drm/panfrost: Add SYSTEM_TIMESTAMP and SYSTEM_TIMESTAMP_FREQUENCY parameters

Expose system timestamp and frequency supported by the GPU.

Mali uses an external timer as GPU system time. On ARM, this is wired to
the generic arch timer so we wire cntfrq_el0 as device frequency.

This new uAPI will be used in Mesa to implement timestamp queries and
VK_KHR_calibrated_timestamps.

v2:
- Rewrote to use GPU timestamp register
- Add missing include for arch_timer_get_cntfrq
- Rework commit message

v3:
- Move panfrost_cycle_counter_get and panfrost_cycle_counter_put to
  panfrost_ioctl_query_timestamp
- Handle possible overflow in panfrost_timestamp_read

Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240819080224.24914-2-mary.guillemard@collabora.com

include/uapi/drm/panfrost_drm.h

@@ -172,6 +172,8 @@ enum drm_panfrost_param {
 	DRM_PANFROST_PARAM_NR_CORE_GROUPS,
 	DRM_PANFROST_PARAM_THREAD_TLS_ALLOC,
 	DRM_PANFROST_PARAM_AFBC_FEATURES,
+	DRM_PANFROST_PARAM_SYSTEM_TIMESTAMP,
+	DRM_PANFROST_PARAM_SYSTEM_TIMESTAMP_FREQUENCY,
 };
 
 struct drm_panfrost_get_param {