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1// SPDX-License-Identifier: GPL-2.0-or-later2/* exynos_drm_gem.c3 *4 * Copyright (c) 2011 Samsung Electronics Co., Ltd.5 * Author: Inki Dae <inki.dae@samsung.com>6 */7 8 9#include <linux/dma-buf.h>10#include <linux/pfn_t.h>11#include <linux/shmem_fs.h>12#include <linux/module.h>13 14#include <drm/drm_prime.h>15#include <drm/drm_vma_manager.h>16#include <drm/exynos_drm.h>17 18#include "exynos_drm_drv.h"19#include "exynos_drm_gem.h"20 21MODULE_IMPORT_NS(DMA_BUF);22 23static int exynos_drm_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma);24 25static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem, bool kvmap)26{27 struct drm_device *dev = exynos_gem->base.dev;28 unsigned long attr = 0;29 30 if (exynos_gem->dma_addr) {31 DRM_DEV_DEBUG_KMS(to_dma_dev(dev), "already allocated.\n");32 return 0;33 }34 35 /*36 * if EXYNOS_BO_CONTIG, fully physically contiguous memory37 * region will be allocated else physically contiguous38 * as possible.39 */40 if (!(exynos_gem->flags & EXYNOS_BO_NONCONTIG))41 attr |= DMA_ATTR_FORCE_CONTIGUOUS;42 43 /*44 * if EXYNOS_BO_WC or EXYNOS_BO_NONCACHABLE, writecombine mapping45 * else cachable mapping.46 */47 if (exynos_gem->flags & EXYNOS_BO_WC ||48 !(exynos_gem->flags & EXYNOS_BO_CACHABLE))49 attr |= DMA_ATTR_WRITE_COMBINE;50 51 /* FBDev emulation requires kernel mapping */52 if (!kvmap)53 attr |= DMA_ATTR_NO_KERNEL_MAPPING;54 55 exynos_gem->dma_attrs = attr;56 exynos_gem->cookie = dma_alloc_attrs(to_dma_dev(dev), exynos_gem->size,57 &exynos_gem->dma_addr, GFP_KERNEL,58 exynos_gem->dma_attrs);59 if (!exynos_gem->cookie) {60 DRM_DEV_ERROR(to_dma_dev(dev), "failed to allocate buffer.\n");61 return -ENOMEM;62 }63 64 if (kvmap)65 exynos_gem->kvaddr = exynos_gem->cookie;66 67 DRM_DEV_DEBUG_KMS(to_dma_dev(dev), "dma_addr(0x%lx), size(0x%lx)\n",68 (unsigned long)exynos_gem->dma_addr, exynos_gem->size);69 return 0;70}71 72static void exynos_drm_free_buf(struct exynos_drm_gem *exynos_gem)73{74 struct drm_device *dev = exynos_gem->base.dev;75 76 if (!exynos_gem->dma_addr) {77 DRM_DEV_DEBUG_KMS(dev->dev, "dma_addr is invalid.\n");78 return;79 }80 81 DRM_DEV_DEBUG_KMS(dev->dev, "dma_addr(0x%lx), size(0x%lx)\n",82 (unsigned long)exynos_gem->dma_addr, exynos_gem->size);83 84 dma_free_attrs(to_dma_dev(dev), exynos_gem->size, exynos_gem->cookie,85 (dma_addr_t)exynos_gem->dma_addr,86 exynos_gem->dma_attrs);87}88 89static int exynos_drm_gem_handle_create(struct drm_gem_object *obj,90 struct drm_file *file_priv,91 unsigned int *handle)92{93 int ret;94 95 /*96 * allocate a id of idr table where the obj is registered97 * and handle has the id what user can see.98 */99 ret = drm_gem_handle_create(file_priv, obj, handle);100 if (ret)101 return ret;102 103 DRM_DEV_DEBUG_KMS(to_dma_dev(obj->dev), "gem handle = 0x%x\n", *handle);104 105 /* drop reference from allocate - handle holds it now. */106 drm_gem_object_put(obj);107 108 return 0;109}110 111void exynos_drm_gem_destroy(struct exynos_drm_gem *exynos_gem)112{113 