drm/i915: do not read swizzle info if unavailable

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

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 9ca94a4..94ed442 100644 (file)
--- 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;