From: Chris Wilson chris@chris-wilson.co.uk

commit e1eb075c5051987fbbadbc0fb8211679df657721 upstream.

If we use a non-forcewaked write to PMINTRMSK, it does not take effect until much later, if at all, causing a loss of RPS interrupts and no GPU reclocking, leaving the GPU running at the wrong frequency for long periods of time.

Reported-by: Francisco Jerez currojerez@riseup.net Suggested-by: Francisco Jerez currojerez@riseup.net Fixes: 35cc7f32c298 ("drm/i915/gt: Use non-forcewake writes for RPS") Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Francisco Jerez currojerez@riseup.net Cc: Mika Kuoppala mika.kuoppala@linux.intel.com Cc: Andi Shyti andi.shyti@intel.com Reviewed-by: Mika Kuoppala mika.kuoppala@linux.intel.com Reviewed-by: Andi Shyti andi.shyti@intel.com Reviewed-by: Francisco Jerez currojerez@riseup.net Cc: stable@vger.kernel.org # v5.6+ Link: https://patchwork.freedesktop.org/patch/msgid/20200415170318.16771-2-chris@c... (cherry picked from commit a080bd994c4023042a2b605c65fa10a25933f636) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/gt/intel_rps.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c index b2d2459..8accea0 100644 --- a/drivers/gpu/drm/i915/gt/intel_rps.c +++ b/drivers/gpu/drm/i915/gt/intel_rps.c @@ -83,7 +83,8 @@ static void rps_enable_interrupts(struct intel_rps *rps) gen6_gt_pm_enable_irq(gt, rps->pm_events); spin_unlock_irq(&gt->irq_lock);

- set(gt->uncore, GEN6_PMINTRMSK, rps_pm_mask(rps, rps->cur_freq)); + intel_uncore_write(gt->uncore, + GEN6_PMINTRMSK, rps_pm_mask(rps, rps->last_freq)); }

static void gen6_rps_reset_interrupts(struct intel_rps *rps) @@ -117,7 +118,8 @@ static void rps_disable_interrupts(struct intel_rps *rps)

rps->pm_events = 0;

- set(gt->uncore, GEN6_PMINTRMSK, rps_pm_sanitize_mask(rps, ~0u)); + intel_uncore_write(gt->uncore, + GEN6_PMINTRMSK, rps_pm_sanitize_mask(rps, ~0u));

spin_lock_irq(&gt->irq_lock); gen6_gt_pm_disable_irq(gt, GEN6_PM_RPS_EVENTS);