commit d967be9b80a5 ("drm/radeon/ci: disable needless sclk changes") introduces an unreachable if(C != C) conditional code section flagged by coccinelle script bad_conditional.cocci:
Add a comment to make it clear that this is intentional.
Fixes: d967be9b80a5 ("drm/radeon/ci: disable needless sclk changes")
Signed-off-by: Nicholas Mc Guire hofrat@osadl.org --- ./drivers/gpu/drm/radeon/ci_dpm.c:3847 bad/useless conditional <snip> 3845 } else { 3846 /* XXX check display min clock requirements */ 3847 if (CISLAND_MINIMUM_ENGINE_CLOCK != CISLAND_MINIMUM_ENGINE_CLOCK) 3848 pi->need_update_smu7_dpm_table |= DPMTABLE_UPDATE_SCLK; 3849 } <snip>
which is unreachable given the condition - as this seems to be an intentional disabling of that code section as stated in the commit message of d967be9b80a5 ("drm/radeon/ci: disable needless sclk changes") that introduced that change it should be at least commented
in drivers/gpu/drm/amd/amdgpu/ci_dpm.c at line 3988 3986 } else { 3987 /* XXX check display min clock requirements */ 3988 if (CISLAND_MINIMUM_ENGINE_CLOCK != CISLAND_MINIMUM_ENGINE_CLOCK) 3989 pi->need_update_smu7_dpm_table |= DPMTABLE_UPDATE_SCLK; 3990 }
The below patch adds a possibly suitable comment (taken directly from commit d967be9b80a5 ("drm/radeon/ci: disable needless sclk changes") But I�m not sure if such constructs really should be in the upstream kernel at all....
Patch was compile tested with x86_64_defconfig + CONFIG_DRM_RADEON=m
Patch is against 4.7.0-rc7 (localversion-next is -next-20160719)
drivers/gpu/drm/radeon/ci_dpm.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/radeon/ci_dpm.c b/drivers/gpu/drm/radeon/ci_dpm.c index 35e0fc3..7ba4508 100644 --- a/drivers/gpu/drm/radeon/ci_dpm.c +++ b/drivers/gpu/drm/radeon/ci_dpm.c @@ -3843,7 +3843,10 @@ static void ci_find_dpm_states_clocks_in_dpm_table(struct radeon_device *rdev, if (i >= sclk_table->count) { pi->need_update_smu7_dpm_table |= DPMTABLE_OD_UPDATE_SCLK; } else { - /* XXX check display min clock requirements */ + /* XXX The current code always reprogrammed the sclk levels, + * but we don't currently handle disp sclk requirements + * so just skip it. + */ if (CISLAND_MINIMUM_ENGINE_CLOCK != CISLAND_MINIMUM_ENGINE_CLOCK) pi->need_update_smu7_dpm_table |= DPMTABLE_UPDATE_SCLK; }