Reviewed-by: Samuel Pitoiset samuel.pitoiset@gmail.com

On 03/14/2016 03:24 PM, Arnd Bergmann wrote:

gcc-6 warns about code in the nouveau driver that is obviously silly:

drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c: In function 'nv40_perfctr_next': drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c:62:19: warning: self-comparison always evaluats to false [-Wtautological-compare] if (pm->sequence != pm->sequence) {

The behavior was accidentally introduced in a patch described as "This is purely preparation for upcoming commits, there should be no code changes here.". As far as I can tell, that was true for the rest of that patch except for this one function, which has been changed to a NOP.

This patch restores the original behavior.

Signed-off-by: Arnd Bergmann arnd@arndb.de Fixes: 8c1aeaa13954 ("drm/nouveau/pm: cosmetic changes")

---

drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c b/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c index 4bef72a9d106..3fda594700e0 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c +++ b/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c @@ -59,9 +59,11 @@ static void nv40_perfctr_next(struct nvkm_pm *pm, struct nvkm_perfdom *dom) { struct nvkm_device *device = pm->engine.subdev.device;

• if (pm->sequence != pm->sequence) {

• struct nv40_pm *nv40pm = container_of(pm, struct nv40_pm, base);
• if (nv40pm->sequence != pm->sequence) { nvkm_wr32(device, 0x400084, 0x00000020);

• pm->sequence = pm->sequence;
  

• nv40pm->sequence = pm->sequence;
  

  } }