x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stub
[linux/fpc-iii.git] / arch / mips / mm / dma-default.c
blob5f8b955125801935f33370559476ca93f640c4df
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.
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 */
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 #include <linux/highmem.h>
20 #include <asm/cache.h>
21 #include <asm/cpu-type.h>
22 #include <asm/io.h>
24 #include <dma-coherence.h>
26 int coherentio = 0; /* User defined DMA coherency from command line. */
27 EXPORT_SYMBOL_GPL(coherentio);
28 int hw_coherentio = 0; /* Actual hardware supported DMA coherency setting. */
30 static int __init setcoherentio(char *str)
32 coherentio = 1;
33 pr_info("Hardware DMA cache coherency (command line)\n");
34 return 0;
36 early_param("coherentio", setcoherentio);
38 static int __init setnocoherentio(char *str)
40 coherentio = 0;
41 pr_info("Software DMA cache coherency (command line)\n");
42 return 0;
44 early_param("nocoherentio", setnocoherentio);
46 static inline struct page *dma_addr_to_page(struct device *dev,
47 dma_addr_t dma_addr)
49 return pfn_to_page(
50 plat_dma_addr_to_phys(dev, dma_addr) >> PAGE_SHIFT);
54 * The affected CPUs below in 'cpu_needs_post_dma_flush()' can
55 * speculatively fill random cachelines with stale data at any time,
56 * requiring an extra flush post-DMA.
58 * Warning on the terminology - Linux calls an uncached area coherent;
59 * MIPS terminology calls memory areas with hardware maintained coherency
60 * coherent.
62 static inline int cpu_needs_post_dma_flush(struct device *dev)
64 return !plat_device_is_coherent(dev) &&
65 (boot_cpu_type() == CPU_R10000 ||
66 boot_cpu_type() == CPU_R12000 ||
67 boot_cpu_type() == CPU_BMIPS5000);
70 static gfp_t massage_gfp_flags(const struct device *dev, gfp_t gfp)
72 gfp_t dma_flag;
74 /* ignore region specifiers */
75 gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
77 #ifdef CONFIG_ISA
78 if (dev == NULL)
79 dma_flag = __GFP_DMA;
80 else
81 #endif
82 #if defined(CONFIG_ZONE_DMA32) && defined(CONFIG_ZONE_DMA)
83 if (dev->coherent_dma_mask < DMA_BIT_MASK(32))
84 dma_flag = __GFP_DMA;
85 else if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
86 dma_flag = __GFP_DMA32;
87 else
88 #endif
89 #if defined(CONFIG_ZONE_DMA32) && !defined(CONFIG_ZONE_DMA)
90 if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
91 dma_flag = __GFP_DMA32;
92 else
93 #endif
94 #if defined(CONFIG_ZONE_DMA) && !defined(CONFIG_ZONE_DMA32)
95 if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
96 dma_flag = __GFP_DMA;
97 else
98 #endif
99 dma_flag = 0;
101 /* Don't invoke OOM killer */
102 gfp |= __GFP_NORETRY;
104 return gfp | dma_flag;
107 void *dma_alloc_noncoherent(struct device *dev, size_t size,
108 dma_addr_t * dma_handle, gfp_t gfp)
110 void *ret;
112 gfp = massage_gfp_flags(dev, gfp);
114 ret = (void *) __get_free_pages(gfp, get_order(size));
116 if (ret != NULL) {
117 memset(ret, 0, size);
118 *dma_handle = plat_map_dma_mem(dev, ret, size);
121 return ret;
123 EXPORT_SYMBOL(dma_alloc_noncoherent);
125 static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
126 dma_addr_t * dma_handle, gfp_t gfp, struct dma_attrs *attrs)
128 void *ret;
130 if (dma_alloc_from_coherent(dev, size, dma_handle, &ret))
131 return ret;
133 gfp = massage_gfp_flags(dev, gfp);
135 ret = (void *) __get_free_pages(gfp, get_order(size));
137 if (ret) {
138 memset(ret, 0, size);
139 *dma_handle = plat_map_dma_mem(dev, ret, size);
141 if (!plat_device_is_coherent(dev)) {
142 dma_cache_wback_inv((unsigned long) ret, size);
143 if (!hw_coherentio)
144 ret = UNCAC_ADDR(ret);
148 return ret;
152 void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
153 dma_addr_t dma_handle)
155 plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);
156 free_pages((unsigned long) vaddr, get_order(size));
158 EXPORT_SYMBOL(dma_free_noncoherent);
160 static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
161 dma_addr_t dma_handle, struct dma_attrs *attrs)
163 unsigned long addr = (unsigned long) vaddr;
164 int order = get_order(size);
166 if (dma_release_from_coherent(dev, order, vaddr))
167 return;
169 plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);
171 if (!plat_device_is_coherent(dev) && !hw_coherentio)
172 addr = CAC_ADDR(addr);
174 free_pages(addr, get_order(size));
177 static inline void __dma_sync_virtual(void *addr, size_t size,
178 enum dma_data_direction direction)
180 switch (direction) {
181 case DMA_TO_DEVICE:
182 dma_cache_wback((unsigned long)addr, size);
183 break;
185 case DMA_FROM_DEVICE:
186 dma_cache_inv((unsigned long)addr, size);
187 break;
189 case DMA_BIDIRECTIONAL:
190 dma_cache_wback_inv((unsigned long)addr, size);
191 break;
193 default:
194 BUG();
199 * A single sg entry may refer to multiple physically contiguous
200 * pages. But we still need to process highmem pages individually.
