drm/i915: Split out runtime configuration of device info to its own file
authorChris Wilson <chris@chris-wilson.co.uk>
Tue, 5 Jul 2016 09:40:20 +0000 (10:40 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Tue, 5 Jul 2016 10:53:27 +0000 (11:53 +0100)
Let's reclaim a few hundred lines from i915_drv.c by splitting out the
runtime configuration of the "constant" dev_priv->info.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1467711623-2905-1-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
drivers/gpu/drm/i915/Makefile
drivers/gpu/drm/i915/i915_drv.c
drivers/gpu/drm/i915/i915_drv.h
drivers/gpu/drm/i915/intel_device_info.c [new file with mode: 0644]

index 618293c..684fc1c 100644 (file)
@@ -14,6 +14,7 @@ i915-y := i915_drv.o \
           i915_suspend.o \
          i915_sysfs.o \
          intel_csr.o \
+         intel_device_info.o \
          intel_pm.o \
          intel_runtime_pm.o
 
index 695001f..87295f6 100644 (file)
@@ -748,394 +748,6 @@ static int i915_kick_out_vgacon(struct drm_i915_private *dev_priv)
 }
 #endif
 
-static void i915_dump_device_info(struct drm_i915_private *dev_priv)
-{
-       const struct intel_device_info *info = &dev_priv->info;
-
-#define PRINT_S(name) "%s"
-#define SEP_EMPTY
-#define PRINT_FLAG(name) info->name ? #name "," : ""
-#define SEP_COMMA ,
-       DRM_DEBUG_DRIVER("i915 device info: gen=%i, pciid=0x%04x rev=0x%02x flags="
-                        DEV_INFO_FOR_EACH_FLAG(PRINT_S, SEP_EMPTY),
-                        info->gen,
-                        dev_priv->dev->pdev->device,
-                        dev_priv->dev->pdev->revision,
-                        DEV_INFO_FOR_EACH_FLAG(PRINT_FLAG, SEP_COMMA));
-#undef PRINT_S
-#undef SEP_EMPTY
-#undef PRINT_FLAG
-#undef SEP_COMMA
-}
-
-static void cherryview_sseu_info_init(struct drm_device *dev)
-{
-       struct drm_i915_private *dev_priv = dev->dev_private;
-       struct intel_device_info *info;
-       u32 fuse, eu_dis;
-
-       info = (struct intel_device_info *)&dev_priv->info;
-       fuse = I915_READ(CHV_FUSE_GT);
-
-       info->slice_total = 1;
-
-       if (!(fuse & CHV_FGT_DISABLE_SS0)) {
-               info->subslice_per_slice++;
-               eu_dis = fuse & (CHV_FGT_EU_DIS_SS0_R0_MASK |
-                                CHV_FGT_EU_DIS_SS0_R1_MASK);
-               info->eu_total += 8 - hweight32(eu_dis);
-       }
-
-       if (!(fuse & CHV_FGT_DISABLE_SS1)) {
-               info->subslice_per_slice++;
-               eu_dis = fuse & (CHV_FGT_EU_DIS_SS1_R0_MASK |
-                                CHV_FGT_EU_DIS_SS1_R1_MASK);
-               info->eu_total += 8 - hweight32(eu_dis);
-       }
-
-       info->subslice_total = info->subslice_per_slice;
-       /*
-        * CHV expected to always have a uniform distribution of EU
-        * across subslices.
-       */
-       info->eu_per_subslice = info->subslice_total ?
-                               info->eu_total / info->subslice_total :
-                               0;
-       /*
-        * CHV supports subslice power gating on devices with more than
-        * one subslice, and supports EU power gating on devices with
-        * more than one EU pair per subslice.
-       */
-       info->has_slice_pg = 0;
-       info->has_subslice_pg = (info->subslice_total > 1);
-       info->has_eu_pg = (info->eu_per_subslice > 2);
-}
-
-static void gen9_sseu_info_init(struct drm_device *dev)
-{
-       struct drm_i915_private *dev_priv = dev->dev_private;
-       struct intel_device_info *info;
-       int s_max = 3, ss_max = 4, eu_max = 8;
-       int s, ss;
-       u32 fuse2, s_enable, ss_disable, eu_disable;
-       u8 eu_mask = 0xff;
-
-       info = (struct intel_device_info *)&dev_priv->info;
-       fuse2 = I915_READ(GEN8_FUSE2);
-       s_enable = (fuse2 & GEN8_F2_S_ENA_MASK) >>
-                  GEN8_F2_S_ENA_SHIFT;
-       ss_disable = (fuse2 & GEN9_F2_SS_DIS_MASK) >>
-                    GEN9_F2_SS_DIS_SHIFT;
-
-       info->slice_total = hweight32(s_enable);
-       /*
-        * The subslice disable field is global, i.e. it applies
-        * to each of the enabled slices.
