arch/mips/mm/dma-default.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2000  Ani Joshi <ajoshi@unixbox.com>
   7  * Copyright (C) 2000, 2001, 06  Ralf Baechle <ralf@linux-mips.org>
   8  * swiped from i386, and cloned for MIPS by Geert, polished by Ralf.
   9  */
  10
  11 #include <linux/types.h>
  12 #include <linux/dma-mapping.h>
  13 #include <linux/mm.h>
  14 #include <linux/module.h>
  15 #include <linux/scatterlist.h>
  16 #include <linux/string.h>
  17 #include <linux/gfp.h>
  18
  19 #include <asm/cache.h>
  20 #include <asm/io.h>
  21
  22 #include <dma-coherence.h>
  23
  24 static inline unsigned long dma_addr_to_virt(struct device *dev,
  25         dma_addr_t dma_addr)
  26 {
  27         unsigned long addr = plat_dma_addr_to_phys(dev, dma_addr);
  28
  29         return (unsigned long)phys_to_virt(addr);
  30 }
  31
  32 /*
  33  * Warning on the terminology - Linux calls an uncached area coherent;
  34  * MIPS terminology calls memory areas with hardware maintained coherency
  35  * coherent.
  36  */
  37
  38 static inline int cpu_is_noncoherent_r10000(struct device *dev)
  39 {
  40         return !plat_device_is_coherent(dev) &&
  41                (current_cpu_type() == CPU_R10000 ||
  42                current_cpu_type() == CPU_R12000);
  43 }
  44
  45 static gfp_t massage_gfp_flags(const struct device *dev, gfp_t gfp)
  46 {
  47         gfp_t dma_flag;
  48
  49         /* ignore region specifiers */
  50         gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
  51
  52 #ifdef CONFIG_ISA
  53         if (dev == NULL)
  54                 dma_flag = __GFP_DMA;
  55         else
  56 #endif
  57 #if defined(CONFIG_ZONE_DMA32) && defined(CONFIG_ZONE_DMA)
  58              if (dev->coherent_dma_mask < DMA_BIT_MASK(32))
  59                         dma_flag = __GFP_DMA;
  60         else if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
  61                         dma_flag = __GFP_DMA32;
  62         else
  63 #endif
  64 #if defined(CONFIG_ZONE_DMA32) && !defined(CONFIG_ZONE_DMA)
  65              if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
  66                 dma_flag = __GFP_DMA32;
  67         else
  68 #endif
  69 #if defined(CONFIG_ZONE_DMA) && !defined(CONFIG_ZONE_DMA32)
  70              if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
  71                 dma_flag = __GFP_DMA;
  72         else
  73 #endif
  74                 dma_flag = 0;
  75
  76         /* Don't invoke OOM killer */
  77         gfp |= __GFP_NORETRY;
  78
  79         return gfp | dma_flag;
  80 }
  81
  82 void *dma_alloc_noncoherent(struct device *dev, size_t size,
  83         dma_addr_t * dma_handle, gfp_t gfp)
  84 {
  85         void *ret;
  86
  87         gfp = massage_gfp_flags(dev, gfp);
  88
  89         ret = (void *) __get_free_pages(gfp, get_order(size));
  90
  91         if (ret != NULL) {
  92                 memset(ret, 0, size);
  93                 *dma_handle = plat_map_dma_mem(dev, ret, size);
  94         }
  95
  96         return ret;
  97 }
  98 EXPORT_SYMBOL(dma_alloc_noncoherent);
  99
 100 static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
 101         dma_addr_t * dma_handle, gfp_t gfp)
 102 {
 103         void *ret;
 104
 105         if (dma_alloc_from_coherent(dev, size, dma_handle, &ret))
 106                 return ret;
 107
 108         gfp = massage_gfp_flags(dev, gfp);
 109
 110         ret = (void *) __get_free_pages(gfp, get_order(size));
 111
 112         if (ret) {
 113                 memset(ret, 0, size);
 114                 *dma_handle = plat_map_dma_mem(dev, ret, size);
 115
 116                 if (!plat_device_is_coherent(dev)) {
 117                         dma_cache_wback_inv((unsigned long) ret, size);
 118                         ret = UNCAC_ADDR(ret);
 119                 }
 120         }
 121
 122         return ret;
 123 }
 124
 125
 126 void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
 127         dma_addr_t dma_handle)
 128 {
 129         plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);
 130         free_pages((unsigned long) vaddr, get_order(size));
 131 }
 132 EXPORT_SYMBOL(dma_free_noncoherent);
 133
 134 static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
 135         dma_addr_t dma_handle)
 136 {
 137         unsigned long addr = (unsigned long) vaddr;
 138         int order = get_order(size);
 139
 140         if (dma_release_from_coherent(dev, order, vaddr))
 141                 return;
 142
 143         plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);
 144
 145         if (!plat_device_is_coherent(dev))
 146                 addr = CAC_ADDR(addr);
 147
 148         free_pages(addr, get_order(size));
 149 }
 150
 151 static inline void __dma_sync(unsigned long addr, size_t size,
 152         enum dma_data_direction direction)
 153 {
 154         switch (direction) {
 155         case DMA_TO_DEVICE:
 156                 dma_cache_wback(addr, size);
 157                 break;
 158
 159         case DMA_FROM_DEVICE:
 160                 dma_cache_inv(addr, size);
 161                 break;
 162
 163         case DMA_BIDIRECTIONAL:
 164                 dma_cache_wback_inv(addr, size);
 165                 break;
 166
 167         default:
 168                 BUG();
 169         }
 170 }
 171
 172 static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
 173         size_t size, enum dma_data_direction direction, struct dma_attrs *attrs)
 174 {
 175         if (cpu_is_noncoherent_r10000(dev))
 176                 __dma_sync(dma_addr_to_virt(dev, dma_addr), size,
