drm/i915: Extract GT ring management
authorAndi Shyti <andi.shyti@intel.com>
Sun, 20 Oct 2019 18:41:39 +0000 (19:41 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Sun, 20 Oct 2019 19:45:18 +0000 (20:45 +0100)
Although the ring management is much smaller compared to the other GT
power management functions, continue the theme of extracting it out of
the huge intel_pm.c for maintenance.

Based on a patch by Chris Wilson.

Signed-off-by: Andi Shyti <andi.shyti@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191020184139.9145-1-chris@chris-wilson.co.uk
drivers/gpu/drm/i915/Makefile
drivers/gpu/drm/i915/gt/intel_gt_types.h
drivers/gpu/drm/i915/gt/intel_llc.c [new file with mode: 0644]
drivers/gpu/drm/i915/gt/intel_llc.h [new file with mode: 0644]
drivers/gpu/drm/i915/gt/intel_llc_types.h [new file with mode: 0644]
drivers/gpu/drm/i915/gt/selftest_gt_pm.c
drivers/gpu/drm/i915/gt/selftest_llc.c [new file with mode: 0644]
drivers/gpu/drm/i915/gt/selftest_llc.h [new file with mode: 0644]
drivers/gpu/drm/i915/i915_drv.h
drivers/gpu/drm/i915/intel_pm.c

index e791d93..a16a2da 100644 (file)
@@ -87,6 +87,7 @@ gt-y += \
        gt/intel_gt_pm_irq.o \
        gt/intel_gt_requests.o \
        gt/intel_hangcheck.o \
+       gt/intel_llc.o \
        gt/intel_lrc.o \
        gt/intel_rc6.o \
        gt/intel_renderstate.o \
index be4b263..ae4aaf7 100644 (file)
@@ -17,6 +17,7 @@
 
 #include "i915_vma.h"
 #include "intel_engine_types.h"
+#include "intel_llc_types.h"
 #include "intel_reset_types.h"
 #include "intel_rc6_types.h"
 #include "intel_wakeref.h"
@@ -79,6 +80,7 @@ struct intel_gt {
         */
        intel_wakeref_t awake;
 
+       struct intel_llc llc;
        struct intel_rc6 rc6;
 