-       */
-       info->subslice_per_slice = ss_max - hweight32(ss_disable);
-       info->subslice_total = info->slice_total *
-                              info->subslice_per_slice;
-
-       /*
-        * Iterate through enabled slices and subslices to
-        * count the total enabled EU.
-       */
-       for (s = 0; s < s_max; s++) {
-               if (!(s_enable & (0x1 << s)))
-                       /* skip disabled slice */
-                       continue;
-
-               eu_disable = I915_READ(GEN9_EU_DISABLE(s));
-               for (ss = 0; ss < ss_max; ss++) {
-                       int eu_per_ss;
-
-                       if (ss_disable & (0x1 << ss))
-                               /* skip disabled subslice */
-                               continue;
-
-                       eu_per_ss = eu_max - hweight8((eu_disable >> (ss*8)) &
-                                                     eu_mask);
-
-                       /*
-                        * Record which subslice(s) has(have) 7 EUs. we
-                        * can tune the hash used to spread work among
-                        * subslices if they are unbalanced.
-                        */
-                       if (eu_per_ss == 7)
-                               info->subslice_7eu[s] |= 1 << ss;
-
-                       info->eu_total += eu_per_ss;
-               }
-       }
-
-       /*
-        * SKL is expected to always have a uniform distribution
-        * of EU across subslices with the exception that any one
-        * EU in any one subslice may be fused off for die
-        * recovery. BXT is expected to be perfectly uniform in EU
-        * distribution.
-       */
-       info->eu_per_subslice = info->subslice_total ?
-                               DIV_ROUND_UP(info->eu_total,
-                                            info->subslice_total) : 0;
-       /*
-        * SKL supports slice power gating on devices with more than
-        * one slice, and supports EU power gating on devices with
-        * more than one EU pair per subslice. BXT supports subslice
-        * power gating on devices with more than one subslice, and
-        * supports EU power gating on devices with more than one EU
-        * pair per subslice.
-       */
-       info->has_slice_pg = ((IS_SKYLAKE(dev) || IS_KABYLAKE(dev)) &&
-                              (info->slice_total > 1));
-       info->has_subslice_pg = (IS_BROXTON(dev) && (info->subslice_total > 1));
-       info->has_eu_pg = (info->eu_per_subslice > 2);
-
-       if (IS_BROXTON(dev)) {
-#define IS_SS_DISABLED(_ss_disable, ss)    (_ss_disable & (0x1 << ss))
-               /*
-                * There is a HW issue in 2x6 fused down parts that requires
-                * Pooled EU to be enabled as a WA. The pool configuration
-                * changes depending upon which subslice is fused down. This
-                * doesn't affect if the device has all 3 subslices enabled.
-                */
-               /* WaEnablePooledEuFor2x6:bxt */
-               info->has_pooled_eu = ((info->subslice_per_slice == 3) ||
-                                      (info->subslice_per_slice == 2 &&
-                                       INTEL_REVID(dev) < BXT_REVID_C0));
-
-               info->min_eu_in_pool = 0;
-               if (info->has_pooled_eu) {
-                       if (IS_SS_DISABLED(ss_disable, 0) ||
-                           IS_SS_DISABLED(ss_disable, 2))
-                               info->min_eu_in_pool = 3;
-                       else if (IS_SS_DISABLED(ss_disable, 1))
-                               info->min_eu_in_pool = 6;
-                       else
-                               info->min_eu_in_pool = 9;
-               }
-#undef IS_SS_DISABLED
-       }
-}
-
-static void broadwell_sseu_info_init(struct drm_device *dev)
-{
-       struct drm_i915_private *dev_priv = dev->dev_private;
-       struct intel_device_info *info;
-       const int s_max = 3, ss_max = 3, eu_max = 8;
-       int s, ss;
-       u32 fuse2, eu_disable[s_max], s_enable, ss_disable;
-
-       fuse2 = I915_READ(GEN8_FUSE2);
-       s_enable = (fuse2 & GEN8_F2_S_ENA_MASK) >> GEN8_F2_S_ENA_SHIFT;
-       ss_disable = (fuse2 & GEN8_F2_SS_DIS_MASK) >> GEN8_F2_SS_DIS_SHIFT;
-
-       eu_disable[0] = I915_READ(GEN8_EU_DISABLE0) & GEN8_EU_DIS0_S0_MASK;
-       eu_disable[1] = (I915_READ(GEN8_EU_DISABLE0) >> GEN8_EU_DIS0_S1_SHIFT) |
-                       ((I915_READ(GEN8_EU_DISABLE1) & GEN8_EU_DIS1_S1_MASK) <<
-                        (32 - GEN8_EU_DIS0_S1_SHIFT));
-       eu_disable[2] = (I915_READ(GEN8_EU_DISABLE1) >> GEN8_EU_DIS1_S2_SHIFT) |
-                       ((I915_READ(GEN8_EU_DISABLE2) & GEN8_EU_DIS2_S2_MASK) <<
-                        (32 - GEN8_EU_DIS1_S2_SHIFT));
-
-
-       info = (struct intel_device_info *)&dev_priv->info;
-       info->slice_total = hweight32(s_enable);
-
-       /*
-        * The subslice disable field is global, i.e. it applies
-        * to each of the enabled slices.
