drm/i915: expose command stream timestamp frequency to userspace

We use to have this fixed per generation, but starting with CNL userspace
cannot tell just off the PCI ID. Let's make this information available. This
is particularly useful for performance monitoring where much of the
normalization work is done using those timestamps (this include pipeline
statistics in both GL & Vulkan as well as OA reports).

v2: Use variables for 24MHz/19.2MHz values (Ewelina)
    Renamed function & coding style (Sagar)

v3: Fix frequency read on Broadwell (Sagar)
    Fix missing divide by 4 on <= gen4 (Sagar)

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Tested-by: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171110190845.32574-7-lionel.g.landwerlin@intel.com
This commit is contained in:
Lionel Landwerlin
2017-11-10 19:08:44 +00:00
parent 95690a02fb
commit dab9178333
6 changed files with 141 additions and 0 deletions

View File

@@ -481,6 +481,12 @@ typedef struct drm_i915_irq_wait {
*/
#define I915_PARAM_HAS_CONTEXT_ISOLATION 50
/* Frequency of the command streamer timestamps given by the *_TIMESTAMP
* registers. This used to be fixed per platform but from CNL onwards, this
* might vary depending on the parts.
*/
#define I915_PARAM_CS_TIMESTAMP_FREQUENCY 51
typedef struct drm_i915_getparam {
__s32 param;
/*