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

Tvrtko Ursulin
2021-07-02T12:34:01Z

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.

Regards,

Tvrtko

> drm_printf(p, "media_ver: %u\n", info->media_ver);
> + drm_printf(p, "media_ver_release: %u\n", info->media_ver_release);
> drm_printf(p, "display_ver: %u\n", info->display.ver);
> drm_printf(p, "gt: %d\n", info->gt);
> drm_printf(p, "iommu: %s\n", iommu_name());
> diff --git a/drivers/gpu/drm/i915/intel_device_info.h b/drivers/gpu/drm/i915/intel_device_info.h
> index b326aff65cd6..944a5ff4df49 100644
> --- a/drivers/gpu/drm/i915/intel_device_info.h
> +++ b/drivers/gpu/drm/i915/intel_device_info.h
> @@ -162,7 +162,9 @@ enum intel_ppgtt_type {
>
> struct intel_device_info {
> u8 graphics_ver;
> + u8 graphics_ver_release;
> u8 media_ver;
> + u8 media_ver_release;
>
> u8 gt; /* GT number, 0 if undefined */
> intel_engine_mask_t platform_engine_mask; /* Engines supported by the HW */
>