 177                            direction);
 178
 179         plat_unmap_dma_mem(dev, dma_addr, size, direction);
 180 }
 181
 182 static int mips_dma_map_sg(struct device *dev, struct scatterlist *sg,
 183         int nents, enum dma_data_direction direction, struct dma_attrs *attrs)
 184 {
 185         int i;
 186
 187         for (i = 0; i < nents; i++, sg++) {
 188                 unsigned long addr;
 189
 190                 addr = (unsigned long) sg_virt(sg);
 191                 if (!plat_device_is_coherent(dev) && addr)
 192                         __dma_sync(addr, sg->length, direction);
 193                 sg->dma_address = plat_map_dma_mem(dev,
 194                                                    (void *)addr, sg->length);
 195         }
 196
 197         return nents;
 198 }
 199
 200 static dma_addr_t mips_dma_map_page(struct device *dev, struct page *page,
 201         unsigned long offset, size_t size, enum dma_data_direction direction,
 202         struct dma_attrs *attrs)
 203 {
 204         unsigned long addr;
 205
 206         addr = (unsigned long) page_address(page) + offset;
 207
 208         if (!plat_device_is_coherent(dev))
 209                 __dma_sync(addr, size, direction);
 210
 211         return plat_map_dma_mem(dev, (void *)addr, size);
 212 }
 213
 214 static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 215         int nhwentries, enum dma_data_direction direction,
 216         struct dma_attrs *attrs)
 217 {
 218         unsigned long addr;
 219         int i;
 220
 221         for (i = 0; i < nhwentries; i++, sg++) {
 222                 if (!plat_device_is_coherent(dev) &&
 223                     direction != DMA_TO_DEVICE) {
 224                         addr = (unsigned long) sg_virt(sg);
 225                         if (addr)
 226                                 __dma_sync(addr, sg->length, direction);
 227                 }
 228                 plat_unmap_dma_mem(dev, sg->dma_address, sg->length, direction);
 229         }
 230 }
 231
 232 static void mips_dma_sync_single_for_cpu(struct device *dev,
 233         dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
 234 {
 235         if (cpu_is_noncoherent_r10000(dev)) {
 236                 unsigned long addr;
 237
 238                 addr = dma_addr_to_virt(dev, dma_handle);
 239                 __dma_sync(addr, size, direction);
 240         }
 241 }
 242
 243 static void mips_dma_sync_single_for_device(struct device *dev,
 244         dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
 245 {
 246         plat_extra_sync_for_device(dev);
 247         if (!plat_device_is_coherent(dev)) {
 248                 unsigned long addr;
 249
 250                 addr = dma_addr_to_virt(dev, dma_handle);
 251                 __dma_sync(addr, size, direction);
 252         }
 253 }
 254
 255 static void mips_dma_sync_sg_for_cpu(struct device *dev,
 256         struct scatterlist *sg, int nelems, enum dma_data_direction direction)
 257 {
 258         int i;
 259
 260         /* Make sure that gcc doesn't leave the empty loop body.  */
 261         for (i = 0; i < nelems; i++, sg++) {
 262                 if (cpu_is_noncoherent_r10000(dev))
 263                         __dma_sync((unsigned long)page_address(sg_page(sg)),
 264                                    sg->length, direction);
 265         }
 266 }
 267
 268 static void mips_dma_sync_sg_for_device(struct device *dev,
 269         struct scatterlist *sg, int nelems, enum dma_data_direction direction)
 270 {
 271         int i;
 272
 273         /* Make sure that gcc doesn't leave the empty loop body.  */
 274         for (i = 0; i < nelems; i++, sg++) {
 275                 if (!plat_device_is_coherent(dev))
 276                         __dma_sync((unsigned long)page_address(sg_page(sg)),
 277                                    sg->length, direction);
 278         }
 279 }
 280
 281 int mips_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 282 {
 283         return plat_dma_mapping_error(dev, dma_addr);
 284 }
 285
 286 int mips_dma_supported(struct device *dev, u64 mask)
 287 {
 288         return plat_dma_supported(dev, mask);
 289 }
 290
 291 void mips_dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 292                          enum dma_data_direction direction)
 293 {
 294         BUG_ON(direction == DMA_NONE);
 295
 296         plat_extra_sync_for_device(dev);
 297         if (!plat_device_is_coherent(dev))
 298                 __dma_sync((unsigned long)vaddr, size, direction);
 299 }
 300
 301 static struct dma_map_ops mips_default_dma_map_ops = {
 302         .alloc_coherent = mips_dma_alloc_coherent,
 303         .free_coherent = mips_dma_free_coherent,
 304         .map_page = mips_dma_map_page,
 305         .unmap_page = mips_dma_unmap_page,
 306         .map_sg = mips_dma_map_sg,
 307         .unmap_sg = mips_dma_unmap_sg,
 308         .sync_single_for_cpu = mips_dma_sync_single_for_cpu,
 309         .sync_single_for_device = mips_dma_sync_single_for_device,
 310         .sync_sg_for_cpu = mips_dma_sync_sg_for_cpu,
 311         .sync_sg_for_device = mips_dma_sync_sg_for_device,
 312         .mapping_error = mips_dma_mapping_error,
 313         .dma_supported = mips_dma_supported
 314 };
 315
 316 struct dma_map_ops *mips_dma_map_ops = &mips_default_dma_map_ops;
 317 EXPORT_SYMBOL(mips_dma_map_ops);
 318
 319 #define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
 320
 321 static int __init mips_dma_init(void)
 322 {
 323         dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
 324
 325         return 0;
 326 }
 327 fs_initcall(mips_dma_init);