drm_memory.c revision 1.29
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 62static 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() */ 106void drm_free_agp(struct agp_memory *handle, int pages) 107{ 108 agp_free_memory(handle); 109} 110 111/** Wrapper around agp_bind_memory() */ 112int 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() */ 118int drm_unbind_agp(struct agp_memory *handle) 119{ 120 return agp_unbind_memory(handle); 121} 122 123#else /* CONFIG_AGP */ 124static 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 134void 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} 141EXPORT_SYMBOL(drm_legacy_ioremap); 142 143void 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} 150EXPORT_SYMBOL(drm_legacy_ioremap_wc); 151 152void 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} 162EXPORT_SYMBOL(drm_legacy_ioremapfree); 163 164#endif /* __linux__ */ 165 166bool drm_need_swiotlb(int dma_bits) 167{ 168 STUB(); 169 return false; 170#ifdef notyet 171 struct resource *tmp; 172 resource_size_t max_iomem = 0; 173 174 /* 175 * Xen paravirtual hosts require swiotlb regardless of requested dma 176 * transfer size. 177 * 178 * NOTE: Really, what it requires is use of the dma_alloc_coherent 179 * allocator used in ttm_dma_populate() instead of 180 * ttm_populate_and_map_pages(), which bounce buffers so much in 181 * Xen it leads to swiotlb buffer exhaustion. 182 */ 183 if (xen_pv_domain()) 184 return true; 185 186 /* 187 * Enforce dma_alloc_coherent when memory encryption is active as well 188 * for the same reasons as for Xen paravirtual hosts. 189 */ 190 if (mem_encrypt_active()) 191 return true; 192 193 for (tmp = iomem_resource.child; tmp; tmp = tmp->sibling) { 194 max_iomem = max(max_iomem, tmp->end); 195 } 196 197 return max_iomem > ((u64)1 << dma_bits); 198#endif 199} 200EXPORT_SYMBOL(drm_need_swiotlb); 201