[PATCH AUTOSEL 4.20 50/81] drm/amdgpu: Implement doorbell self-ring for NBIO 7.4

[Sasha Levin]

From: Jay Cornwall <Jay.Cornwall at amd.com>

[ Upstream commit 12292519d919ecde92e7e7c8acbcdb9f0c7c6013 ]

Fixes doorbell reflection on Vega20.

Change-Id: I0495139d160a9032dff5977289b1eec11c16f781
Signed-off-by: Jay Cornwall <Jay.Cornwall at amd.com>
Reviewed-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/gpu/drm/amd/amdgpu/nbio_v7_4.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/nbio_v7_4.c b/drivers/gpu/drm/amd/amdgpu/nbio_v7_4.c
index f8cee95d61cc1..7d5cbadbe1cbc 100644
--- a/drivers/gpu/drm/amd/amdgpu/nbio_v7_4.c
+++ b/drivers/gpu/drm/amd/amdgpu/nbio_v7_4.c
@@ -92,7 +92,20 @@ static void nbio_v7_4_enable_doorbell_aperture(struct amdgpu_device *adev,
 static void nbio_v7_4_enable_doorbell_selfring_aperture(struct amdgpu_device *adev,
 							bool enable)
 {
+	u32 tmp = 0;
 
+	if (enable) {
+		tmp = REG_SET_FIELD(tmp, DOORBELL_SELFRING_GPA_APER_CNTL, DOORBELL_SELFRING_GPA_APER_EN, 1) |
+		      REG_SET_FIELD(tmp, DOORBELL_SELFRING_GPA_APER_CNTL, DOORBELL_SELFRING_GPA_APER_MODE, 1) |
+		      REG_SET_FIELD(tmp, DOORBELL_SELFRING_GPA_APER_CNTL, DOORBELL_SELFRING_GPA_APER_SIZE, 0);
+
+		WREG32_SOC15(NBIO, 0, mmDOORBELL_SELFRING_GPA_APER_BASE_LOW,
+			     lower_32_bits(adev->doorbell.base));
+		WREG32_SOC15(NBIO, 0, mmDOORBELL_SELFRING_GPA_APER_BASE_HIGH,
+			     upper_32_bits(adev->doorbell.base));
+	}
+
+	WREG32_SOC15(NBIO, 0, mmDOORBELL_SELFRING_GPA_APER_CNTL, tmp);
 }
 
 static void nbio_v7_4_ih_doorbell_range(struct amdgpu_device *adev,
-- 
2.19.1