-        */
-       info->subslice_per_slice = ss_max - hweight32(ss_disable);
-       info->subslice_total = info->slice_total * info->subslice_per_slice;
-
-       /*
-        * Iterate through enabled slices and subslices to
-        * count the total enabled EU.
-        */
-       for (s = 0; s < s_max; s++) {
-               if (!(s_enable & (0x1 << s)))
-                       /* skip disabled slice */
-                       continue;
-
-               for (ss = 0; ss < ss_max; ss++) {
-                       u32 n_disabled;
-
-                       if (ss_disable & (0x1 << ss))
-                               /* skip disabled subslice */
-                               continue;
-
-                       n_disabled = hweight8(eu_disable[s] >> (ss * eu_max));
-
-                       /*
-                        * Record which subslices have 7 EUs.
-                        */
-                       if (eu_max - n_disabled == 7)
-                               info->subslice_7eu[s] |= 1 << ss;
-
-                       info->eu_total += eu_max - n_disabled;
-               }
-       }
-
-       /*
-        * BDW is expected to always have a uniform distribution of EU across
-        * subslices with the exception that any one EU in any one subslice may
-        * be fused off for die recovery.
-        */
-       info->eu_per_subslice = info->subslice_total ?
-               DIV_ROUND_UP(info->eu_total, info->subslice_total) : 0;
-
-       /*
-        * BDW supports slice power gating on devices with more than
-        * one slice.
-        */
-       info->has_slice_pg = (info->slice_total > 1);
-       info->has_subslice_pg = 0;
-       info->has_eu_pg = 0;
-}
-
-/*
- * Determine various intel_device_info fields at runtime.
- *
- * Use it when either:
- *   - it's judged too laborious to fill n static structures with the limit
- *     when a simple if statement does the job,
- *   - run-time checks (eg read fuse/strap registers) are needed.
- *
- * This function needs to be called:
- *   - after the MMIO has been setup as we are reading registers,
- *   - after the PCH has been detected,
- *   - before the first usage of the fields it can tweak.
- */
-static void intel_device_info_runtime_init(struct drm_device *dev)
-{
-       struct drm_i915_private *dev_priv = dev->dev_private;
-       struct intel_device_info *info;
-       enum pipe pipe;
-
-       info = (struct intel_device_info *)&dev_priv->info;
-
-       /*
-        * Skylake and Broxton currently don't expose the topmost plane as its
-        * use is exclusive with the legacy cursor and we only want to expose
-        * one of those, not both. Until we can safely expose the topmost plane
-        * as a DRM_PLANE_TYPE_CURSOR with all the features exposed/supported,
-        * we don't expose the topmost plane at all to prevent ABI breakage
-        * down the line.
-        */
-       if (IS_BROXTON(dev)) {
-               info->num_sprites[PIPE_A] = 2;
-               info->num_sprites[PIPE_B] = 2;
-               info->num_sprites[PIPE_C] = 1;
-       } else if (IS_VALLEYVIEW(dev) || IS_CHERRYVIEW(dev))
-               for_each_pipe(dev_priv, pipe)
-                       info->num_sprites[pipe] = 2;
-       else
-               for_each_pipe(dev_priv, pipe)
-                       info->num_sprites[pipe] = 1;
-
-       if (i915.disable_display) {
-               DRM_INFO("Display disabled (module parameter)\n");
-               info->num_pipes = 0;
-       } else if (info->num_pipes > 0 &&
-                  (IS_GEN7(dev_priv) || IS_GEN8(dev_priv)) &&
-                  HAS_PCH_SPLIT(dev)) {
-               u32 fuse_strap = I915_READ(FUSE_STRAP);
-               u32 sfuse_strap = I915_READ(SFUSE_STRAP);
-
-               /*
-                * SFUSE_STRAP is supposed to have a bit signalling the display
-                * is fused off. Unfortunately it seems that, at least in
-                * certain cases, fused off display means that PCH display
-                * reads don't land anywhere. In that case, we read 0s.