struct drm_gem_object *obj = &exynos_gem->base;114 115 DRM_DEV_DEBUG_KMS(to_dma_dev(obj->dev), "handle count = %d\n",116 obj->handle_count);117 118 /*119 * do not release memory region from exporter.120 *121 * the region will be released by exporter122 * once dmabuf's refcount becomes 0.123 */124 if (obj->import_attach)125 drm_prime_gem_destroy(obj, exynos_gem->sgt);126 else127 exynos_drm_free_buf(exynos_gem);128 129 /* release file pointer to gem object. */130 drm_gem_object_release(obj);131 132 kfree(exynos_gem);133}134 135static const struct vm_operations_struct exynos_drm_gem_vm_ops = {136 .open = drm_gem_vm_open,137 .close = drm_gem_vm_close,138};139 140static const struct drm_gem_object_funcs exynos_drm_gem_object_funcs = {141 .free = exynos_drm_gem_free_object,142 .get_sg_table = exynos_drm_gem_prime_get_sg_table,143 .mmap = exynos_drm_gem_mmap,144 .vm_ops = &exynos_drm_gem_vm_ops,145};146 147static struct exynos_drm_gem *exynos_drm_gem_init(struct drm_device *dev,148 unsigned long size)149{150 struct exynos_drm_gem *exynos_gem;151 struct drm_gem_object *obj;152 int ret;153 154 exynos_gem = kzalloc(sizeof(*exynos_gem), GFP_KERNEL);155 if (!exynos_gem)156 return ERR_PTR(-ENOMEM);157 158 exynos_gem->size = size;159 obj = &exynos_gem->base;160 161 obj->funcs = &exynos_drm_gem_object_funcs;162 163 ret = drm_gem_object_init(dev, obj, size);164 if (ret < 0) {165 DRM_DEV_ERROR(dev->dev, "failed to initialize gem object\n");166 kfree(exynos_gem);167 return ERR_PTR(ret);168 }169 170 ret = drm_gem_create_mmap_offset(obj);171 if (ret < 0) {172 drm_gem_object_release(obj);173 kfree(exynos_gem);174 return ERR_PTR(ret);175 }176 177 DRM_DEV_DEBUG_KMS(dev->dev, "created file object = %pK\n", obj->filp);178 179 return exynos_gem;180}181 182struct exynos_drm_gem *exynos_drm_gem_create(struct drm_device *dev,183 unsigned int flags,184 unsigned long size,185 bool kvmap)186{187 struct exynos_drm_gem *exynos_gem;188 int ret;189 190 if (flags & ~(EXYNOS_BO_MASK)) {191 DRM_DEV_ERROR(dev->dev,192 "invalid GEM buffer flags: %u\n", flags);193 return ERR_PTR(-EINVAL);194 }195 196 if (!size) {197 DRM_DEV_ERROR(dev->dev, "invalid GEM buffer size: %lu\n", size);198 return ERR_PTR(-EINVAL);199 }200 201 size = roundup(size, PAGE_SIZE);202 203 exynos_gem = exynos_drm_gem_init(dev, size);204 if (IS_ERR(exynos_gem))205 return exynos_gem;206 207 if (!is_drm_iommu_supported(dev) && (flags & EXYNOS_BO_NONCONTIG)) {208 /*209 * when no IOMMU is available, all allocated buffers are210 * contiguous anyway, so drop EXYNOS_BO_NONCONTIG flag211 */212 flags &= ~EXYNOS_BO_NONCONTIG;213 DRM_WARN("Non-contiguous allocation is not supported without IOMMU, falling back to contiguous buffer\n");214 }215 216 /* set memory type and cache attribute from user side. */217 exynos_gem->flags = flags;218 219 ret = exynos_drm_alloc_buf(exynos_gem, kvmap);220 if (ret < 0) {221 drm_gem_object_release(&exynos_gem->base);222 kfree(exynos_gem);223 return ERR_PTR(ret);224 }225 226 return exynos_gem;227}228 