        struct blocking_notifier_head pm_notifications;
diff --git a/drivers/gpu/drm/i915/gt/intel_llc.c b/drivers/gpu/drm/i915/gt/intel_llc.c
new file mode 100644 (file)
index 0000000..35093eb
--- /dev/null
@@ -0,0 +1,161 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#include <linux/cpufreq.h>
+
+#include "i915_drv.h"
+#include "intel_gt.h"
+#include "intel_llc.h"
+#include "intel_sideband.h"
+
+struct ia_constants {
+       unsigned int min_gpu_freq;
+       unsigned int max_gpu_freq;
+
+       unsigned int min_ring_freq;
+       unsigned int max_ia_freq;
+};
+
+static struct intel_gt *llc_to_gt(struct intel_llc *llc)
+{
+       return container_of(llc, struct intel_gt, llc);
+}
+
+static unsigned int cpu_max_MHz(void)
+{
+       struct cpufreq_policy *policy;
+       unsigned int max_khz;
+
+       policy = cpufreq_cpu_get(0);
+       if (policy) {
+               max_khz = policy->cpuinfo.max_freq;
+               cpufreq_cpu_put(policy);
+       } else {
+               /*
+                * Default to measured freq if none found, PCU will ensure we
+                * don't go over
+                */
+               max_khz = tsc_khz;
+       }
+
+       return max_khz / 1000;
+}
+
+static bool get_ia_constants(struct intel_llc *llc,
+                            struct ia_constants *consts)
+{
+       struct drm_i915_private *i915 = llc_to_gt(llc)->i915;
+       struct intel_rps *rps = &i915->gt_pm.rps;
+
+       if (rps->max_freq <= rps->min_freq)
+               return false;
+
+       consts->max_ia_freq = cpu_max_MHz();
+
+       consts->min_ring_freq =
+               intel_uncore_read(llc_to_gt(llc)->uncore, DCLK) & 0xf;
+       /* convert DDR frequency from units of 266.6MHz to bandwidth */
+       consts->min_ring_freq = mult_frac(consts->min_ring_freq, 8, 3);
+
+       consts->min_gpu_freq = rps->min_freq;
+       consts->max_gpu_freq = rps->max_freq;
+       if (INTEL_GEN(i915) >= 9) {
+               /* Convert GT frequency to 50 HZ units */
+               consts->min_gpu_freq /= GEN9_FREQ_SCALER;
+               consts->max_gpu_freq /= GEN9_FREQ_SCALER;
+       }
+
+       return true;
+}
+
+static void calc_ia_freq(struct intel_llc *llc,
+                        unsigned int gpu_freq,
+                        const struct ia_constants *consts,
+                        unsigned int *out_ia_freq,
+                        unsigned int *out_ring_freq)
+{
+       struct drm_i915_private *i915 = llc_to_gt(llc)->i915;
+       const int diff = consts->max_gpu_freq - gpu_freq;
+       unsigned int ia_freq = 0, ring_freq = 0;
+
+       if (INTEL_GEN(i915) >= 9) {
+               /*
+                * 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_GEN(i915) >= 8) {
+               /* max(2 * GT, DDR). NB: GT is 50MHz units */
+               ring_freq = max(consts->min_ring_freq, gpu_freq);
+       } else if (IS_HASWELL(i915)) {
+               ring_freq = mult_frac(gpu_freq, 5, 4);
+               ring_freq = max(consts->min_ring_freq, ring_freq);