-                *
-                * On CPT/PPT, we can detect this case as SFUSE_STRAP_FUSE_LOCK
-                * should be set when taking over after the firmware.
-                */
-               if (fuse_strap & ILK_INTERNAL_DISPLAY_DISABLE ||
-                   sfuse_strap & SFUSE_STRAP_DISPLAY_DISABLED ||
-                   (dev_priv->pch_type == PCH_CPT &&
-                    !(sfuse_strap & SFUSE_STRAP_FUSE_LOCK))) {
-                       DRM_INFO("Display fused off, disabling\n");
-                       info->num_pipes = 0;
-               } else if (fuse_strap & IVB_PIPE_C_DISABLE) {
-                       DRM_INFO("PipeC fused off\n");
-                       info->num_pipes -= 1;
-               }
-       } else if (info->num_pipes > 0 && IS_GEN9(dev_priv)) {
-               u32 dfsm = I915_READ(SKL_DFSM);
-               u8 disabled_mask = 0;
-               bool invalid;
-               int num_bits;
-
-               if (dfsm & SKL_DFSM_PIPE_A_DISABLE)
-                       disabled_mask |= BIT(PIPE_A);
-               if (dfsm & SKL_DFSM_PIPE_B_DISABLE)
-                       disabled_mask |= BIT(PIPE_B);
-               if (dfsm & SKL_DFSM_PIPE_C_DISABLE)
-                       disabled_mask |= BIT(PIPE_C);
-
-               num_bits = hweight8(disabled_mask);
-
-               switch (disabled_mask) {
-               case BIT(PIPE_A):
-               case BIT(PIPE_B):
-               case BIT(PIPE_A) | BIT(PIPE_B):
-               case BIT(PIPE_A) | BIT(PIPE_C):
-                       invalid = true;
-                       break;
-               default:
-                       invalid = false;
-               }
-
-               if (num_bits > info->num_pipes || invalid)
-                       DRM_ERROR("invalid pipe fuse configuration: 0x%x\n",
-                                 disabled_mask);
-               else
-                       info->num_pipes -= num_bits;
-       }
-
-       /* Initialize slice/subslice/EU info */
-       if (IS_CHERRYVIEW(dev))
-               cherryview_sseu_info_init(dev);
-       else if (IS_BROADWELL(dev))
-               broadwell_sseu_info_init(dev);
-       else if (INTEL_INFO(dev)->gen >= 9)
-               gen9_sseu_info_init(dev);
-
-       info->has_snoop = !info->has_llc;
-
-       /* Snooping is broken on BXT A stepping. */
-       if (IS_BXT_REVID(dev, 0, BXT_REVID_A1))
-               info->has_snoop = false;
-
-       DRM_DEBUG_DRIVER("slice total: %u\n", info->slice_total);
-       DRM_DEBUG_DRIVER("subslice total: %u\n", info->subslice_total);
-       DRM_DEBUG_DRIVER("subslice per slice: %u\n", info->subslice_per_slice);
-       DRM_DEBUG_DRIVER("EU total: %u\n", info->eu_total);
-       DRM_DEBUG_DRIVER("EU per subslice: %u\n", info->eu_per_subslice);
-       DRM_DEBUG_DRIVER("has slice power gating: %s\n",
-                        info->has_slice_pg ? "y" : "n");
-       DRM_DEBUG_DRIVER("has subslice power gating: %s\n",
-                        info->has_subslice_pg ? "y" : "n");
-       DRM_DEBUG_DRIVER("has EU power gating: %s\n",
-                        info->has_eu_pg ? "y" : "n");
-
-       i915.enable_execlists =
-               intel_sanitize_enable_execlists(dev_priv,
-                                               i915.enable_execlists);
-
-       /*
-        * i915.enable_ppgtt is read-only, so do an early pass to validate the
-        * user's requested state against the hardware/driver capabilities.  We
-        * do this now so that we can print out any log messages once rather
-        * than every time we check intel_enable_ppgtt().
