drm/i915: Store and use edram capabilities

Store the edram capabilities instead of only the size of
edram. This is preparatory patch to allow edram size calculation
based on edram capability bits for gen9+. With gen9 the
edram is behind llc and is a separate entity. With hsw/bdw
it was more of a victim cache for LLC so the name 'eLLC' might
be warranted. Regardless, rename all mentions of eLLC to EDRAM to
clear the confusion.

v2: return bytes for edram size (Chris)
    s/eLLC/eDRAM in output if we are gen > 8

v3: rebase, INTEL_GEN (Chris)
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -2404,10 +2404,11 @@ static int i915_llc(struct seq_file *m, void *data)
 	struct drm_info_node *node = m->private;
 	struct drm_device *dev = node->minor->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	const bool edram = INTEL_GEN(dev_priv) > 8;
 
-	/* Size calculation for LLC is a bit of a pain. Ignore for now. */
 	seq_printf(m, "LLC: %s\n", yesno(HAS_LLC(dev)));
-	seq_printf(m, "eLLC: %zuMB\n", dev_priv->ellc_size);
+	seq_printf(m, "%s: %lluMB\n", edram ? "eDRAM" : "eLLC",
+		   intel_uncore_edram_size(dev_priv)/1024/1024);
 
 	return 0;
 }

drivers/gpu/drm/i915/i915_drv.h

@@ -1873,7 +1873,7 @@ struct drm_i915_private {
 	struct intel_l3_parity l3_parity;
 
 	/* Cannot be determined by PCIID. You must always read a register. */
-	size_t ellc_size;
+	u32 edram_cap;
 
 	/* gen6+ rps state */
 	struct intel_gen6_power_mgmt rps;
@@ -2624,8 +2624,9 @@ struct drm_i915_cmd_table {
 #define HAS_VEBOX(dev)		(INTEL_INFO(dev)->ring_mask & VEBOX_RING)
 #define HAS_LLC(dev)		(INTEL_INFO(dev)->has_llc)
 #define HAS_SNOOP(dev)		(INTEL_INFO(dev)->has_snoop)
+#define HAS_EDRAM(dev)		(__I915__(dev)->edram_cap & EDRAM_ENABLED)
 #define HAS_WT(dev)		((IS_HASWELL(dev) || IS_BROADWELL(dev)) && \
-				 __I915__(dev)->ellc_size)
+				 HAS_EDRAM(dev))
 #define I915_NEED_GFX_HWS(dev)	(INTEL_INFO(dev)->need_gfx_hws)
 
 #define HAS_HW_CONTEXTS(dev)	(INTEL_INFO(dev)->gen >= 6)
@@ -2803,6 +2804,8 @@ void intel_uncore_forcewake_get__locked(struct drm_i915_private *dev_priv,
 					enum forcewake_domains domains);
 void intel_uncore_forcewake_put__locked(struct drm_i915_private *dev_priv,
 					enum forcewake_domains domains);
+u64 intel_uncore_edram_size(struct drm_i915_private *dev_priv);
+
 void assert_forcewakes_inactive(struct drm_i915_private *dev_priv);
 static inline bool intel_vgpu_active(struct drm_device *dev)
 {

drivers/gpu/drm/i915/i915_gem.c

@@ -4892,7 +4892,7 @@ i915_gem_init_hw(struct drm_device *dev)
 	/* Double layer security blanket, see i915_gem_init() */
 	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
 
-	if (dev_priv->ellc_size && INTEL_GEN(dev_priv) < 9)
+	if (HAS_EDRAM(dev) && INTEL_GEN(dev_priv) < 9)
 		I915_WRITE(HSW_IDICR, I915_READ(HSW_IDICR) | IDIHASHMSK(0xf));
 
 	if (IS_HASWELL(dev))

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -3172,7 +3172,8 @@ int i915_ggtt_init_hw(struct drm_device *dev)
 	} else if (INTEL_INFO(dev)->gen < 8) {
 		ggtt->probe = gen6_gmch_probe;
 		ggtt->base.cleanup = gen6_gmch_remove;
-		if (IS_HASWELL(dev) && dev_priv->ellc_size)
+
+		if (HAS_EDRAM(dev))
 			ggtt->base.pte_encode = iris_pte_encode;
 		else if (IS_HASWELL(dev))
 			ggtt->base.pte_encode = hsw_pte_encode;

drivers/gpu/drm/i915/i915_reg.h

@@ -6882,7 +6882,7 @@ enum skl_disp_power_wells {
 
 #define  HSW_IDICR				_MMIO(0x9008)
 #define    IDIHASHMSK(x)			(((x) & 0x3f) << 16)
-#define  HSW_EDRAM_PRESENT			_MMIO(0x120010)
+#define  HSW_EDRAM_CAP				_MMIO(0x120010)
 #define    EDRAM_ENABLED			0x1
 
 #define GEN6_UCGCTL1				_MMIO(0x9400)

drivers/gpu/drm/i915/intel_uncore.c

@@ -315,21 +315,36 @@ void intel_uncore_forcewake_reset(struct drm_device *dev, bool restore)
 	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 }
 
-static void intel_uncore_ellc_detect(struct drm_device *dev)
+u64 intel_uncore_edram_size(struct drm_i915_private *dev_priv)
 {
-	struct drm_i915_private *dev_priv = dev->dev_private;
+	if (!HAS_EDRAM(dev_priv))
+		return 0;
+
+	/* The docs do not explain exactly how the calculation can be
+	 * made. It is somewhat guessable, but for now, it's always
+	 * 128MB.
+	 */
+
+	return 128 * 1024 * 1024;
+}
+
+static void intel_uncore_edram_detect(struct drm_i915_private *dev_priv)
+{
+	if (IS_HASWELL(dev_priv) ||
+	    IS_BROADWELL(dev_priv) ||
+	    INTEL_GEN(dev_priv) >= 9) {
+		dev_priv->edram_cap = __raw_i915_read32(dev_priv,
+							HSW_EDRAM_CAP);
 
-	if ((IS_HASWELL(dev) || IS_BROADWELL(dev) ||
-	     INTEL_INFO(dev)->gen >= 9) &&
-	    (__raw_i915_read32(dev_priv, HSW_EDRAM_PRESENT) & EDRAM_ENABLED)) {
-		/* The docs do not explain exactly how the calculation can be
-		 * made. It is somewhat guessable, but for now, it's always
-		 * 128MB.
-		 * NB: We can't write IDICR yet because we do not have gt funcs
+		/* NB: We can't write IDICR yet because we do not have gt funcs
 		 * set up */
-		dev_priv->ellc_size = 128;
-		DRM_INFO("Found %zuMB of eLLC\n", dev_priv->ellc_size);
+	} else {
+		dev_priv->edram_cap = 0;
 	}
+
+	if (HAS_EDRAM(dev_priv))
+		DRM_INFO("Found %lluMB of eDRAM\n",
+			 intel_uncore_edram_size(dev_priv) / (1024 * 1024));
 }
 
 static bool
@@ -1301,7 +1316,7 @@ void intel_uncore_init(struct drm_device *dev)
 
 	i915_check_vgpu(dev);
 
-	intel_uncore_ellc_detect(dev);
+	intel_uncore_edram_detect(dev_priv);
 	intel_uncore_fw_domains_init(dev);
 	__intel_uncore_early_sanitize(dev, false);