GuC loading with HuC
>authentication on every platform where corresponding firmwares are
>defined/available, and nothing more).
>
>Please confirm if you still opt-in to use your subject.
>
>>
>> Quoting Michal Wajdeczko (2019-07-03 14:36:40)
>>> GuC firmware is now mature, so let it run by default.
>>
>> That's bit of a misleading statement (in more than one way).
>
>It's mature enough to perform HuC authentication, and we don't expect more
>from it ;)
>
>>
>> "Enable loading HuC firmware (through GuC) to unlock advanced video
>> codecs on supported platforms.
>>
>> GuC firmware is required to authenticate the HuC firmware, which is a
>> requirement for it to operate."
>
>To some extend this duplicates existing "DOC: HuC Firmware"
>Do we need to repeat that again here?
>
>>
>> Has the most recent firmware been merged to linux-firmware and is it
>> present in our CI systems?
>
>My understanding is: No and Yes.
>Maybe Anusha can provide more details here.

Waiting on the firmware to get merged to linux-firmware. Sent the PR.
The latest firmware is however available on our CI.

Anusha 
>>
>> It would also be good to list what kind of tests have been run to
>> ensure that there are no regressions,
>
>I'm afraid on IGT level we don't have HuC tests.
>But media team was using modparam override to force GuC/HuC for a while,
>Tony do you have such test list/results handy?
>
>> and which platforms
>> this change affects.
>
>This change affects all platforms where we have GuC/HuC firmwares defined, so:
>SKL, BXT, KBL, CFL, ICL.
>
>Note that we'll still have possibility to tweak that inside driver, as auto mode is
>just moving responsibility what can be enabled from the user to the i915.
>
>>
>> Regards, Joonas
>>
>>> Note that today GuC is only used for HuC authentication.
>>>
>>> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
>>> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
>>> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
>>> Cc: Chris Wilson <chris at chris-wilson.co.uk>
>>> ---
>>>  drivers/gpu/drm/i915/i915_params.h | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/i915_params.h
>>> b/drivers/gpu/drm/i915/i915_params.h
>>> index d29ade3b7de6..5736c55694fe 100644
>>> --- a/drivers/gpu/drm/i915/i915_params.h
>>> +++ b/drivers/gpu/drm/i915/i915_params.h
>>> @@ -54,7 +54,7 @@ struct drm_printer;
>>>         param(int, disable_power_well, -1) \
>>>         param(int, enable_ips, 1) \
>>>         param(int, invert_brightness, 0) \
>>> -       param(int, enable_guc, 0) \
>>> +       param(int, enable_guc, -1) \
>>>         param(int, guc_log_level, -1) \
>>>         param(char *, guc_firmware_path, NULL) \
>>>         param(char *, huc_firmware_path, NULL) \
>>> --
>>> 2.19.2