From b099a4459d99fbc032b046e55ca77c8577f5a214 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
Date: Thu, 2 Nov 2017 17:17:37 +0200
Subject: [PATCH] drm/i915: Use ELK stolen memory reserved detection for ILK
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Git-commit: b099a4459d99fbc032b046e55ca77c8577f5a214
Patch-mainline: v4.16-rc1
References: FATE#322643 bsc#1055900

While I have no solid proof that ILK follows the ELK path when it
comes to the stolen memory reserved area, there are some hints that
it might be the case. Unfortunately my ILK doesn't have this enabled,
and no way to enable it via the BIOS it seems.

So let's have ILK use the ELK code path, and let's toss in a WARN
into the code to see if we catch anyone with an ILK that has this
enabled to further analyze the situation.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171102151737.23336-3-ville.syrjala@linux.intel.com
Acked-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/i915/i915_gem_stolen.c |   18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -300,6 +300,12 @@ static void g4x_get_stolen_reserved(stru
 		return;
 	}
 
+	/*
+	 * Whether ILK really reuses the ELK register for this is unclear.
+	 * Let's see if we catch anyone with this supposedly enabled on ILK.
+	 */
+	WARN(IS_GEN5(dev_priv), "ILK stolen reserved found? 0x%08x\n", reg_val);
+
 	*base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
 
 	WARN_ON((reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
@@ -466,14 +472,12 @@ int i915_gem_init_stolen(struct drm_i915
 	case 3:
 		break;
 	case 4:
-		if (IS_G4X(dev_priv))
-			g4x_get_stolen_reserved(dev_priv,
-						&reserved_base, &reserved_size);
-		break;
+		if (!IS_G4X(dev_priv))
+			break;
+		/* fall through */
 	case 5:
-		/* Assume the gen6 maximum for the older platforms. */
-		reserved_size = 1024 * 1024;
-		reserved_base = stolen_top - reserved_size;
+		g4x_get_stolen_reserved(dev_priv,
+					&reserved_base, &reserved_size);
 		break;
 	case 6:
 		gen6_get_stolen_reserved(dev_priv,