[PATCH 2/3] drm/amd/pm/si: Fix AC/DC switch notification

["Timur Kristóf" <timur.kristof@gmail.com>]

There were two mistakes in the previous implementation:

The check for ATOM_PP_PLATFORM_CAP_HARDWAREDC should be
inverted. We recently learned that the kernel should send
PPSMC_MSG_RunningOnAC when the flag is set, and not the
other way around.

The clocks also need to be recomputed, because the code in
the si_apply_state_adjust_rules() function selects different
limits on AC and DC.

Fixes: 2d071f6457af ("drm/amd/pm/si: Notify the SMC when switching to AC")
Tested-by: Jeremy Klarenbeek <jeremy.klarenbeek99@gmail.com>
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
---
 drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c b/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c
index 6a54566d1a68..a0c28de691f8 100644
--- a/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c
+++ b/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c
@@ -3892,13 +3892,16 @@ static void si_notify_hw_of_powersource(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 
-	/* Check if the platform already manages the AC/DC switch via dedicated GPIO. */
-	if (adev->pm.dpm.platform_caps & ATOM_PP_PLATFORM_CAP_HARDWAREDC)
-		return;
-
-	/* The SMU automatically notices DC, but needs to be notified when switching to AC. */
-	if (adev->pm.ac_power)
+	/*
+	 * Check if the platform already manages the AC/DC switch via dedicated GPIO.
+	 * Otherwise SMU automatically notices DC, but needs to be notified of AC.
+	 */
+	if (adev->pm.ac_power &&
+	    (adev->pm.dpm.platform_caps & ATOM_PP_PLATFORM_CAP_HARDWAREDC))
 		amdgpu_si_send_msg_to_smc(adev, PPSMC_MSG_RunningOnAC);
+
+	/* Recompute clocks with updated max_limits. */
+	amdgpu_legacy_dpm_compute_clocks(adev);
 }
 
 static PPSMC_Result si_send_msg_to_smc_with_parameter(struct amdgpu_device *adev,
-- 
2.54.0