1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2021 Intel Corporation 4 */ 5 #include <drm/ttm/ttm_bo_driver.h> 6 #include <drm/ttm/ttm_device.h> 7 #include <drm/ttm/ttm_range_manager.h> 8 9 #include "i915_drv.h" 10 #include "i915_scatterlist.h" 11 12 #include "intel_region_ttm.h" 13 14 /** 15 * DOC: TTM support structure 16 * 17 * The code in this file deals with setting up memory managers for TTM 18 * LMEM and MOCK regions and converting the output from 19 * the managers to struct sg_table, Basically providing the mapping from 20 * i915 GEM regions to TTM memory types and resource managers. 21 */ 22 23 /* A Zero-initialized driver for now. We don't have a TTM backend yet. */ 24 static struct ttm_device_funcs i915_ttm_bo_driver; 25 26 /** 27 * intel_region_ttm_device_init - Initialize a TTM device 28 * @dev_priv: Pointer to an i915 device private structure. 29 * 30 * Return: 0 on success, negative error code on failure. 31 */ 32 int intel_region_ttm_device_init(struct drm_i915_private *dev_priv) 33 { 34 struct drm_device *drm = &dev_priv->drm; 35 36 return ttm_device_init(&dev_priv->bdev, &i915_ttm_bo_driver, 37 drm->dev, drm->anon_inode->i_mapping, 38 drm->vma_offset_manager, false, false); 39 } 40 41 /** 42 * intel_region_ttm_device_fini - Finalize a TTM device 43 * @dev_priv: Pointer to an i915 device private structure. 44 */ 45 void intel_region_ttm_device_fini(struct drm_i915_private *dev_priv) 46 { 47 ttm_device_fini(&dev_priv->bdev); 48 } 49 50 /* 51 * Map the i915 memory regions to TTM memory types. We use the 52 * driver-private types for now, reserving TTM_PL_VRAM for stolen 53 * memory and TTM_PL_TT for GGTT use if decided to implement this. 54 */ 55 static int intel_region_to_ttm_type(struct intel_memory_region *mem) 56 { 57 int type; 58 59 GEM_BUG_ON(mem->type != INTEL_MEMORY_LOCAL && 60 mem->type != INTEL_MEMORY_MOCK); 61 62 type = mem->instance + TTM_PL_PRIV; 63 GEM_BUG_ON(type >= TTM_NUM_MEM_TYPES); 64 65 return type; 66 } 67 68 static struct ttm_resource * 69 intel_region_ttm_node_reserve(struct intel_memory_region *mem, 70 resource_size_t offset, 71 resource_size_t size) 72 { 73 struct ttm_resource_manager *man = mem->region_private; 74 struct ttm_place place = {}; 75 struct ttm_buffer_object mock_bo = {}; 76 struct ttm_resource *res; 77 int ret; 78 79 /* 80 * Having to use a mock_bo is unfortunate but stems from some 81 * drivers having private managers that insist to know what the 82 * allocate memory is intended for, using it to send private 83 * data to the manager. Also recently the bo has been used to send 84 * alignment info to the manager. Assume that apart from the latter, 85 * none of the managers we use will ever access the buffer object 86 * members, hoping we can pass the alignment info in the 87 * struct ttm_place in the future. 88 */ 89 90 place.fpfn = offset >> PAGE_SHIFT; 91 place.lpfn = place.fpfn + (size >> PAGE_SHIFT); 92 mock_bo.base.size = size; 93 ret = man->func->alloc(man, &mock_bo, &place, &res); 94 if (ret == -ENOSPC) 95 ret = -ENXIO; 96 97 return ret ? ERR_PTR(ret) : res; 98 } 99 100 /** 101 * intel_region_ttm_node_free - Free a node allocated from a resource manager 102 * @mem: The region the node was allocated from. 103 * @node: The opaque node representing an allocation. 