+               /* leave ia_freq as the default, chosen by cpufreq */
+       } else {
+               const int min_freq = 15;
+               const int scale = 180;
+
+               /*
+                * On older processors, there is no separate ring
+                * clock domain, so in order to boost the bandwidth
+                * of the ring, we need to upclock the CPU (ia_freq).
+                *
+                * For GPU frequencies less than 750MHz,
+                * just use the lowest ring freq.
+                */
+               if (gpu_freq < min_freq)
+                       ia_freq = 800;
+               else
+                       ia_freq = consts->max_ia_freq - diff * scale / 2;
+               ia_freq = DIV_ROUND_CLOSEST(ia_freq, 100);
+       }
+
+       *out_ia_freq = ia_freq;
+       *out_ring_freq = ring_freq;
+}
+
+static void gen6_update_ring_freq(struct intel_llc *llc)
+{
+       struct drm_i915_private *i915 = llc_to_gt(llc)->i915;
+       struct ia_constants consts;
+       unsigned int gpu_freq;
+
+       if (!get_ia_constants(llc, &consts))
+               return;
+
+       /*
+        * 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 = consts.max_gpu_freq;
+            gpu_freq >= consts.min_gpu_freq;
+            gpu_freq--) {
+               unsigned int ia_freq, ring_freq;
+
+               calc_ia_freq(llc, gpu_freq, &consts, &ia_freq, &ring_freq);
+               sandybridge_pcode_write(i915,
+                                       GEN6_PCODE_WRITE_MIN_FREQ_TABLE,
+                                       ia_freq << GEN6_PCODE_FREQ_IA_RATIO_SHIFT |
+                                       ring_freq << GEN6_PCODE_FREQ_RING_RATIO_SHIFT |
+                                       gpu_freq);
+       }
+}
+
+void intel_llc_enable(struct intel_llc *llc)
+{
+       if (HAS_LLC(llc_to_gt(llc)->i915))
+               gen6_update_ring_freq(llc);
+}
+
+void intel_llc_disable(struct intel_llc *llc)
+{
+       /* Currently there is no HW configuration to be done to disable. */
+}
+
+#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
+#include "selftest_llc.c"
+#endif
diff --git a/drivers/gpu/drm/i915/gt/intel_llc.h b/drivers/gpu/drm/i915/gt/intel_llc.h
new file mode 100644 (file)
index 0000000..ef09a89
--- /dev/null
@@ -0,0 +1,15 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#ifndef INTEL_LLC_H
+#define INTEL_LLC_H
+
+struct intel_llc;
+
+void intel_llc_enable(struct intel_llc *llc);
+void intel_llc_disable(struct intel_llc *llc);
+
+#endif /* INTEL_LLC_H */
diff --git a/drivers/gpu/drm/i915/gt/intel_llc_types.h b/drivers/gpu/drm/i915/gt/intel_llc_types.h
new file mode 100644 (file)
index 0000000..ecad468
--- /dev/null
@@ -0,0 +1,13 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#ifndef INTEL_LLC_TYPES_H
+#define INTEL_LLC_TYPES_H
+
+struct intel_llc {
+};
+
+#endif /* INTEL_LLC_TYPES_H */
index 87985bd..5d42903 100644 (file)
@@ -5,6 +5,8 @@
  * Copyright © 2019 Intel Corporation
  */
 