-        */
-       i915.enable_ppgtt =
-               intel_sanitize_enable_ppgtt(dev_priv, i915.enable_ppgtt);
-       DRM_DEBUG_DRIVER("ppgtt mode: %i\n", i915.enable_ppgtt);
-}
-
 static void intel_init_dpio(struct drm_i915_private *dev_priv)
 {
        /*
@@ -1213,7 +825,7 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv,
                return -ENODEV;
 
        /* Setup the write-once "constant" device info */
-       device_info = (struct intel_device_info *)&dev_priv->info;
+       device_info = mkwrite_device_info(dev_priv);
        memcpy(device_info, match_info, sizeof(*device_info));
        device_info->device_id = dev_priv->drm.pdev->device;
 
@@ -1254,7 +866,7 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv,
 
        intel_display_crc_init(&dev_priv->drm);
 
-       i915_dump_device_info(dev_priv);
+       intel_device_info_dump(dev_priv);
 
        /* Not all pre-production machines fall into this category, only the
         * very first ones. Almost everything should work, except for maybe
@@ -1368,6 +980,23 @@ static void i915_driver_cleanup_mmio(struct drm_i915_private *dev_priv)
        pci_dev_put(dev_priv->bridge_dev);
 }
 
+static void intel_sanitize_options(struct drm_i915_private *dev_priv)
+{
+       i915.enable_execlists =
+               intel_sanitize_enable_execlists(dev_priv,
+                                               i915.enable_execlists);
+
+       /*
+        * i915.enable_ppgtt is read-only, so do an early pass to validate the
+        * user's requested state against the hardware/driver capabilities.  We
+        * do this now so that we can print out any log messages once rather
+        * than every time we check intel_enable_ppgtt().
+        */
+       i915.enable_ppgtt =
+               intel_sanitize_enable_ppgtt(dev_priv, i915.enable_ppgtt);
+       DRM_DEBUG_DRIVER("ppgtt mode: %i\n", i915.enable_ppgtt);
+}
+
 /**
  * i915_driver_init_hw - setup state requiring device access
  * @dev_priv: device private
@@ -1385,7 +1014,9 @@ static int i915_driver_init_hw(struct drm_i915_private *dev_priv)
        if (i915_inject_load_failure())
                return -ENODEV;
 
-       intel_device_info_runtime_init(dev);
+       intel_device_info_runtime_init(dev_priv);
+
+       intel_sanitize_options(dev_priv);
 
        ret = i915_ggtt_init_hw(dev);
        if (ret)
index 594ddbb..d33b370 100644 (file)
@@ -3750,6 +3750,16 @@ static inline void intel_register_dsm_handler(void) { return; }
 static inline void intel_unregister_dsm_handler(void) { return; }
 #endif /* CONFIG_ACPI */
 
+/* intel_device_info.c */
+static inline struct intel_device_info *
+mkwrite_device_info(struct drm_i915_private *dev_priv)
+{
+       return (struct intel_device_info *)&dev_priv->info;
+}
+
+void intel_device_info_runtime_init(struct drm_i915_private *dev_priv);
+void intel_device_info_dump(struct drm_i915_private *dev_priv);
+
 /* modesetting */
 extern void intel_modeset_init_hw(struct drm_device *dev);
 extern void intel_modeset_init(struct drm_device *dev);
diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
new file mode 100644 (file)
index 0000000..cba137f
--- /dev/null
@@ -0,0 +1,388 @@
+/*
+ * Copyright © 2016 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ */
+
+#include "i915_drv.h"
+
+void intel_device_info_dump(struct drm_i915_private *dev_priv)
+{
+       const struct intel_device_info *info = &dev_priv->info;
+
+#define PRINT_S(name) "%s"
+#define SEP_EMPTY
+#define PRINT_FLAG(name) info->name ? #name "," : ""
+#define SEP_COMMA ,
+       DRM_DEBUG_DRIVER("i915 device info: gen=%i, pciid=0x%04x rev=0x%02x flags="
+                        DEV_INFO_FOR_EACH_FLAG(PRINT_S, SEP_EMPTY),
+                        info->gen,
+                        dev_priv->drm.pdev->device,
+                        dev_priv->drm.pdev->revision,
+                        DEV_INFO_FOR_EACH_FLAG(PRINT_FLAG, SEP_COMMA));
+#undef PRINT_S
+#undef SEP_EMPTY
+#undef PRINT_FLAG
+#undef SEP_COMMA
+}
+
+static void cherryview_sseu_info_init(struct drm_i915_private *dev_priv)
+{
+       struct intel_device_info *info = mkwrite_device_info(dev_priv);
+       u32 fuse, eu_dis;
+
+       fuse = I915_READ(CHV_FUSE_GT);
+
+       info->slice_total = 1;
+
+       if (!(fuse & CHV_FGT_DISABLE_SS0)) {
+               info->subslice_per_slice++;
+               eu_dis = fuse & (CHV_FGT_EU_DIS_SS0_R0_MASK |
+                                CHV_FGT_EU_DIS_SS0_R1_MASK);
+               info->eu_total += 8 - hweight32(eu_dis);
+       }
+
+       if (!(fuse & CHV_FGT_DISABLE_SS1)) {
+               info->subslice_per_slice++;
+               eu_dis = fuse & (CHV_FGT_EU_DIS_SS1_R0_MASK |
+                                CHV_FGT_EU_DIS_SS1_R1_MASK);
+               info->eu_total += 8 - hweight32(eu_dis);
+       }
+
+       info->subslice_total = info->subslice_per_slice;
+       /*
+        * CHV expected to always have a uniform distribution of EU
+        * across subslices.