229int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data,230 struct drm_file *file_priv)231{232 struct drm_exynos_gem_create *args = data;233 struct exynos_drm_gem *exynos_gem;234 int ret;235 236 exynos_gem = exynos_drm_gem_create(dev, args->flags, args->size, false);237 if (IS_ERR(exynos_gem))238 return PTR_ERR(exynos_gem);239 240 ret = exynos_drm_gem_handle_create(&exynos_gem->base, file_priv,241 &args->handle);242 if (ret) {243 exynos_drm_gem_destroy(exynos_gem);244 return ret;245 }246 247 return 0;248}249 250int exynos_drm_gem_map_ioctl(struct drm_device *dev, void *data,251 struct drm_file *file_priv)252{253 struct drm_exynos_gem_map *args = data;254 255 return drm_gem_dumb_map_offset(file_priv, dev, args->handle,256 &args->offset);257}258 259struct exynos_drm_gem *exynos_drm_gem_get(struct drm_file *filp,260 unsigned int gem_handle)261{262 struct drm_gem_object *obj;263 264 obj = drm_gem_object_lookup(filp, gem_handle);265 if (!obj)266 return NULL;267 return to_exynos_gem(obj);268}269 270static int exynos_drm_gem_mmap_buffer(struct exynos_drm_gem *exynos_gem,271 struct vm_area_struct *vma)272{273 struct drm_device *drm_dev = exynos_gem->base.dev;274 unsigned long vm_size;275 int ret;276 277 vm_flags_clear(vma, VM_PFNMAP);278 vma->vm_pgoff = 0;279 280 vm_size = vma->vm_end - vma->vm_start;281 282 /* check if user-requested size is valid. */283 if (vm_size > exynos_gem->size)284 return -EINVAL;285 286 ret = dma_mmap_attrs(to_dma_dev(drm_dev), vma, exynos_gem->cookie,287 exynos_gem->dma_addr, exynos_gem->size,288 exynos_gem->dma_attrs);289 if (ret < 0) {290 DRM_ERROR("failed to mmap.\n");291 return ret;292 }293 294 return 0;295}296 297int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data,298 struct drm_file *file_priv)299{300 struct exynos_drm_gem *exynos_gem;301 struct drm_exynos_gem_info *args = data;302 struct drm_gem_object *obj;303 304 obj = drm_gem_object_lookup(file_priv, args->handle);305 if (!obj) {306 DRM_DEV_ERROR(dev->dev, "failed to lookup gem object.\n");307 return -EINVAL;308 }309 310 exynos_gem = to_exynos_gem(obj);311 312 args->flags = exynos_gem->flags;313 args->size = exynos_gem->size;314 315 drm_gem_object_put(obj);316 317 return 0;318}319 320void exynos_drm_gem_free_object(struct drm_gem_object *obj)321{322 exynos_drm_gem_destroy(to_exynos_gem(obj));323}324 325int exynos_drm_gem_dumb_create(struct drm_file *file_priv,326 struct drm_device *dev,327 struct drm_mode_create_dumb *args)328{329 struct exynos_drm_gem *exynos_gem;330 unsigned int flags;331 int ret;332 333 /*334 * allocate memory to be used for framebuffer.335 * - this callback would be called by user application336 * with DRM_IOCTL_MODE_CREATE_DUMB command.337 */338 339 args->pitch = args->width * ((args->bpp + 7) / 8);340 args->size = args->pitch * args->height;341 342 if (is_drm_iommu_supported(dev))343 flags = EXYNOS_BO_NONCONTIG | EXYNOS_BO_WC;344 else345 flags = EXYNOS_BO_CONTIG | EXYNOS_BO_WC;346 347 exynos_gem = exynos_drm_gem_create(dev, flags, args->size, false);348 if (IS_ERR(exynos_gem)) {349 dev_warn(dev->dev, "FB allocation failed.