+#include "selftest_llc.h"
+
 static int live_gt_resume(void *arg)
 {
        struct intel_gt *gt = arg;
@@ -32,6 +34,13 @@ static int live_gt_resume(void *arg)
                        err = -EINVAL;
                        break;
                }
+
+               err = st_llc_verify(&gt->llc);
+               if (err) {
+                       pr_err("llc state not restored upon resume!\n");
+                       intel_gt_set_wedged_on_init(gt);
+                       break;
+               }
        } while (!__igt_timeout(end_time, NULL));
 
        return err;
diff --git a/drivers/gpu/drm/i915/gt/selftest_llc.c b/drivers/gpu/drm/i915/gt/selftest_llc.c
new file mode 100644 (file)
index 0000000..a705778
--- /dev/null
@@ -0,0 +1,77 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#include "intel_pm.h" /* intel_gpu_freq() */
+#include "selftest_llc.h"
+
+static int gen6_verify_ring_freq(struct intel_llc *llc)
+{
+       struct drm_i915_private *i915 = llc_to_gt(llc)->i915;
+       struct ia_constants consts;
+       intel_wakeref_t wakeref;
+       unsigned int gpu_freq;
+       int err = 0;
+
+       wakeref = intel_runtime_pm_get(llc_to_gt(llc)->uncore->rpm);
+
+       if (!get_ia_constants(llc, &consts)) {
+               err = -ENODEV;
+               goto out_rpm;
+       }
+
+       for (gpu_freq = consts.min_gpu_freq;
+            gpu_freq <= consts.max_gpu_freq;
+            gpu_freq++) {
+               unsigned int ia_freq, ring_freq, found;
+               u32 val;
+
+               calc_ia_freq(llc, gpu_freq, &consts, &ia_freq, &ring_freq);
+
+               val = gpu_freq;
+               if (sandybridge_pcode_read(i915,
+                                          GEN6_PCODE_READ_MIN_FREQ_TABLE,
+                                          &val, NULL)) {
+                       pr_err("Failed to read freq table[%d], range [%d, %d]\n",
+                              gpu_freq, consts.min_gpu_freq, consts.max_gpu_freq);
+                       err = -ENXIO;
+                       break;
+               }
+
+               found = (val >> 0) & 0xff;
+               if (found != ia_freq) {
+                       pr_err("Min freq table(%d/[%d, %d]):%dMHz did not match expected CPU freq, found %d, expected %d\n",
+                              gpu_freq, consts.min_gpu_freq, consts.max_gpu_freq,
+                              intel_gpu_freq(i915, gpu_freq * (INTEL_GEN(i915) >= 9 ? GEN9_FREQ_SCALER : 1)),
+                              found, ia_freq);
+                       err = -EINVAL;
+                       break;
+               }
+
+               found = (val >> 8) & 0xff;
+               if (found != ring_freq) {
+                       pr_err("Min freq table(%d/[%d, %d]):%dMHz did not match expected ring freq, found %d, expected %d\n",
+                              gpu_freq, consts.min_gpu_freq, consts.max_gpu_freq,
+                              intel_gpu_freq(i915, gpu_freq * (INTEL_GEN(i915) >= 9 ? GEN9_FREQ_SCALER : 1)),
+                              found, ring_freq);
+                       err = -EINVAL;
+                       break;
+               }
+       }
+
+out_rpm:
+       intel_runtime_pm_put(llc_to_gt(llc)->uncore->rpm, wakeref);
+       return err;
+}
+
+int st_llc_verify(struct intel_llc *llc)
+{
+       int err = 0;
+
+       if (HAS_LLC(llc_to_gt(llc)->i915))
+               err = gen6_verify_ring_freq(llc);
+
+       return err;
+}
diff --git a/drivers/gpu/drm/i915/gt/selftest_llc.h b/drivers/gpu/drm/i915/gt/selftest_llc.h
new file mode 100644 (file)
index 0000000..873f896
--- /dev/null
@@ -0,0 +1,14 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#ifndef SELFTEST_LLC_H
+#define SELFTEST_LLC_H
+
+struct intel_llc;
+
+int st_llc_verify(struct intel_llc *llc);
+
+#endif /* SELFTEST_LLC_H */
index db3c3a0..16b85c7 100644 (file)
@@ -605,13 +605,8 @@ struct intel_rps {
        struct intel_rps_ei ei;
 };
 
