disable Panel Self Refresh (PSR) by default in inteldrm

After i915_drv.c 1.144 PSR changed to being on by default.
On a TUXEDO InfinityBook Pro 14 Gen6 (Tiger Lake) this introduced screen
flicker.  Reported and tested by Matthias Schmidt.

Should also avoid flicker problem on Dell XPS 13 7390 (Comet Lake)
reported by James Cook.

diff --git a/sys/dev/pci/drm/i915/i915_drv.c b/sys/dev/pci/drm/i915/i915_drv.c
index 6d4bb89..ad36e5a 100644 (file)
--- a/sys/dev/pci/drm/i915/i915_drv.c
+++ b/sys/dev/pci/drm/i915/i915_drv.c
@@ -2414,6 +2414,7 @@ inteldrm_attach(struct device *parent, struct device *self, void *aux)
        i915_params_copy(&dev_priv->params, &i915_modparams);
        dev_priv->params.enable_guc = 0;
        dev_priv->params.request_timeout_ms = 0;
+       dev_priv->params.enable_psr = 0;
 
        /* Setup the write-once "constant" device info */
        device_info = mkwrite_device_info(dev_priv);