drm/amd: Fix initialization mistake for NBIO 7.7.0

There is a strapping issue on NBIO 7.7.0 that can lead to spurious PME
events while in the D0 state.

Co-developed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://lore.kernel.org/r/20241112161142.28974-1-mario.limonciello@amd.com
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 447a54a0f79c9a409ceaa17804bdd2e0206397b9)
Cc: stable@vger.kernel.org
diff --git a/drivers/gpu/drm/amd/amdgpu/nbio_v7_7.c b/drivers/gpu/drm/amd/amdgpu/nbio_v7_7.c
index fb37e35..1ac7303 100644
--- a/drivers/gpu/drm/amd/amdgpu/nbio_v7_7.c
+++ b/drivers/gpu/drm/amd/amdgpu/nbio_v7_7.c
@@ -247,6 +247,12 @@ static void nbio_v7_7_init_registers(struct amdgpu_device *adev)
 	if (def != data)
 		WREG32_SOC15(NBIO, 0, regBIF0_PCIE_MST_CTRL_3, data);
 
+	switch (adev->ip_versions[NBIO_HWIP][0]) {
+	case IP_VERSION(7, 7, 0):
+		data = RREG32_SOC15(NBIO, 0, regRCC_DEV0_EPF5_STRAP4) & ~BIT(23);
+		WREG32_SOC15(NBIO, 0, regRCC_DEV0_EPF5_STRAP4, data);
+		break;
+	}
 }
 
 static void nbio_v7_7_update_medium_grain_clock_gating(struct amdgpu_device *adev,