drm/amd/display: Populate hostvm parameter before DML calculation

[Why]
If the system does not have hostvm enabled, disabling it for
DML validation will allow more modes to pass at lower voltage
levels.

[How]
When initializing HostVM save state to hubbub and read back
when populating DML pipes from context.
Signed-off-by: NSung Lee <sung.lee@amd.com>
Acked-by: NBindu Ramamurthy <bindu.r@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hubbub.c

@@ -99,6 +99,8 @@ void dcn21_dchvm_init(struct hubbub *hubbub)
 
 		//Poll until HOSTVM_PREFETCH_DONE = 1
 		REG_WAIT(DCHVM_RIOMMU_STAT0, HOSTVM_PREFETCH_DONE, 1, 5, 100);
+
+		hubbub->riommu_active = true;
 	}
 }
 

drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c

@@ -1886,7 +1886,7 @@ static int dcn21_populate_dml_pipes_from_context(
 
 	for (i = 0; i < pipe_cnt; i++) {
 
-		pipes[i].pipe.src.hostvm = 1;
+		pipes[i].pipe.src.hostvm = dc->res_pool->hubbub->riommu_active;
 		pipes[i].pipe.src.gpuvm = 1;
 	}
 

drivers/gpu/drm/amd/display/dc/inc/hw/dchubbub.h

@@ -157,6 +157,7 @@ struct hubbub_funcs {
 struct hubbub {
 	const struct hubbub_funcs *funcs;
 	struct dc_context *ctx;
+	bool riommu_active;
 };
 
 #endif