+       */
+       info->eu_per_subslice = info->subslice_total ?
+                               info->eu_total / info->subslice_total :
+                               0;
+       /*
+        * CHV supports subslice power gating on devices with more than
+        * one subslice, and supports EU power gating on devices with
+        * more than one EU pair per subslice.
+       */
+       info->has_slice_pg = 0;
+       info->has_subslice_pg = (info->subslice_total > 1);
+       info->has_eu_pg = (info->eu_per_subslice > 2);
+}
+
+static void gen9_sseu_info_init(struct drm_i915_private *dev_priv)
+{
+       struct intel_device_info *info = mkwrite_device_info(dev_priv);
+       int s_max = 3, ss_max = 4, eu_max = 8;
+       int s, ss;
+       u32 fuse2, s_enable, ss_disable, eu_disable;
+       u8 eu_mask = 0xff;
+
+       fuse2 = I915_READ(GEN8_FUSE2);
+       s_enable = (fuse2 & GEN8_F2_S_ENA_MASK) >> GEN8_F2_S_ENA_SHIFT;
+       ss_disable = (fuse2 & GEN9_F2_SS_DIS_MASK) >> GEN9_F2_SS_DIS_SHIFT;
+
+       info->slice_total = hweight32(s_enable);
+       /*
+        * The subslice disable field is global, i.e. it applies
+        * to each of the enabled slices.
+       */
+       info->subslice_per_slice = ss_max - hweight32(ss_disable);
+       info->subslice_total = info->slice_total * info->subslice_per_slice;
+
+       /*
+        * Iterate through enabled slices and subslices to
+        * count the total enabled EU.
+       */
+       for (s = 0; s < s_max; s++) {
+               if (!(s_enable & BIT(s)))
+                       /* skip disabled slice */
+                       continue;
+
+               eu_disable = I915_READ(GEN9_EU_DISABLE(s));
+               for (ss = 0; ss < ss_max; ss++) {
+                       int eu_per_ss;
+
+                       if (ss_disable & BIT(ss))
+                               /* skip disabled subslice */
+                               continue;
+
+                       eu_per_ss = eu_max - hweight8((eu_disable >> (ss*8)) &
+                                                     eu_mask);
+
+                       /*
+                        * Record which subslice(s) has(have) 7 EUs. we
+                        * can tune the hash used to spread work among
+                        * subslices if they are unbalanced.
+                        */
+                       if (eu_per_ss == 7)
+                               info->subslice_7eu[s] |= BIT(ss);
+
+                       info->eu_total += eu_per_ss;
+               }
+       }
+
+       /*
+        * SKL is expected to always have a uniform distribution
+        * of EU across subslices with the exception that any one
+        * EU in any one subslice may be fused off for die
+        * recovery. BXT is expected to be perfectly uniform in EU
+        * distribution.
+       */
+       info->eu_per_subslice = info->subslice_total ?
+                               DIV_ROUND_UP(info->eu_total,
+                                            info->subslice_total) : 0;
+       /*
+        * SKL supports slice power gating on devices with more than
+        * one slice, and supports EU power gating on devices with
+        * more than one EU pair per subslice. BXT supports subslice
+        * power gating on devices with more than one subslice, and
+        * supports EU power gating on devices with more than one EU
+        * pair per subslice.
+       */
+       info->has_slice_pg =
+               (IS_SKYLAKE(dev_priv) || IS_KABYLAKE(dev_priv)) &&
+               info->slice_total > 1;
+       info->has_subslice_pg =
+               IS_BROXTON(dev_priv) && info->subslice_total > 1;
+       info->has_eu_pg = info->eu_per_subslice > 2;
+
+       if (IS_BROXTON(dev_priv)) {
+#define IS_SS_DISABLED(_ss_disable, ss)    (_ss_disable & BIT(ss))
+               /*
+                * There is a HW issue in 2x6 fused down parts that requires
+                * Pooled EU to be enabled as a WA. The pool configuration
+                * changes depending upon which subslice is fused down. This
+                * doesn't affect if the device has all 3 subslices enabled.
