drm/i915: Check workaround status on dfs read time

As the workaround list has the value as initialization time
constant, we can do the simple checking on the go without
negleting igt.

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -2657,16 +2657,16 @@ static int i915_wa_registers(struct seq_file *m, void *unused)
 
 	seq_printf(m, "Workarounds applied: %d\n", dev_priv->workarounds.count);
 	for (i = 0; i < dev_priv->workarounds.count; ++i) {
-		u32 addr, mask;
+		u32 addr, mask, value, read;
+		bool ok;
 
 		addr = dev_priv->workarounds.reg[i].addr;
 		mask = dev_priv->workarounds.reg[i].mask;
-		dev_priv->workarounds.reg[i].value = I915_READ(addr) | mask;
-		if (dev_priv->workarounds.reg[i].addr)
-			seq_printf(m, "0x%X: 0x%08X, mask: 0x%08X\n",
-				   dev_priv->workarounds.reg[i].addr,
-				   dev_priv->workarounds.reg[i].value,
-				   dev_priv->workarounds.reg[i].mask);
+		value = dev_priv->workarounds.reg[i].value;
+		read = I915_READ(addr);
+		ok = (value & mask) == (read & mask);
+		seq_printf(m, "0x%X: 0x%08X, mask: 0x%08X, read: 0x%08x, status: %s\n",
+			   addr, value, mask, read, ok ? "OK" : "FAIL");
 	}
 
 	intel_runtime_pm_put(dev_priv);