drm/mm: add ability to dump mm lists via debugfs

This adds code to the drm_mm to talk to debugfs, and adds
support to radeon to add the VRAM and GTT mm lists to debugfs.

I tested with spinlock debugging and it doesn't give out.
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/drm_mm.c

@@ -44,6 +44,7 @@
 #include "drmP.h"
 #include "drm_mm.h"
 #include <linux/slab.h>
+#include <linux/seq_file.h>
 
 #define MM_UNUSED_TARGET 4
 
@@ -370,3 +371,23 @@ void drm_mm_takedown(struct drm_mm * mm)
 	BUG_ON(mm->num_unused != 0);
 }
 EXPORT_SYMBOL(drm_mm_takedown);
+
+#if defined(CONFIG_DEBUG_FS)
+int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm)
+{
+	struct drm_mm_node *entry;
+	int total_used = 0, total_free = 0, total = 0;
+
+	list_for_each_entry(entry, &mm->ml_entry, ml_entry) {
+		seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: %s\n", entry->start, entry->start + entry->size, entry->size, entry->free ? "free" : "used");
+		total += entry->size;
+		if (entry->free)
+			total_free += entry->size;
+		else
+			total_used += entry->size;
+	}
+	seq_printf(m, "total: %d, used %d free %d\n", total, total_free, total_used);
+	return 0;
+}
+EXPORT_SYMBOL(drm_mm_dump_table);
+#endif

drivers/gpu/drm/radeon/radeon_ttm.c

@@ -35,11 +35,14 @@
 #include <ttm/ttm_module.h>
 #include <drm/drmP.h>
 #include <drm/radeon_drm.h>
+#include <linux/seq_file.h>
 #include "radeon_reg.h"
 #include "radeon.h"
 
 #define DRM_FILE_PAGE_OFFSET (0x100000000ULL >> PAGE_SHIFT)
 
+static int radeon_ttm_debugfs_init(struct radeon_device *rdev);
+
 static struct radeon_device *radeon_get_rdev(struct ttm_bo_device *bdev)
 {
 	struct radeon_mman *mman;
@@ -504,6 +507,12 @@ int radeon_ttm_init(struct radeon_device *rdev)
 	if (unlikely(rdev->mman.bdev.dev_mapping == NULL)) {
 		rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping;
 	}
+
+	r = radeon_ttm_debugfs_init(rdev);
+	if (r) {
+		DRM_ERROR("Failed to init debugfs\n");
+		return r;
+	}
 	return 0;
 }
 
@@ -678,3 +687,50 @@ struct ttm_backend *radeon_ttm_backend_create(struct radeon_device *rdev)
 	gtt->bound = false;
 	return &gtt->backend;
 }
+
+#define RADEON_DEBUGFS_MEM_TYPES 2
+
+static struct drm_info_list radeon_mem_types_list[RADEON_DEBUGFS_MEM_TYPES];
+static char radeon_mem_types_names[RADEON_DEBUGFS_MEM_TYPES][32];
+
+#if defined(CONFIG_DEBUG_FS)
+static int radeon_mm_dump_table(struct seq_file *m, void *data)
+{
+	struct drm_info_node *node = (struct drm_info_node *)m->private;
+	struct drm_mm *mm = (struct drm_mm *)node->info_ent->data;
+	struct drm_device *dev = node->minor->dev;
+	struct radeon_device *rdev = dev->dev_private;
+	int ret;
+	struct ttm_bo_global *glob = rdev->mman.bdev.glob;
+
+	spin_lock(&glob->lru_lock);
+	ret = drm_mm_dump_table(m, mm);
+	spin_unlock(&glob->lru_lock);
+	return ret;
+}
+#endif
+
+static int radeon_ttm_debugfs_init(struct radeon_device *rdev)
+{
+	unsigned i;
+
+#if defined(CONFIG_DEBUG_FS)
+	for (i = 0; i < RADEON_DEBUGFS_MEM_TYPES; i++) {
+		if (i == 0)
+			sprintf(radeon_mem_types_names[i], "radeon_vram_mm");
+		else
+			sprintf(radeon_mem_types_names[i], "radeon_gtt_mm");
+		radeon_mem_types_list[i].name = radeon_mem_types_names[i];
+		radeon_mem_types_list[i].show = &radeon_mm_dump_table;
+		radeon_mem_types_list[i].driver_features = 0;
+		if (i == 0)
+			radeon_mem_types_list[i].data = &rdev->mman.bdev.man[TTM_PL_VRAM].manager;
+		else
+			radeon_mem_types_list[i].data = &rdev->mman.bdev.man[TTM_PL_TT].manager;
+
+	}
+	return radeon_debugfs_add_files(rdev, radeon_mem_types_list, RADEON_DEBUGFS_MEM_TYPES);
+
+#endif
+	return 0;
+}

include/drm/drm_mm.h

@@ -96,4 +96,8 @@ static inline struct drm_mm *drm_get_mm(struct drm_mm_node *block)
 	return block->mm;
 }
 
+#ifdef CONFIG_DEBUG_FS
+int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm);
+#endif
+
 #endif