\n");350 return PTR_ERR(exynos_gem);351 }352 353 ret = exynos_drm_gem_handle_create(&exynos_gem->base, file_priv,354 &args->handle);355 if (ret) {356 exynos_drm_gem_destroy(exynos_gem);357 return ret;358 }359 360 return 0;361}362 363static int exynos_drm_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)364{365 struct exynos_drm_gem *exynos_gem = to_exynos_gem(obj);366 int ret;367 368 if (obj->import_attach)369 return dma_buf_mmap(obj->dma_buf, vma, 0);370 371 vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP);372 373 DRM_DEV_DEBUG_KMS(to_dma_dev(obj->dev), "flags = 0x%x\n",374 exynos_gem->flags);375 376 /* non-cachable as default. */377 if (exynos_gem->flags & EXYNOS_BO_CACHABLE)378 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);379 else if (exynos_gem->flags & EXYNOS_BO_WC)380 vma->vm_page_prot =381 pgprot_writecombine(vm_get_page_prot(vma->vm_flags));382 else383 vma->vm_page_prot =384 pgprot_noncached(vm_get_page_prot(vma->vm_flags));385 386 ret = exynos_drm_gem_mmap_buffer(exynos_gem, vma);387 if (ret)388 goto err_close_vm;389 390 return ret;391 392err_close_vm:393 drm_gem_vm_close(vma);394 395 return ret;396}397 398/* low-level interface prime helpers */399struct drm_gem_object *exynos_drm_gem_prime_import(struct drm_device *dev,400 struct dma_buf *dma_buf)401{402 return drm_gem_prime_import_dev(dev, dma_buf, to_dma_dev(dev));403}404 405struct sg_table *exynos_drm_gem_prime_get_sg_table(struct drm_gem_object *obj)406{407 struct exynos_drm_gem *exynos_gem = to_exynos_gem(obj);408 struct drm_device *drm_dev = obj->dev;409 struct sg_table *sgt;410 int ret;411 412 sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);413 if (!sgt)414 return ERR_PTR(-ENOMEM);415 416 ret = dma_get_sgtable_attrs(to_dma_dev(drm_dev), sgt, exynos_gem->cookie,417 exynos_gem->dma_addr, exynos_gem->size,418 exynos_gem->dma_attrs);419 if (ret) {420 DRM_ERROR("failed to get sgtable, %d\n", ret);421 kfree(sgt);422 return ERR_PTR(ret);423 }424 425 return sgt;426}427 428struct drm_gem_object *429exynos_drm_gem_prime_import_sg_table(struct drm_device *dev,430 struct dma_buf_attachment *attach,431 struct sg_table *sgt)432{433 struct exynos_drm_gem *exynos_gem;434 435 /* check if the entries in the sg_table are contiguous */436 if (drm_prime_get_contiguous_size(sgt) < attach->dmabuf->size) {437 DRM_ERROR("buffer chunks must be mapped contiguously");438 return ERR_PTR(-EINVAL);439 }440 441 exynos_gem = exynos_drm_gem_init(dev, attach->dmabuf->size);442 if (IS_ERR(exynos_gem))443 return ERR_CAST(exynos_gem);444 445 /*446 * Buffer has been mapped as contiguous into DMA address space,447 * but if there is IOMMU, it can be either CONTIG or NONCONTIG.448 * We assume a simplified logic below:449 */450 if (is_drm_iommu_supported(dev))451 exynos_gem->flags |= EXYNOS_BO_NONCONTIG;452 else453 exynos_gem->flags |= EXYNOS_BO_CONTIG;454 455 exynos_gem->dma_addr = sg_dma_address(sgt->sgl);456 exynos_gem->sgt = sgt;457 return &exynos_gem->base;458}459