drm/i915: Handle all MCR ranges

The bspec documents multiple MCR ranges; make sure they're all captured
by the driver.

Bspec: 13991, 52079
Fixes: 592a7c5e08 ("drm/i915: Extend non readable mcr range")
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311162300.1838847-2-matthew.d.roper@intel.com
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>

drivers/gpu/drm/i915/gt/intel_workarounds.c

@@ -1648,15 +1648,34 @@ err_obj:
 	return ERR_PTR(err);
 }
 
+static const struct {
+	u32 start;
+	u32 end;
+} mcr_ranges_gen8[] = {
+	{ .start = 0x5500, .end = 0x55ff },
+	{ .start = 0x7000, .end = 0x7fff },
+	{ .start = 0x9400, .end = 0x97ff },
+	{ .start = 0xb000, .end = 0xb3ff },
+	{ .start = 0xe000, .end = 0xe7ff },
+	{},
+};
+
 static bool mcr_range(struct drm_i915_private *i915, u32 offset)
 {
+	int i;
+
+	if (INTEL_GEN(i915) < 8)
+		return false;
+
 	/*
-	 * Registers in this range are affected by the MCR selector
+	 * Registers in these ranges are affected by the MCR selector
 	 * which only controls CPU initiated MMIO. Routing does not
 	 * work for CS access so we cannot verify them on this path.
 	 */
-	if (INTEL_GEN(i915) >= 8 && (offset >= 0xb000 && offset <= 0xb4ff))
-		return true;
+	for (i = 0; mcr_ranges_gen8[i].start; i++)
+		if (offset >= mcr_ranges_gen8[i].start &&
+		    offset <= mcr_ranges_gen8[i].end)
+			return true;
 
 	return false;
 }