drm/i915/debugfs: add rcs topology entry

While the end goal is to make this information available to userspace
through a new ioctl, there is no reason we can't display it in a human
readable fashion through debugfs.

slice0: 3 subslice(s) (0x7):
	subslice0: 8 EUs (0xff)
	subslice1: 8 EUs (0xff)
	subslice2: 8 EUs (0xff)
	subslice3: 0 EUs (0x0)
slice1: 3 subslice(s) (0x7):
	subslice0: 8 EUs (0xff)
	subslice1: 8 EUs (0xff)
	subslice2: 8 EUs (0xff)
	subslice3: 0 EUs (0x0)
slice2: 3 subslice(s) (0x7):
	subslice0: 8 EUs (0xff)
	subslice1: 8 EUs (0xff)
	subslice2: 8 EUs (0xff)
	subslice3: 0 EUs (0x0)

v2: Reformat debugfs printing (Tvrtko)
    Use the new EU mask helper (Tvrtko)

v3: Move printing code to intel_device_info.c to be shared with error
    state (Michal)

v4: Bump u8 to u16 when using sseu_get_eus() (Lionel)

Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180306122857.27317-4-lionel.g.landwerlin@intel.com
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index bd5f98c..89f7ff2 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -3201,6 +3201,16 @@ static int i915_engine_info(struct seq_file *m, void *unused)
 	return 0;
 }
 
+static int i915_rcs_topology(struct seq_file *m, void *unused)
+{
+	struct drm_i915_private *dev_priv = node_to_i915(m->private);
+	struct drm_printer p = drm_seq_file_printer(m);
+
+	intel_device_info_dump_topology(&INTEL_INFO(dev_priv)->sseu, &p);
+
+	return 0;
+}
+
 static int i915_shrinker_info(struct seq_file *m, void *unused)
 {
 	struct drm_i915_private *i915 = node_to_i915(m->private);
@@ -4733,6 +4743,7 @@ static const struct drm_info_list i915_debugfs_list[] = {
 	{"i915_dmc_info", i915_dmc_info, 0},
 	{"i915_display_info", i915_display_info, 0},
 	{"i915_engine_info", i915_engine_info, 0},
+	{"i915_rcs_topology", i915_rcs_topology, 0},
 	{"i915_shrinker_info", i915_shrinker_info, 0},
 	{"i915_shared_dplls_info", i915_shared_dplls_info, 0},
 	{"i915_dp_mst_info", i915_dp_mst_info, 0},