+                */
+               /* WaEnablePooledEuFor2x6:bxt */
+               info->has_pooled_eu = ((info->subslice_per_slice == 3) ||
+                                      (info->subslice_per_slice == 2 &&
+                                       INTEL_REVID(dev_priv) < BXT_REVID_C0));
+
+               info->min_eu_in_pool = 0;
+               if (info->has_pooled_eu) {
+                       if (IS_SS_DISABLED(ss_disable, 0) ||
+                           IS_SS_DISABLED(ss_disable, 2))
+                               info->min_eu_in_pool = 3;
+                       else if (IS_SS_DISABLED(ss_disable, 1))
+                               info->min_eu_in_pool = 6;
+                       else
+                               info->min_eu_in_pool = 9;
+               }
+#undef IS_SS_DISABLED
+       }
+}
+
+static void broadwell_sseu_info_init(struct drm_i915_private *dev_priv)
+{
+       struct intel_device_info *info = mkwrite_device_info(dev_priv);
+       const int s_max = 3, ss_max = 3, eu_max = 8;
+       int s, ss;
+       u32 fuse2, eu_disable[s_max], s_enable, ss_disable;
+
+       fuse2 = I915_READ(GEN8_FUSE2);
+       s_enable = (fuse2 & GEN8_F2_S_ENA_MASK) >> GEN8_F2_S_ENA_SHIFT;
+       ss_disable = (fuse2 & GEN8_F2_SS_DIS_MASK) >> GEN8_F2_SS_DIS_SHIFT;
+
+       eu_disable[0] = I915_READ(GEN8_EU_DISABLE0) & GEN8_EU_DIS0_S0_MASK;
+       eu_disable[1] = (I915_READ(GEN8_EU_DISABLE0) >> GEN8_EU_DIS0_S1_SHIFT) |
+                       ((I915_READ(GEN8_EU_DISABLE1) & GEN8_EU_DIS1_S1_MASK) <<
+                        (32 - GEN8_EU_DIS0_S1_SHIFT));
+       eu_disable[2] = (I915_READ(GEN8_EU_DISABLE1) >> GEN8_EU_DIS1_S2_SHIFT) |
+                       ((I915_READ(GEN8_EU_DISABLE2) & GEN8_EU_DIS2_S2_MASK) <<
+                        (32 - GEN8_EU_DIS1_S2_SHIFT));
+
+       info->slice_total = hweight32(s_enable);
+
+       /*
+        * The subslice disable field is global, i.e. it applies
+        * to each of the enabled slices.
+        */
+       info->subslice_per_slice = ss_max - hweight32(ss_disable);
+       info->subslice_total = info->slice_total * info->subslice_per_slice;
+
+       /*
+        * Iterate through enabled slices and subslices to
+        * count the total enabled EU.
+        */
+       for (s = 0; s < s_max; s++) {
+               if (!(s_enable & (0x1 << s)))
+                       /* skip disabled slice */
+                       continue;
+
+               for (ss = 0; ss < ss_max; ss++) {
+                       u32 n_disabled;
+
+                       if (ss_disable & (0x1 << ss))
+                               /* skip disabled subslice */
+                               continue;
+
+                       n_disabled = hweight8(eu_disable[s] >> (ss * eu_max));
+
+                       /*
+                        * Record which subslices have 7 EUs.
+                        */
+                       if (eu_max - n_disabled == 7)
+                               info->subslice_7eu[s] |= 1 << ss;
+
+                       info->eu_total += eu_max - n_disabled;
+               }
+       }
+
+       /*
+        * BDW is expected to always have a uniform distribution of EU across
+        * subslices with the exception that any one EU in any one subslice may
+        * be fused off for die recovery.
+        */
+       info->eu_per_subslice = info->subslice_total ?
+               DIV_ROUND_UP(info->eu_total, info->subslice_total) : 0;
+
+       /*
+        * BDW supports slice power gating on devices with more than
+        * one slice.
+        */
+       info->has_slice_pg = (info->slice_total > 1);
+       info->has_subslice_pg = 0;
+       info->has_eu_pg = 0;
+}
+
+/*
+ * Determine various intel_device_info fields at runtime.
+ *
+ * Use it when either:
+ *   - it's judged too laborious to fill n static structures with the limit
+ *     when a simple if statement does the job,
+ *   - run-time checks (eg read fuse/strap registers) are needed.
+ *
+ * This function needs to be called:
+ *   - after the MMIO has been setup as we are reading registers,
+ *   - after the PCH has been detected,
+ *   - before the first usage of the fields it can tweak.
+ */
+void intel_device_info_runtime_init(struct drm_i915_private *dev_priv)
+{
+       struct intel_device_info *info = mkwrite_device_info(dev_priv);
+       enum pipe pipe;
+
+       /*
+        * Skylake and Broxton currently don't expose the topmost plane as its
+        * use is exclusive with the legacy cursor and we only want to expose
+        * one of those, not both. Until we can safely expose the topmost plane
+        * as a DRM_PLANE_TYPE_CURSOR with all the features exposed/supported,
+        * we don't expose the topmost plane at all to prevent ABI breakage
+        * down the line.
