| Message ID | 20180320135842.11752-1-mika.kuoppala@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Quoting Mika Kuoppala (2018-03-20 13:58:42) > We do end up setting ring frequencies on a hardware > which is not yet there wrt runtime pm enablement. > > Instead of ending up in an endless loop iterating through > frequencies if min and max frequencies are still set to zero, > warn and bail out early. Hmm, if you are hitting this in practice, I would just go with if (rps->max_freq <= rps->min_freq) return; I'm sure we have warnings else where for invalid min/max freq. Don't worry about min_ring_freq unless you have a document that says otherwise. -Chris
Chris Wilson <chris@chris-wilson.co.uk> writes: > Quoting Mika Kuoppala (2018-03-20 13:58:42) >> We do end up setting ring frequencies on a hardware >> which is not yet there wrt runtime pm enablement. >> >> Instead of ending up in an endless loop iterating through >> frequencies if min and max frequencies are still set to zero, >> warn and bail out early. > > Hmm, if you are hitting this in practice, I > would just go with I did. > > if (rps->max_freq <= rps->min_freq) > return; Ok, this is enough to fix the loop.. > > I'm sure we have warnings else where for invalid min/max freq. but I didn't bump into any of these. > > Don't worry about min_ring_freq unless you have a document that says > otherwise. Yeah, different story for that one. -Mika
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index dd5ddb77b306..61378222f4dd 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -6918,6 +6918,11 @@ static void gen6_update_ring_freq(struct drm_i915_private *dev_priv) /* convert DDR frequency from units of 266.6MHz to bandwidth */ min_ring_freq = mult_frac(min_ring_freq, 8, 3); + if (WARN_ON(rps->min_freq == 0 || + rps->max_freq == 0 || + min_ring_freq == 0)) + return; + min_gpu_freq = rps->min_freq; max_gpu_freq = rps->max_freq; if (IS_GEN9_BC(dev_priv) || IS_CANNONLAKE(dev_priv)) {
We do end up setting ring frequencies on a hardware which is not yet there wrt runtime pm enablement. Instead of ending up in an endless loop iterating through frequencies if min and max frequencies are still set to zero, warn and bail out early. Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> --- drivers/gpu/drm/i915/intel_pm.c | 5 +++++ 1 file changed, 5 insertions(+)