SNB only - igt@i915_pm_rc6_residency@rc6-idle - fail - Failed assertion: idle < 1e-3

https://intel-gfx-ci.01.org/tree/drm-tip/IGT_5534/shard-iclb4/igt@i915_pm_rc6_residency@rc6-idle.html

Starting subtest: rc6-idle
(i915_pm_rc6_residency:1472) CRITICAL: Test assertion failure function rc6_idle, file ../tests/i915/i915_pm_rc6_residency.c:351:
(i915_pm_rc6_residency:1472) CRITICAL: Failed assertion: idle < 1e-3
Subtest rc6-idle failed.
**** DEBUG ****
(i915_pm_rc6_residency:1472) drmtest-DEBUG: Test requirement passed: is_i915_device(fd) && has_known_intel_chipset(fd)
(i915_pm_rc6_residency:1472) igt_debugfs-DEBUG: Opening debugfs directory '/sys/kernel/debug/dri/0'
(i915_pm_rc6_residency:1472) ioctl_wrappers-DEBUG: Test requirement passed: dir >= 0
(i915_pm_rc6_residency:1472) ioctl_wrappers-DEBUG: Test requirement passed: err == 0
(i915_pm_rc6_residency:1472) igt_debugfs-DEBUG: Opening debugfs directory '/sys/kernel/debug/dri/0'
(i915_pm_rc6_residency:1472) DEBUG: Test requirement passed: !(fd < 0 && errno == ENODEV)
(i915_pm_rc6_residency:1472) DEBUG: Test requirement passed: __pmu_wait_for_rc6(fd)
(i915_pm_rc6_residency:1472) DEBUG: slept=3000126466 perf=3000144165, rc6=3000144798
(i915_pm_rc6_residency:1472) INFO: Total energy used while idle: 696.6mJ
(i915_pm_rc6_residency:1472) CRITICAL: Test assertion failure function rc6_idle, file ../tests/i915/i915_pm_rc6_residency.c:351:
(i915_pm_rc6_residency:1472) CRITICAL: Failed assertion: idle < 1e-3
(i915_pm_rc6_residency:1472) igt_core-INFO: Stack trace:
(i915_pm_rc6_residency:1472) igt_core-INFO:   #0 ../lib/igt_core.c:1676 __igt_fail_assert()
(i915_pm_rc6_residency:1472) igt_core-INFO:   #1 ../lib/igt_rapl.h:84 __real_main402()
(i915_pm_rc6_residency:1472) igt_core-INFO:   #2 ../tests/i915/i915_pm_rc6_residency.c:402 main()
(i915_pm_rc6_residency:1472) igt_core-INFO:   #3 ../csu/libc-start.c:344 __libc_start_main()
(i915_pm_rc6_residency:1472) igt_core-INFO:   #4 [_start+0x2a]
****  END  ****