drm/amd/display: Check if clock source in use before disabling

[why]
We are disabling clock source while other pipes are still using
it, because we don't verify the number of pipes that share it.

[how]
- Adding a function in resources to return the number of pipes
sharing the clock source.
- Checking that no one is sharing the clock source before disabling

Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
index 964ba1a..1644f2a 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -268,24 +268,30 @@ bool resource_construct(
 
        return true;
 }
+static int find_matching_clock_source(
+               const struct resource_pool *pool,
+               struct clock_source *clock_source)
+{
+
+       int i;
 
+       for (i = 0; i < pool->clk_src_count; i++) {
+               if (pool->clock_sources[i] == clock_source)
+                       return i;
+       }
+       return -1;
+}
 
 void resource_unreference_clock_source(
                struct resource_context *res_ctx,
                const struct resource_pool *pool,
                struct clock_source *clock_source)
 {
-       int i;
-
-       for (i = 0; i < pool->clk_src_count; i++) {
-               if (pool->clock_sources[i] != clock_source)
-                       continue;
+       int i = find_matching_clock_source(pool, clock_source);
 
+       if (i > -1)
                res_ctx->clock_source_ref_count[i]--;
 
-               break;
-       }
-
        if (pool->dp_clock_source == clock_source)
                res_ctx->dp_clock_source_ref_count--;
 }
@@ -295,19 +301,31 @@ void resource_reference_clock_source(
                const struct resource_pool *pool,
                struct clock_source *clock_source)
 {
-       int i;
-       for (i = 0; i < pool->clk_src_count; i++) {
-               if (pool->clock_sources[i] != clock_source)
-                       continue;
+       int i = find_matching_clock_source(pool, clock_source);
 
+       if (i > -1)
                res_ctx->clock_source_ref_count[i]++;
-               break;
-       }
 
        if (pool->dp_clock_source == clock_source)
                res_ctx->dp_clock_source_ref_count++;
 }
 
+int resource_get_clock_source_reference(
+               struct resource_context *res_ctx,
+               const struct resource_pool *pool,
+               struct clock_source *clock_source)
+{
+       int i = find_matching_clock_source(pool, clock_source);
+
+       if (i > -1)
+               return res_ctx->clock_source_ref_count[i];
+
+       if (pool->dp_clock_source == clock_source)
+               return res_ctx->dp_clock_source_ref_count;
+
+       return -1;
+}
+
 bool resource_are_streams_timing_synchronizable(
        struct dc_stream_state *stream1,
        struct dc_stream_state *stream2)

diff --git a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
index 1d98e36..5450d4d 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
@@ -1908,7 +1908,9 @@ static void dce110_reset_hw_ctx_wrap(
                        pipe_ctx_old->plane_res.mi->funcs->free_mem_input(
                                        pipe_ctx_old->plane_res.mi, dc->current_state->stream_count);
 
-                       if (old_clk)
+                       if (old_clk && 0 == resource_get_clock_source_reference(&context->res_ctx,
+                                                                               dc->res_pool,
+                                                                               old_clk))
                                old_clk->funcs->cs_power_down(old_clk);
 
                        dc->hwss.disable_plane(dc, pipe_ctx_old);

diff --git a/drivers/gpu/drm/amd/display/dc/inc/resource.h b/drivers/gpu/drm/amd/display/dc/inc/resource.h
index e92facb..5b32100 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/inc/resource.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/resource.h
@@ -103,6 +103,11 @@ void resource_reference_clock_source(
                const struct resource_pool *pool,
                struct clock_source *clock_source);
 
+int resource_get_clock_source_reference(
+               struct resource_context *res_ctx,
+               const struct resource_pool *pool,
+               struct clock_source *clock_source);
+
 bool resource_are_streams_timing_synchronizable(
                struct dc_stream_state *stream1,
                struct dc_stream_state *stream2);