104 */ 105 void intel_region_ttm_node_free(struct intel_memory_region *mem, 106 struct ttm_resource *res) 107 { 108 struct ttm_resource_manager *man = mem->region_private; 109 110 man->func->free(man, res); 111 } 112 113 static const struct intel_memory_region_private_ops priv_ops = { 114 .reserve = intel_region_ttm_node_reserve, 115 .free = intel_region_ttm_node_free, 116 }; 117 118 int intel_region_ttm_init(struct intel_memory_region *mem) 119 { 120 struct ttm_device *bdev = &mem->i915->bdev; 121 int mem_type = intel_region_to_ttm_type(mem); 122 int ret; 123 124 ret = ttm_range_man_init(bdev, mem_type, false, 125 resource_size(&mem->region) >> PAGE_SHIFT); 126 if (ret) 127 return ret; 128 129 mem->chunk_size = PAGE_SIZE; 130 mem->max_order = 131 get_order(rounddown_pow_of_two(resource_size(&mem->region))); 132 mem->is_range_manager = true; 133 mem->priv_ops = &priv_ops; 134 mem->region_private = ttm_manager_type(bdev, mem_type); 135 136 return 0; 137 } 138 139 /** 140 * intel_region_ttm_fini - Finalize a TTM region. 141 * @mem: The memory region 142 * 143 * This functions takes down the TTM resource manager associated with the 144 * memory region, and if it was registered with the TTM device, 145 * removes that registration. 146 */ 147 void intel_region_ttm_fini(struct intel_memory_region *mem) 148 { 149 int ret; 150 151 ret = ttm_range_man_fini(&mem->i915->bdev, 152 intel_region_to_ttm_type(mem)); 153 GEM_WARN_ON(ret); 154 mem->region_private = NULL; 155 } 156 157 /** 158 * intel_region_ttm_node_to_st - Convert an opaque TTM resource manager node 159 * to an sg_table. 160 * @mem: The memory region. 161 * @node: The resource manager node obtained from the TTM resource manager. 162 * 163 * The gem backends typically use sg-tables for operations on the underlying 164 * io_memory. So provide a way for the backends to translate the 165 * nodes they are handed from TTM to sg-tables. 166 * 167 * Return: A malloced sg_table on success, an error pointer on failure. 168 */ 169 struct sg_table *intel_region_ttm_node_to_st(struct intel_memory_region *mem, 170 struct ttm_resource *res) 171 { 172 struct ttm_range_mgr_node *range_node = 173 container_of(res, typeof(*range_node), base); 174 175 GEM_WARN_ON(!mem->is_range_manager); 176 return i915_sg_from_mm_node(&range_node->mm_nodes[0], 177 mem->region.start); 178 } 179 180 /** 181 * intel_region_ttm_node_alloc - Allocate memory resources from a region 182 * @mem: The memory region, 183 * @size: The requested size in bytes 184 * @flags: Allocation flags 185 * 186 * This functionality is provided only for callers that need to allocate 187 * memory from standalone TTM range managers, without the TTM eviction 188 * functionality. Don't use if you are not completely sure that's the 189 * case. The returned opaque node can be converted to an sg_table using 190 * intel_region_ttm_node_to_st(), and can be freed using 191 * intel_region_ttm_node_free(). 192 * 193 * Return: A valid pointer on success, an error pointer on failure. 194 */ 195 struct ttm_resource * 196 intel_region_ttm_node_alloc(struct intel_memory_region *mem, 197 resource_size_t size, 198 unsigned int flags) 199 { 200 struct ttm_resource_manager *man = mem->region_private; 201 struct ttm_place place = {}; 202 struct ttm_buffer_object mock_bo = {}; 203 struct ttm_resource *res; 204 int ret; 205 206 /* 207 * We ignore the flags for now since we're using the range 208 * manager and contigous and min page size would be fulfilled 209 * by default if size is min page size aligned. 210 */ 211 mock_bo.base.size = size; 212 213 if (mem->is_range_manager) { 214 if (size >= SZ_1G) 215 mock_bo.page_alignment = SZ_1G >> PAGE_SHIFT; 216 else if (size >= SZ_2M) 217 mock_bo.page_alignment = SZ_2M >> PAGE_SHIFT; 218 else if (size >= SZ_64K) 219 mock_bo.page_alignment = SZ_64K >> PAGE_SHIFT; 220 } 221 222 ret = man->func->alloc(man, &mock_bo, &place, &res); 223 if (ret == -ENOSPC) 224 ret = -ENXIO; 225 return ret ? ERR_PTR(ret) : res; 226 } 227