+        */
+       if (IS_BROXTON(dev_priv)) {
+               info->num_sprites[PIPE_A] = 2;
+               info->num_sprites[PIPE_B] = 2;
+               info->num_sprites[PIPE_C] = 1;
+       } else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
+               for_each_pipe(dev_priv, pipe)
+                       info->num_sprites[pipe] = 2;
+       else
+               for_each_pipe(dev_priv, pipe)
+                       info->num_sprites[pipe] = 1;
+
+       if (i915.disable_display) {
+               DRM_INFO("Display disabled (module parameter)\n");
+               info->num_pipes = 0;
+       } else if (info->num_pipes > 0 &&
+                  (IS_GEN7(dev_priv) || IS_GEN8(dev_priv)) &&
+                  HAS_PCH_SPLIT(dev_priv)) {
+               u32 fuse_strap = I915_READ(FUSE_STRAP);
+               u32 sfuse_strap = I915_READ(SFUSE_STRAP);
+
+               /*
+                * SFUSE_STRAP is supposed to have a bit signalling the display
+                * is fused off. Unfortunately it seems that, at least in
+                * certain cases, fused off display means that PCH display
+                * reads don't land anywhere. In that case, we read 0s.
+                *
+                * On CPT/PPT, we can detect this case as SFUSE_STRAP_FUSE_LOCK
+                * should be set when taking over after the firmware.
+                */
+               if (fuse_strap & ILK_INTERNAL_DISPLAY_DISABLE ||
+                   sfuse_strap & SFUSE_STRAP_DISPLAY_DISABLED ||
+                   (dev_priv->pch_type == PCH_CPT &&
+                    !(sfuse_strap & SFUSE_STRAP_FUSE_LOCK))) {
+                       DRM_INFO("Display fused off, disabling\n");
+                       info->num_pipes = 0;
+               } else if (fuse_strap & IVB_PIPE_C_DISABLE) {
+                       DRM_INFO("PipeC fused off\n");
+                       info->num_pipes -= 1;
+               }
+       } else if (info->num_pipes > 0 && IS_GEN9(dev_priv)) {
+               u32 dfsm = I915_READ(SKL_DFSM);
+               u8 disabled_mask = 0;
+               bool invalid;
+               int num_bits;
+
+               if (dfsm & SKL_DFSM_PIPE_A_DISABLE)
+                       disabled_mask |= BIT(PIPE_A);
+               if (dfsm & SKL_DFSM_PIPE_B_DISABLE)
+                       disabled_mask |= BIT(PIPE_B);
+               if (dfsm & SKL_DFSM_PIPE_C_DISABLE)
+                       disabled_mask |= BIT(PIPE_C);
+
+               num_bits = hweight8(disabled_mask);
+
+               switch (disabled_mask) {
+               case BIT(PIPE_A):
+               case BIT(PIPE_B):
+               case BIT(PIPE_A) | BIT(PIPE_B):
+               case BIT(PIPE_A) | BIT(PIPE_C):
+                       invalid = true;
+                       break;
+               default:
+                       invalid = false;
+               }
+
+               if (num_bits > info->num_pipes || invalid)
+                       DRM_ERROR("invalid pipe fuse configuration: 0x%x\n",
+                                 disabled_mask);
+               else
+                       info->num_pipes -= num_bits;
+       }
+
+       /* Initialize slice/subslice/EU info */
+       if (IS_CHERRYVIEW(dev_priv))
+               cherryview_sseu_info_init(dev_priv);
+       else if (IS_BROADWELL(dev_priv))
+               broadwell_sseu_info_init(dev_priv);
+       else if (INTEL_INFO(dev_priv)->gen >= 9)
+               gen9_sseu_info_init(dev_priv);
+
+       info->has_snoop = !info->has_llc;
+
+       /* Snooping is broken on BXT A stepping. */
+       if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1))
+               info->has_snoop = false;
+
+       DRM_DEBUG_DRIVER("slice total: %u\n", info->slice_total);
+       DRM_DEBUG_DRIVER("subslice total: %u\n", info->subslice_total);
+       DRM_DEBUG_DRIVER("subslice per slice: %u\n", info->subslice_per_slice);
+       DRM_DEBUG_DRIVER("EU total: %u\n", info->eu_total);
+       DRM_DEBUG_DRIVER("EU per subslice: %u\n", info->eu_per_subslice);
+       DRM_DEBUG_DRIVER("has slice power gating: %s\n",
+                        info->has_slice_pg ? "y" : "n");
+       DRM_DEBUG_DRIVER("has subslice power gating: %s\n",
+                        info->has_subslice_pg ? "y" : "n");
+       DRM_DEBUG_DRIVER("has EU power gating: %s\n",
+                        info->has_eu_pg ? "y" : "n");
+}