From aacf88d119caa4af802ef533203758c1f519a831 Mon Sep 17 00:00:00 2001
From: Lucas De Marchi <lucas.demarchi@intel.com>
Date: Thu, 2 Jul 2020 13:07:14 -0700
Subject: drm/i915: do not read swizzle info if unavailable
Git-commit: 1fe541ccef9ffaf654a29d1bfd9206a2c350d11b
Patch-mainline: v5.9-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322

Since gen8 we don't use swizzle anymore. Don't dump registers related to
it: registers may or may not be there.

v2: pull the rest of driver state reporting before the read out (Chris)

Cc: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
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/20200702200714.1278-1-lucas.demarchi@intel.com
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 9ca94a435b75..94ed442910d6 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1138,13 +1138,20 @@ static int i915_swizzle_info(struct seq_file *m, void *data)
 	struct intel_uncore *uncore = &dev_priv->uncore;
 	intel_wakeref_t wakeref;
 
-	wakeref = intel_runtime_pm_get(&dev_priv->runtime_pm);
-
 	seq_printf(m, "bit6 swizzle for X-tiling = %s\n",
 		   swizzle_string(dev_priv->ggtt.bit_6_swizzle_x));
 	seq_printf(m, "bit6 swizzle for Y-tiling = %s\n",
 		   swizzle_string(dev_priv->ggtt.bit_6_swizzle_y));
 
+	if (dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES)
+		seq_puts(m, "L-shaped memory detected\n");
+
+	/* On BDW+, swizzling is not used. See detect_bit_6_swizzle() */
+	if (INTEL_GEN(dev_priv) >= 8 || IS_VALLEYVIEW(dev_priv))
+		return 0;
+
+	wakeref = intel_runtime_pm_get(&dev_priv->runtime_pm);
+
 	if (IS_GEN_RANGE(dev_priv, 3, 4)) {
 		seq_printf(m, "DDC = 0x%08x\n",
 			   intel_uncore_read(uncore, DCC));
@@ -1173,9 +1180,6 @@ static int i915_swizzle_info(struct seq_file *m, void *data)
 			   intel_uncore_read(uncore, DISP_ARB_CTL));
 	}
 
-	if (dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES)
-		seq_puts(m, "L-shaped memory detected\n");
-
 	intel_runtime_pm_put(&dev_priv->runtime_pm, wakeref);
 
 	return 0;
-- 
2.29.2