drm/radeon/dpm: resume fixes for some systems

Setting the power state prior to restoring the display
hardware leads to blank screens on some systems.  Drop
the power state set from dpm resume.  The power state
will get set as part of the mode set sequence.  Also
add an explicit power state set after mode set resume
to cover PX and headless systems.

bug:
https://bugzilla.kernel.org/show_bug.cgi?id=76761

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/atombios_crtc.c

@@ -270,8 +270,6 @@ void atombios_crtc_dpms(struct drm_crtc *crtc, int mode)
 	switch (mode) {
 	case DRM_MODE_DPMS_ON:
 		radeon_crtc->enabled = true;
-		/* adjust pm to dpms changes BEFORE enabling crtcs */
-		radeon_pm_compute_clocks(rdev);
 		atombios_enable_crtc(crtc, ATOM_ENABLE);
 		if (ASIC_IS_DCE3(rdev) && !ASIC_IS_DCE6(rdev))
 			atombios_enable_crtc_memreq(crtc, ATOM_ENABLE);
@@ -289,10 +287,10 @@ void atombios_crtc_dpms(struct drm_crtc *crtc, int mode)
 			atombios_enable_crtc_memreq(crtc, ATOM_DISABLE);
 		atombios_enable_crtc(crtc, ATOM_DISABLE);
 		radeon_crtc->enabled = false;
-		/* adjust pm to dpms changes AFTER disabling crtcs */
-		radeon_pm_compute_clocks(rdev);
 		break;
 	}
+	/* adjust pm to dpms */
+	radeon_pm_compute_clocks(rdev);
 }
 
 static void

drivers/gpu/drm/radeon/radeon_device.c

@@ -1558,6 +1558,10 @@ int radeon_resume_kms(struct drm_device *dev, bool resume, bool fbcon)
 
 	drm_kms_helper_poll_enable(dev);
 
+	/* set the power state here in case we are a PX system or headless */
+	if ((rdev->pm.pm_method == PM_METHOD_DPM) && rdev->pm.dpm_enabled)
+		radeon_pm_compute_clocks(rdev);
+
 	if (fbcon) {
 		radeon_fbdev_set_suspend(rdev, 0);
 		console_unlock();

drivers/gpu/drm/radeon/radeon_pm.c

@@ -1104,7 +1104,6 @@ static void radeon_pm_resume_dpm(struct radeon_device *rdev)
 	if (ret)
 		goto dpm_resume_fail;
 	rdev->pm.dpm_enabled = true;
-	radeon_pm_compute_clocks(rdev);
 	return;
 
 dpm_resume_fail: