From 4c8c7743b53fb169ef2cb07a9eaa80c1b6c1d04e Mon Sep 17 00:00:00 2001 From: Akash Goel Date: Mon, 29 Jun 2015 14:50:20 +0530 Subject: [PATCH] drm/i915/skl: Ring frequency table programming changes Ring frequency table programming changes for SKL. No need for a floor on ring frequency, as the issue of performance impact with ring running below DDR frequency, is believed to be fixed on SKL v2: Removed the check for avoiding ring frequency programming for BXT (Rodrigo) Issue: VIZ-5144 Signed-off-by: Akash Goel Reviewed-by: Rodrigo Vivi Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_pm.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index ca82ad23e3f8..9d98f4074eae 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -5021,6 +5021,7 @@ static void __gen6_update_ring_freq(struct drm_device *dev) int min_freq = 15; unsigned int gpu_freq; unsigned int max_ia_freq, min_ring_freq; + unsigned int max_gpu_freq, min_gpu_freq; int scaling_factor = 180; struct cpufreq_policy *policy; @@ -5045,17 +5046,31 @@ static void __gen6_update_ring_freq(struct drm_device *dev) /* convert DDR frequency from units of 266.6MHz to bandwidth */ min_ring_freq = mult_frac(min_ring_freq, 8, 3); + if (IS_SKYLAKE(dev)) { + /* Convert GT frequency to 50 HZ units */ + min_gpu_freq = dev_priv->rps.min_freq / GEN9_FREQ_SCALER; + max_gpu_freq = dev_priv->rps.max_freq / GEN9_FREQ_SCALER; + } else { + min_gpu_freq = dev_priv->rps.min_freq; + max_gpu_freq = dev_priv->rps.max_freq; + } + /* * For each potential GPU frequency, load a ring frequency we'd like * to use for memory access. We do this by specifying the IA frequency * the PCU should use as a reference to determine the ring frequency. */ - for (gpu_freq = dev_priv->rps.max_freq; gpu_freq >= dev_priv->rps.min_freq; - gpu_freq--) { - int diff = dev_priv->rps.max_freq - gpu_freq; + for (gpu_freq = max_gpu_freq; gpu_freq >= min_gpu_freq; gpu_freq--) { + int diff = max_gpu_freq - gpu_freq; unsigned int ia_freq = 0, ring_freq = 0; - if (INTEL_INFO(dev)->gen >= 8) { + if (IS_SKYLAKE(dev)) { + /* + * ring_freq = 2 * GT. ring_freq is in 100MHz units + * No floor required for ring frequency on SKL. + */ + ring_freq = gpu_freq; + } else if (INTEL_INFO(dev)->gen >= 8) { /* max(2 * GT, DDR). NB: GT is 50MHz units */ ring_freq = max(min_ring_freq, gpu_freq); } else if (IS_HASWELL(dev)) { -- 2.20.1