drm/ttm/ttm_agp_backend.c

0001 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
0002 /**************************************************************************
0003  *
0004  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
0005  * All Rights Reserved.
0006  *
0007  * Permission is hereby granted, free of charge, to any person obtaining a
0008  * copy of this software and associated documentation files (the
0009  * "Software"), to deal in the Software without restriction, including
0010  * without limitation the rights to use, copy, modify, merge, publish,
0011  * distribute, sub license, and/or sell copies of the Software, and to
0012  * permit persons to whom the Software is furnished to do so, subject to
0013  * the following conditions:
0014  *
0015  * The above copyright notice and this permission notice (including the
0016  * next paragraph) shall be included in all copies or substantial portions
0017  * of the Software.
0018  *
0019  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
0020  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
0021  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
0022  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
0023  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
0024  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
0025  * USE OR OTHER DEALINGS IN THE SOFTWARE.
0026  *
0027  **************************************************************************/
0028 /*
0029  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
0030  *          Keith Packard.
0031  */
0032
0033 #define pr_fmt(fmt) "[TTM] " fmt
0034
0035 #include <drm/ttm/ttm_device.h>
0036 #include <drm/ttm/ttm_tt.h>
0037 #include <drm/ttm/ttm_resource.h>
0038 #include <linux/agp_backend.h>
0039 #include <linux/module.h>
0040 #include <linux/slab.h>
0041 #include <linux/io.h>
0042 #include <asm/agp.h>
0043
0044 struct ttm_agp_backend {
0045     struct ttm_tt ttm;
0046     struct agp_memory *mem;
0047     struct agp_bridge_data *bridge;
0048 };
0049
0050 int ttm_agp_bind(struct ttm_tt *ttm, struct ttm_resource *bo_mem)
0051 {
0052     struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
0053     struct page *dummy_read_page = ttm_glob.dummy_read_page;
0054     struct agp_memory *mem;
0055     int ret, cached = ttm->caching == ttm_cached;
0056     unsigned i;
0057
0058     if (agp_be->mem)
0059         return 0;
0060
0061     mem = agp_allocate_memory(agp_be->bridge, ttm->num_pages, AGP_USER_MEMORY);
0062     if (unlikely(mem == NULL))
0063         return -ENOMEM;
0064
0065     mem->page_count = 0;
0066     for (i = 0; i < ttm->num_pages; i++) {
0067         struct page *page = ttm->pages[i];
0068
0069         if (!page)
0070             page = dummy_read_page;
0071
0072         mem->pages[mem->page_count++] = page;
0073     }
0074     agp_be->mem = mem;
0075
0076     mem->is_flushed = 1;
0077     mem->type = (cached) ? AGP_USER_CACHED_MEMORY : AGP_USER_MEMORY;
0078
0079     ret = agp_bind_memory(mem, bo_mem->start);
0080     if (ret)
0081         pr_err("AGP Bind memory failed\n");
0082
0083     return ret;
0084 }
0085 EXPORT_SYMBOL(ttm_agp_bind);
0086
0087 void ttm_agp_unbind(struct ttm_tt *ttm)
0088 {
0089     struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
0090
0091     if (agp_be->mem) {
0092         if (agp_be->mem->is_bound) {
0093             agp_unbind_memory(agp_be->mem);
0094             return;
0095         }
0096         agp_free_memory(agp_be->mem);
0097         agp_be->mem = NULL;
0098     }
0099 }
0100 EXPORT_SYMBOL(ttm_agp_unbind);
0101
0102 bool ttm_agp_is_bound(struct ttm_tt *ttm)
0103 {
0104     struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
0105
0106     if (!ttm)
0107         return false;
0108
0109     return (agp_be->mem != NULL);
0110 }
0111 EXPORT_SYMBOL(ttm_agp_is_bound);
0112
0113 void ttm_agp_destroy(struct ttm_tt *ttm)
0114 {
0115     struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
0116
0117     if (agp_be->mem)
0118         ttm_agp_unbind(ttm);
0119     ttm_tt_fini(ttm);
0120     kfree(agp_be);
0121 }
0122 EXPORT_SYMBOL(ttm_agp_destroy);
0123
0124 struct ttm_tt *ttm_agp_tt_create(struct ttm_buffer_object *bo,
0125                  struct agp_bridge_data *bridge,
0126                  uint32_t page_flags)
0127 {
0128     struct ttm_agp_backend *agp_be;
0129
0130     agp_be = kmalloc(sizeof(*agp_be), GFP_KERNEL);
0131     if (!agp_be)
0132         return NULL;
0133
0134     agp_be->mem = NULL;
0135     agp_be->bridge = bridge;
0136
0137     if (ttm_tt_init(&agp_be->ttm, bo, page_flags, ttm_write_combined, 0)) {
0138         kfree(agp_be);
0139         return NULL;
0140     }
0141
0142     return &agp_be->ttm;
0143 }
0144 EXPORT_SYMBOL(ttm_agp_tt_create);