-struct intel_llc_pstate {
-       bool enabled;
-};
-
 struct intel_gen6_power_mgmt {
        struct intel_rps rps;
-       struct intel_llc_pstate llc_pstate;
 };
 
 /* defined intel_pm.c */
index 2b71d52..3622344 100644 (file)
@@ -25,7 +25,6 @@
  *
  */
 
-#include <linux/cpufreq.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
 
@@ -38,6 +37,8 @@
 #include "display/intel_fbc.h"
 #include "display/intel_sprite.h"
 
+#include "gt/intel_llc.h"
+
 #include "i915_drv.h"
 #include "i915_irq.h"
 #include "i915_trace.h"
@@ -7030,93 +7031,6 @@ static void gen6_enable_rps(struct drm_i915_private *dev_priv)
        intel_uncore_forcewake_put(&dev_priv->uncore, FORCEWAKE_ALL);
 }
 
-static void gen6_update_ring_freq(struct drm_i915_private *dev_priv)
-{
-       struct intel_rps *rps = &dev_priv->gt_pm.rps;
-       const int min_freq = 15;
-       const int scaling_factor = 180;
-       unsigned int gpu_freq;
-       unsigned int max_ia_freq, min_ring_freq;
-       unsigned int max_gpu_freq, min_gpu_freq;
-       struct cpufreq_policy *policy;
-
-       lockdep_assert_held(&rps->lock);
-
-       if (rps->max_freq <= rps->min_freq)
-               return;
-
-       policy = cpufreq_cpu_get(0);
-       if (policy) {
-               max_ia_freq = policy->cpuinfo.max_freq;
-               cpufreq_cpu_put(policy);
-       } else {
-               /*
-                * Default to measured freq if none found, PCU will ensure we
-                * don't go over
-                */
-               max_ia_freq = tsc_khz;
-       }
-
-       /* Convert from kHz to MHz */
-       max_ia_freq /= 1000;
-
-       min_ring_freq = I915_READ(DCLK) & 0xf;
-       /* convert DDR frequency from units of 266.6MHz to bandwidth */
-       min_ring_freq = mult_frac(min_ring_freq, 8, 3);
-
-       min_gpu_freq = rps->min_freq;
-       max_gpu_freq = rps->max_freq;
-       if (IS_GEN9_BC(dev_priv) || INTEL_GEN(dev_priv) >= 10) {
-               /* Convert GT frequency to 50 HZ units */
-               min_gpu_freq /= GEN9_FREQ_SCALER;
-               max_gpu_freq /= GEN9_FREQ_SCALER;
-       }
-
-       /*
-        * 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 = max_gpu_freq; gpu_freq >= min_gpu_freq; gpu_freq--) {
-               const int diff = max_gpu_freq - gpu_freq;
-               unsigned int ia_freq = 0, ring_freq = 0;
-
-               if (IS_GEN9_BC(dev_priv) || INTEL_GEN(dev_priv) >= 10) {
-                       /*
-                        * 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_GEN(dev_priv) >= 8) {
-                       /* max(2 * GT, DDR). NB: GT is 50MHz units */
-                       ring_freq = max(min_ring_freq, gpu_freq);
-               } else if (IS_HASWELL(dev_priv)) {
-                       ring_freq = mult_frac(gpu_freq, 5, 4);
-                       ring_freq = max(min_ring_freq, ring_freq);
-                       /* leave ia_freq as the default, chosen by cpufreq */
-               } else {
-                       /* On older processors, there is no separate ring
-                        * clock domain, so in order to boost the bandwidth
-                        * of the ring, we need to upclock the CPU (ia_freq).
-                        *
-                        * For GPU frequencies less than 750MHz,
-                        * just use the lowest ring freq.
-                        */
-                       if (gpu_freq < min_freq)
-                               ia_freq = 800;
-                       else
-                               ia_freq = max_ia_freq - ((diff * scaling_factor) / 2);
-                       ia_freq = DIV_ROUND_CLOSEST(ia_freq, 100);
-               }
-
-               sandybridge_pcode_write(dev_priv,
-                                       GEN6_PCODE_WRITE_MIN_FREQ_TABLE,
-                                       ia_freq << GEN6_PCODE_FREQ_IA_RATIO_SHIFT |
-                                       ring_freq << GEN6_PCODE_FREQ_RING_RATIO_SHIFT |
-                                       gpu_freq);
-       }
-}
-
 static int cherryview_rps_max_freq(struct drm_i915_private *dev_priv)
 {
        u32 val, rp0;
@@ -7965,18 +7879,6 @@ void intel_sanitize_gt_powersave(struct drm_i915_private *dev_priv)
                gen6_reset_rps_interrupts(dev_priv);
 }
 
-static inline void intel_disable_llc_pstate(struct drm_i915_private *i915)
-{
-       lockdep_assert_held(&i915->gt_pm.rps.lock);
-
-       if (!i915->gt_pm.llc_pstate.enabled)
-               return;
-
-       /* Currently there is no HW configuration to be done to disable. */
-
-       i915->gt_pm.llc_pstate.enabled = false;
-}
-
 static void intel_disable_rps(struct drm_i915_private *dev_priv)
 {
        lockdep_assert_held(&dev_priv->gt_pm.rps.lock);
@@ -8004,23 +7906,11 @@ void intel_disable_gt_powersave(struct drm_i915_private *dev_priv)
 
        intel_disable_rps(dev_priv);
        if (HAS_LLC(dev_priv))
-               intel_disable_llc_pstate(dev_priv);
+               intel_llc_disable(&dev_priv->gt.llc);
 
        mutex_unlock(&dev_priv->gt_pm.rps.lock);
 }
 
-static inline void intel_enable_llc_pstate(struct drm_i915_private *i915)
-{
-       lockdep_assert_held(&i915->gt_pm.rps.lock);
-
-       if (i915->gt_pm.llc_pstate.enabled)
-               return;
-
-       gen6_update_ring_freq(i915);
-
-       i915->gt_pm.llc_pstate.enabled = true;
-}
-
 static void intel_enable_rps(struct drm_i915_private *dev_priv)
 {
        struct intel_rps *rps = &dev_priv->gt_pm.rps;
@@ -8064,8 +7954,8 @@ void intel_enable_gt_powersave(struct drm_i915_private *dev_priv)
 
        if (HAS_RPS(dev_priv))
                intel_enable_rps(dev_priv);
-       if (HAS_LLC(dev_priv))
-               intel_enable_llc_pstate(dev_priv);
+
+       intel_llc_enable(&dev_priv->gt.llc);
 
        mutex_unlock(&dev_priv->gt_pm.rps.lock);
 }