Re: [Intel-gfx] [PATCH 01/53] drm/i915: Add "release id" version

Jani Nikula
2021-07-07T08:35:06Z

On Tue, 06 Jul 2021, Lucas De Marchi <lucas.demarchi@intel.com> wrote:
> On Mon, Jul 05, 2021 at 02:52:31PM +0300, Jani Nikula wrote:
>>On Fri, 02 Jul 2021, Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> wrote:
>>> On 01/07/2021 21:23, Matt Roper wrote:
>>>> From: Lucas De Marchi <lucas.demarchi@intel.com>
>>>>
>>>> Besides the arch version returned by GRAPHICS_VER(), new platforms
>>>> contain a "release id" to make clear the difference from one platform to
>>>> another. Although for the first ones we may use them as if they were a
>>>
>>> What does "first ones" refer to here?
>>>
>>>> major/minor version, that is not true for all platforms: we may have a
>>>> `release_id == n` that is closer to `n - 2` than to `n - 1`.
>>>
>>> Hm this is a bit confusing. Is the sentence simply trying to say that,
>>> as the release id number is growing, hw capabilities are not simply
>>> accumulating but can be removed as well? Otherwise I am not sure how the
>>> user of these macros is supposed to act on this sentence.
>>>
>>>> However the release id number is not defined by hardware until we start
>>>> using the GMD_ID register. For the platforms before that register is
>>>> useful we will set the values in software and we can set them as we
>>>> please. So the plan is to set them so we can group different features
>>>> under a single GRAPHICS_VER_FULL() check.
>>>>
>>>> After GMD_ID is used, the usefulness of a "full version check" will be
>>>> greatly reduced and will be mostly used for deciding workarounds and a
>>>> few code paths. So it makes sense to keep it as a separate field from
>>>> graphics_ver.
>>>>
>>>> Also, currently there is not much use for the release id in media and
>>>> display, so keep them out.
>>>>
>>>> This is a mix of 2 independent changes: one by me and the other by Matt
>>>> Roper.
>>>>
>>>> Cc: Matt Roper <matthew.d.roper@intel.com>
>>>> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
>>>> Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
>>>> ---
>>>> drivers/gpu/drm/i915/i915_drv.h | 6 ++++++
>>>> drivers/gpu/drm/i915/intel_device_info.c | 2 ++
>>>> drivers/gpu/drm/i915/intel_device_info.h | 2 ++
>>>> 3 files changed, 10 insertions(+)
>>>>
>>>> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
>>>> index 6dff4ca01241..9639800485b9 100644
>>>> --- a/drivers/gpu/drm/i915/i915_drv.h
>>>> +++ b/drivers/gpu/drm/i915/i915_drv.h
>>>> @@ -1258,11 +1258,17 @@ static inline struct drm_i915_private *pdev_to_i915(struct pci_dev *pdev)
>>>> */
>>>> #define IS_GEN(dev_priv, n) (GRAPHICS_VER(dev_priv) == (n))
>>>>
>>>> +#define IP_VER(ver, release) ((ver) << 8 | (release))
>>>> +
>>>> #define GRAPHICS_VER(i915) (INTEL_INFO(i915)->graphics_ver)
>>>> +#define GRAPHICS_VER_FULL(i915) IP_VER(INTEL_INFO(i915)->graphics_ver, \
>>>> + INTEL_INFO(i915)->graphics_ver_release)
>>>> #define IS_GRAPHICS_VER(i915, from, until) \
>>>> (GRAPHICS_VER(i915) >= (from) && GRAPHICS_VER(i915) <= (until))
>>>>
>>>> #define MEDIA_VER(i915) (INTEL_INFO(i915)->media_ver)
>>>> +#define MEDIA_VER_FULL(i915) IP_VER(INTEL_INFO(i915)->media_ver, \
>>>> + INTEL_INFO(i915)->media_ver_release)
>>>> #define IS_MEDIA_VER(i915, from, until) \
>>>> (MEDIA_VER(i915) >= (from) && MEDIA_VER(i915) <= (until))
>>>>
>>>> diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
>>>> index 7eaa92fee421..e8ad14f002c1 100644
>>>> --- a/drivers/gpu/drm/i915/intel_device_info.c
>>>> +++ b/drivers/gpu/drm/i915/intel_device_info.c
>>>> @@ -97,7 +97,9 @@ void intel_device_info_print_static(const struct intel_device_info *info,
>>>> struct drm_printer *p)
>>>> {
>>>> drm_printf(p, "graphics_ver: %u\n", info->graphics_ver);
>>>> + drm_printf(p, "graphics_ver_release: %u\n", info->graphics_ver_release);
>>>
>>> I get the VER and VER_FULL in the macros but could 'ver' and
>>> 'ver_release' here and in the code simply be renamed to 'ver'/'version'
>>> and 'release'? Maybe it is just me but don't think I encountered the
>>> term "version release" before.
>>
>>Just bikeshedding here, but I thought of:
>>
>> if (info->grapics_ver_release)
>> drm_printf(p, "graphics_ver: %u.%u\n", info->graphics_ver, info->graphics_ver_release);
>> else
>> drm_printf(p, "graphics_ver: %u\n", info->graphics_ver);
>
> humn... a suggestion that I got internally a few week ago and I forgot
> to update this was that this doesn't need to be abbreviated in debugfs
> and could very well be:
>
> drm_printf(p, "graphics version: %u\n", info->graphics_ver);
> drm_printf(p, "graphics release: %u\n", info->graphics_ver_release);
>>
>>Also, I thought "x_ver" and "x_ver_release" sounds a bit odd, perhaps
>>having "x_ver" and "x_rel" is more natural?
>
> Not sure what direction to go now though. Maybe trying to put all
> suggestions together:
>
> if (info->graphics_rel)
> drm_printf(p, "graphics version: %u.%u\n", info->graphics_ver, info->graphics_rel);
> else
> drm_printf(p, "graphics version: %u\n", info->graphics_ver);
>
> One thing I like is that doing `| grep "graphics version"`
> gives all info you are searching for.

I'd like that, but this is all bikeshedding, really.

BR,
Jani.

>
>
> thanks
> Lucas De Marchi

--
Jani Nikula, Intel Open Source Graphics Center