Revert "drm/amdgpu: add drm buddy support to amdgpu"

This reverts commit c9cad93.

This is part of a revert of the following commits:
commit 708d19d ("drm/amdgpu: move internal vram_mgr function into the C file")
commit 5e3f1e7 ("drm/amdgpu: fix start calculation in amdgpu_vram_mgr_new")
commit c9cad93 ("drm/amdgpu: add drm buddy support to amdgpu")

[WHY]
Few users reported garbaged graphics as soon as x starts,
reverting until this can be resolved.

Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220708093047.492662-3-Arunpravin.PaneerSelvam@amd.com
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>

Author: arunpravin24

drivers/gpu/drm/Kconfig

@@ -256,7 +256,6 @@ config DRM_AMDGPU
 	select HWMON
 	select BACKLIGHT_CLASS_DEVICE
 	select INTERVAL_TREE
-	select DRM_BUDDY
 	help
 	  Choose this option if you have a recent AMD Radeon graphics card.
 

drivers/gpu/drm/amd/amdgpu/amdgpu_res_cursor.h

@@ -30,15 +30,12 @@
 #include <drm/ttm/ttm_resource.h>
 #include <drm/ttm/ttm_range_manager.h>
 
-#include "amdgpu_vram_mgr.h"
-
 /* state back for walking over vram_mgr and gtt_mgr allocations */
 struct amdgpu_res_cursor {
 	uint64_t		start;
 	uint64_t		size;
 	uint64_t		remaining;
-	void			*node;
-	uint32_t		mem_type;
+	struct drm_mm_node	*node;
 };
 
 /**
@@ -55,63 +52,27 @@ static inline void amdgpu_res_first(struct ttm_resource *res,
 				    uint64_t start, uint64_t size,
 				    struct amdgpu_res_cursor *cur)
 {
-	struct drm_buddy_block *block;
-	struct list_head *head, *next;
 	struct drm_mm_node *node;
 
-	if (!res)
-		goto fallback;
-
-	BUG_ON(start + size > res->num_pages << PAGE_SHIFT);
-
-	cur->mem_type = res->mem_type;
-
-	switch (cur->mem_type) {
-	case TTM_PL_VRAM:
-		head = &to_amdgpu_vram_mgr_resource(res)->blocks;
-
-		block = list_first_entry_or_null(head,
-						 struct drm_buddy_block,
-						 link);
-		if (!block)
-			goto fallback;
-
-		while (start >= amdgpu_vram_mgr_block_size(block)) {
-			start -= amdgpu_vram_mgr_block_size(block);
-
-			next = block->link.next;
-			if (next != head)
-				block = list_entry(next, struct drm_buddy_block, link);
-		}
-
-		cur->start = amdgpu_vram_mgr_block_start(block) + start;
-		cur->size = min(amdgpu_vram_mgr_block_size(block) - start, size);
-		cur->remaining = size;
-		cur->node = block;
-		break;
-	case TTM_PL_TT:
-		node = to_ttm_range_mgr_node(res)->mm_nodes;
-		while (start >= node->size << PAGE_SHIFT)
-			start -= node++->size << PAGE_SHIFT;
-
-		cur->start = (node->start << PAGE_SHIFT) + start;
-		cur->size = min((node->size << PAGE_SHIFT) - start, size);
+	if (!res || res->mem_type == TTM_PL_SYSTEM) {
+		cur->start = start;
+		cur->size = size;
 		cur->remaining = size;
-		cur->node = node;
-		break;
-	default:
-		goto fallback;
+		cur->node = NULL;
+		WARN_ON(res && start + size > res->num_pages << PAGE_SHIFT);
+		return;
 	}
 
-	return;
+	BUG_ON(start + size > res->num_pages << PAGE_SHIFT);
 
-fallback:
-	cur->start = start;
-	cur->size = size;
+	node = to_ttm_range_mgr_node(res)->mm_nodes;
+	while (start >= node->size << PAGE_SHIFT)
+		start -= node++->size << PAGE_SHIFT;
+
+	cur->start = (node->start << PAGE_SHIFT) + start;
+	cur->size = min((node->size << PAGE_SHIFT) - start, size);
 	cur->remaining = size;
-	cur->node = NULL;
-	WARN_ON(res && start + size > res->num_pages << PAGE_SHIFT);
-	return;
+	cur->node = node;
 }
 
 /**
@@ -124,9 +85,7 @@ static inline void amdgpu_res_first(struct ttm_resource *res,
  */
 static inline void amdgpu_res_next(struct amdgpu_res_cursor *cur, uint64_t size)
 {
-	struct drm_buddy_block *block;
-	struct drm_mm_node *node;
-	struct list_head *next;
+	struct drm_mm_node *node = cur->node;
 
 	BUG_ON(size > cur->remaining);
 
@@ -140,27 +99,9 @@ static inline void amdgpu_res_next(struct amdgpu_res_cursor *cur, uint64_t size)
 		return;
 	}
 
-	switch (cur->mem_type) {
-	case TTM_PL_VRAM:
-		block = cur->node;
-
-		next = block->link.next;
-		block = list_entry(next, struct drm_buddy_block, link);
-
-		cur->node = block;
-		cur->start = amdgpu_vram_mgr_block_start(block);
-		cur->size = min(amdgpu_vram_mgr_block_size(block), cur->remaining);
-		break;
-	case TTM_PL_TT:
-		node = cur->node;
-
-		cur->node = ++node;
-		cur->start = node->start << PAGE_SHIFT;
-		cur->size = min(node->size << PAGE_SHIFT, cur->remaining);
-		break;
-	default:
-		return;
-	}
+	cur->node = ++node;
+	cur->start = node->start << PAGE_SHIFT;
+	cur->size = min(node->size << PAGE_SHIFT, cur->remaining);
 }
 
 #endif

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h

@@ -26,7 +26,6 @@
 
 #include <linux/dma-direction.h>
 #include <drm/gpu_scheduler.h>
-#include "amdgpu_vram_mgr.h"
 #include "amdgpu.h"
 
 #define AMDGPU_PL_GDS		(TTM_PL_PRIV + 0)
@@ -39,6 +38,15 @@
 
 #define AMDGPU_POISON	0xd0bed0be
 
+struct amdgpu_vram_mgr {
+	struct ttm_resource_manager manager;
+	struct drm_mm mm;
+	spinlock_t lock;
+	struct list_head reservations_pending;
+	struct list_head reserved_pages;
+	atomic64_t vis_usage;
+};
+
 struct amdgpu_gtt_mgr {
 	struct ttm_resource_manager manager;
 	struct drm_mm mm;