[PATCH 02/13] drm/amdgpu: doorbell registers need only be set once

[Andres Rodriguez]

The CP_MEC_DOORBELL_RANGE_* and CP_PQ_STATUS.DOORBELL_ENABLE registers
are not HQD specific.

They only need to be set once if at least 1 pipe requested doorbell
support.

Signed-off-by: Andres Rodriguez <andresx7 at gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h   | 1 +
 drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 147ce0e..9740800 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -1427,6 +1427,7 @@ struct amdgpu_device {
 	unsigned			num_rings;
 	struct amdgpu_ring		*rings[AMDGPU_MAX_RINGS];
 	bool				ib_pool_ready;
+	bool				doorbell_enabled;
 	struct amdgpu_sa_manager	ring_tmp_bo;
 
 	/* interrupts */
diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
index cf738e5..5d0e2c8 100644
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
@@ -4796,7 +4796,7 @@ static void gfx_v8_0_enable_doorbell(struct amdgpu_device *adev, bool enable)
 {
 	uint32_t tmp;
 
-	if (!enable)
+	if (!enable || adev->doorbell_enabled)
 		return;
 
 	if ((adev->asic_type == CHIP_CARRIZO) ||
@@ -4811,6 +4811,8 @@ static void gfx_v8_0_enable_doorbell(struct amdgpu_device *adev, bool enable)
 	tmp = RREG32(mmCP_PQ_STATUS);
 	tmp = REG_SET_FIELD(tmp, CP_PQ_STATUS, DOORBELL_ENABLE, 1);
 	WREG32(mmCP_PQ_STATUS, tmp);
+
+	adev->doorbell_enabled = true;
 }
 
 static int gfx_v8_0_mqd_commit(struct amdgpu_device *adev, struct vi_mqd *mqd)
@@ -5108,6 +5110,8 @@ static int gfx_v8_0_cp_resume(struct amdgpu_device *adev)
 {
 	int r;
 
+	adev->doorbell_enabled = false;
+
 	if (!(adev->flags & AMD_IS_APU))
 		gfx_v8_0_enable_gui_idle_interrupt(adev, false);
 
-- 
2.9.3