On Thu, 2018-02-01 at 12:34 +0100, Hans de Goede wrote:
Hi All,
For the "Improved Laptop Battery Life" feature:
https://fedoraproject.org/wiki/Changes/ImprovedLaptopBatteryLife
I'm working on for Fedora 28 I would like to also try and enable
Panel Self Refresh on laptops with Intel graphics, some quick tests
have shown this to save another 0.5W (when idle / nothing on the
screen changes). This is currently off be default because it is
known to cause issues on some devices. So I think we will probably
need a white- or black-list. But first we need more data on this.
If you can spare 10 minutes, please see my blogpost for how to test
this and send me a mail with the info request in the blogpost:
https://hansdegoede.livejournal.com/18653.html
ThinkPad X1 Carbon 3rd gen (i7-5600U) kernel 4.14.14-300.fc27.x86_64.
I added i915.enable_psr=1 but it doesn't seem to have enabled PSR on
the panel:
Sink_Support: no
Source_OK: no
Enabled: no
Active: no
Busy frontbuffer bits: 0x000
Re-enable work scheduled: no
Main link in standby mode: no
HW Enabled & Active bit: no
Performance_Counter: 0
Shouldn't Sink_Support:no mean that the panel doesn't support PSR? At
least that's what would be implied by intel_dp.c:
/* Check if the panel supports PSR */
drm_dp_dpcd_read(&intel_dp->aux, DP_PSR_SUPPORT,
intel_dp->psr_dpcd,
sizeof(intel_dp->psr_dpcd));
if (intel_dp->psr_dpcd[0] & DP_PSR_IS_SUPPORTED) {
dev_priv->psr.sink_support = true;
DRM_DEBUG_KMS("Detected EDP PSR Panel.\n");
}
if (INTEL_GEN(dev_priv) >= 9 &&
(intel_dp->psr_dpcd[0] & DP_PSR2_IS_SUPPORTED)) {
uint8_t frame_sync_cap;
dev_priv->psr.sink_support = true;
Dan