[PATCH AUTOSEL 6.2 06/37] drm/amd/display: Enable HostVM based on rIOMMU active

[Sasha Levin]

From: Gabe Teeger <gabe.teeger at amd.com>

[ Upstream commit 97fa4dfa66fdd52ad3d0c9fadeaaa1e87605bac7 ]

[Why]
There is underflow and flickering occuring. The
underflow stops when hostvm is forced to active.
According to policy, hostvm should be enabled if riommu
is active, but this is not taken into account when
deciding whether to enable hostvm.

[What]
For DCN314, set hostvm to true if riommu is active.

Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas at amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo at amd.com>
Signed-off-by: Gabe Teeger <gabe.teeger at amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler 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/display/dc/dml/dcn314/dcn314_fpu.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn314/dcn314_fpu.c b/drivers/gpu/drm/amd/display/dc/dml/dcn314/dcn314_fpu.c
index 6a1cf6adea77d..8fa47233bc0a5 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn314/dcn314_fpu.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn314/dcn314_fpu.c
@@ -308,6 +308,10 @@ int dcn314_populate_dml_pipes_from_context_fpu(struct dc *dc, struct dc_state *c
 				pipe->plane_state->src_rect.width < pipe->plane_state->dst_rect.width))
 			upscaled = true;
 
+		/* Apply HostVM policy - either based on hypervisor globally enabled, or rIOMMU active */
+		if (dc->debug.dml_hostvm_override == DML_HOSTVM_NO_OVERRIDE)
+			pipes[i].pipe.src.hostvm = dc->vm_pa_config.is_hvm_enabled || dc->res_pool->hubbub->riommu_active;
+
 		/*
 		 * Immediate flip can be set dynamically after enabling the plane.
 		 * We need to require support for immediate flip or underflow can be
-- 
2.39.2