1 /* 2 * \file drm_memory.c 3 * Memory management wrappers for DRM 4 * 5 * \author Rickard E. (Rik) Faith <faith@valinux.com> 6 * \author Gareth Hughes <gareth@valinux.com> 7 */ 8 9 /* 10 * Created: Thu Feb 4 14:00:34 1999 by faith@valinux.com 11 * 12 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. 13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. 14 * All Rights Reserved. 15 * 16 * Permission is hereby granted, free of charge, to any person obtaining a 17 * copy of this software and associated documentation files (the "Software"), 18 * to deal in the Software without restriction, including without limitation 19 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 20 * and/or sell copies of the Software, and to permit persons to whom the 21 * Software is furnished to do so, subject to the following conditions: 22 * 23 * The above copyright notice and this permission notice (including the next 24 * paragraph) shall be included in all copies or substantial portions of the 25 * Software. 26 * 27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 28 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 29 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 30 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 31 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 32 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 33 * OTHER DEALINGS IN THE SOFTWARE. 34 */ 35 36 #include <linux/export.h> 37 #include <linux/highmem.h> 38 #include <linux/pci.h> 39 #include <linux/vmalloc.h> 40 #ifdef __linux__ 41 #include <xen/xen.h> 42 #endif 43 44 #include <drm/drm_agpsupport.h> 45 #include <drm/drm_cache.h> 46 #include <drm/drm_device.h> 47 48 #include "drm_legacy.h" 49 50 #if IS_ENABLED(CONFIG_AGP) && defined(__linux__) 51 52 #ifdef HAVE_PAGE_AGP 53 # include <asm/agp.h> 54 #else 55 # ifdef __powerpc__ 56 # define PAGE_AGP pgprot_noncached_wc(PAGE_KERNEL) 57 # else 58 # define PAGE_AGP PAGE_KERNEL 59 # endif 60 #endif 61 62 static void *agp_remap(unsigned long offset, unsigned long size, 63 struct drm_device *dev) 64 { 65 unsigned long i, num_pages = 66 PAGE_ALIGN(size) / PAGE_SIZE; 67 struct drm_agp_mem *agpmem; 68 struct vm_page **page_map; 69 struct vm_page **phys_page_map; 70 void *addr; 71 72 size = PAGE_ALIGN(size); 73 74 #ifdef __alpha__ 75 offset -= dev->hose->mem_space->start; 76 #endif 77 78 list_for_each_entry(agpmem, &dev->agp->memory, head) 79 if (agpmem->bound <= offset 80 && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >= 81 (offset + size)) 82 break; 83 if (&agpmem->head == &dev->agp->memory) 84 return NULL; 85 86 /* 87 * OK, we're mapping AGP space on a chipset/platform on which memory accesses by 88 * the CPU do not get remapped by the GART. We fix this by using the kernel's 89 * page-table instead (that's probably faster anyhow...). 90 */ 91 /* note: use vmalloc() because num_pages could be large... */ 92 page_map = vmalloc(array_size(num_pages, sizeof(struct vm_page *))); 93 if (!page_map) 94 return NULL; 95 96 phys_page_map = (agpmem->memory->pages + (offset - agpmem->bound) / PAGE_SIZE); 97 for (i = 0; i < num_pages; ++i) 98 page_map[i] = phys_page_map[i]; 99 addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP); 100 vfree(page_map); 101 102 return addr; 103 } 104 105 /** Wrapper around agp_free_memory() */ 106 void drm_free_agp(struct agp_memory *handle, int pages) 107 { 108 agp_free_memory(handle); 109 } 110 111 /** Wrapper around agp_bind_memory() */ 112 int drm_bind_agp(struct agp_memory *handle, unsigned int start) 113 { 114 return agp_bind_memory(handle, start); 115 } 116 117 /** Wrapper around agp_unbind_memory() */ 118 int drm_unbind_agp(struct agp_memory *handle) 119 { 120 return agp_unbind_memory(handle); 121 } 122 123 #else /* CONFIG_AGP */ 124 static inline void *agp_remap(unsigned long offset, unsigned long size, 125 struct drm_device *dev) 126 { 127 return NULL; 128 } 129 130 #endif /* CONFIG_AGP */ 131 132 #ifdef __linux__ 133 134 void drm_legacy_ioremap(struct drm_local_map *map, struct drm_device *dev) 135 { 136 if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP) 137 map->handle = agp_remap(map->offset, map->size, dev); 138 else 139 map->handle = ioremap(map->offset, map->size); 140 } 141 EXPORT_SYMBOL(drm_legacy_ioremap); 142 143 void drm_legacy_ioremap_wc(struct drm_local_map *map, struct drm_device *dev) 144 { 145 if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP) 146 map->handle = agp_remap(map->offset, map->size, dev); 147 else 148 map->handle = ioremap_wc(map->offset, map->size); 149 } 150 EXPORT_SYMBOL(drm_legacy_ioremap_wc); 151 152 void drm_legacy_ioremapfree(struct drm_local_map *map, struct drm_device *dev) 153 { 154 if (!map->handle || !map->size) 155 return; 156 157 if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP) 158 vunmap(map->handle); 159 else 160 iounmap(map->handle); 161 } 162 EXPORT_SYMBOL(drm_legacy_ioremapfree); 163 164 #endif /* __linux__ */ 165 166 bool drm_need_swiotlb(int dma_bits) 167 { 168 return false; 169 #ifdef notyet 170 struct resource *tmp; 171 resource_size_t max_iomem = 0; 172 173 /* 174 * Xen paravirtual hosts require swiotlb regardless of requested dma 175 * transfer size. 176 * 177 * NOTE: Really, what it requires is use of the dma_alloc_coherent 178 * allocator used in ttm_dma_populate() instead of 179 * ttm_populate_and_map_pages(), which bounce buffers so much in 180 * Xen it leads to swiotlb buffer exhaustion. 181 */ 182 if (xen_pv_domain()) 183 return true; 184 185 /* 186 * Enforce dma_alloc_coherent when memory encryption is active as well 187 * for the same reasons as for Xen paravirtual hosts. 188 */ 189 if (mem_encrypt_active()) 190 return true; 191 192 for (tmp = iomem_resource.child; tmp; tmp = tmp->sibling) { 193 max_iomem = max(max_iomem, tmp->end); 194 } 195 196 return max_iomem > ((u64)1 << dma_bits); 197 #endif 198 } 199 EXPORT_SYMBOL(drm_need_swiotlb); 200