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

Lucas De Marchi
2021-07-06T21:09:30Z

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.

thanks
Lucas De Marchi