From: Damien Lespiau Date: Fri, 26 Jun 2015 17:34:29 +0000 (+0100) Subject: drm/i915/skl: Skip remaining dividers when deviation is 0 X-Git-Tag: v4.3-rc1~75^2~36^2~140 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e7ad987832637701fc723ac2c1580c30c191bca6;p=karo-tx-linux.git drm/i915/skl: Skip remaining dividers when deviation is 0 We can't improve a 0 deviation, so when we find such a divider, skip the remaining ones they won't be better. This short-circuit the search for 34 of the 373 test frequencies in the corresponding i-g-t test (tools/skl_compute_wrpll) v2: Place the short-circuiting code in skl_compute_wrpll() (Paulo) (I'm sure nobody will notice the spurious removal of a blank line) Reviewed-by: Paulo Zanoni Suggested-by: Paulo Zanoni Signed-off-by: Damien Lespiau Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index f6b3ccc4ab66..42c14870ef43 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -1149,7 +1149,6 @@ static void skl_wrpll_try_divider(struct skl_wrpll_context *ctx, ctx->dco_freq = dco_freq; ctx->p = divider; } - } static void skl_wrpll_get_multipliers(unsigned int p, @@ -1315,9 +1314,17 @@ skl_ddi_calculate_wrpll(int clock /* in Hz */, dco_central_freq[dco], dco_freq, p); + /* + * Skip the remaining dividers if we're sure to + * have found the definitive divider, we can't + * improve a 0 deviation. + */ + if (ctx.min_deviation == 0) + goto skip_remaining_dividers; } } +skip_remaining_dividers: /* * If a solution is found with an even divider, prefer * this one.