201 * If highmem is not configured then the bulk of this loop gets
202 * optimized out.
204 static inline void __dma_sync(struct page *page,
205 unsigned long offset, size_t size, enum dma_data_direction direction)
207 size_t left = size;
209 do {
210 size_t len = left;
212 if (PageHighMem(page)) {
213 void *addr;
215 if (offset + len > PAGE_SIZE) {
216 if (offset >= PAGE_SIZE) {
217 page += offset >> PAGE_SHIFT;
218 offset &= ~PAGE_MASK;
220 len = PAGE_SIZE - offset;
223 addr = kmap_atomic(page);
224 __dma_sync_virtual(addr + offset, len, direction);
225 kunmap_atomic(addr);
226 } else
227 __dma_sync_virtual(page_address(page) + offset,
228 size, direction);
229 offset = 0;
230 page++;
231 left -= len;
232 } while (left);
235 static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
236 size_t size, enum dma_data_direction direction, struct dma_attrs *attrs)
238 if (cpu_needs_post_dma_flush(dev))
239 __dma_sync(dma_addr_to_page(dev, dma_addr),
240 dma_addr & ~PAGE_MASK, size, direction);
242 plat_unmap_dma_mem(dev, dma_addr, size, direction);
245 static int mips_dma_map_sg(struct device *dev, struct scatterlist *sg,
246 int nents, enum dma_data_direction direction, struct dma_attrs *attrs)
248 int i;
250 for (i = 0; i < nents; i++, sg++) {
251 if (!plat_device_is_coherent(dev))
252 __dma_sync(sg_page(sg), sg->offset, sg->length,
253 direction);
254 #ifdef CONFIG_NEED_SG_DMA_LENGTH
255 sg->dma_length = sg->length;
256 #endif
257 sg->dma_address = plat_map_dma_mem_page(dev, sg_page(sg)) +
258 sg->offset;
261 return nents;
264 static dma_addr_t mips_dma_map_page(struct device *dev, struct page *page,
265 unsigned long offset, size_t size, enum dma_data_direction direction,
266 struct dma_attrs *attrs)
268 if (!plat_device_is_coherent(dev))
269 __dma_sync(page, offset, size, direction);
271 return plat_map_dma_mem_page(dev, page) + offset;
274 static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
275 int nhwentries, enum dma_data_direction direction,
276 struct dma_attrs *attrs)
278 int i;
280 for (i = 0; i < nhwentries; i++, sg++) {
281 if (!plat_device_is_coherent(dev) &&
282 direction != DMA_TO_DEVICE)
283 __dma_sync(sg_page(sg), sg->offset, sg->length,
284 direction);
285 plat_unmap_dma_mem(dev, sg->dma_address, sg->length, direction);
289 static void mips_dma_sync_single_for_cpu(struct device *dev,
290 dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
292 if (cpu_needs_post_dma_flush(dev))
293 __dma_sync(dma_addr_to_page(dev, dma_handle),
294 dma_handle & ~PAGE_MASK, size, direction);
297 static void mips_dma_sync_single_for_device(struct device *dev,
298 dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
300 plat_extra_sync_for_device(dev);
301 if (!plat_device_is_coherent(dev))
302 __dma_sync(dma_addr_to_page(dev, dma_handle),
303 dma_handle & ~PAGE_MASK, size, direction);
306 static void mips_dma_sync_sg_for_cpu(struct device *dev,
307 struct scatterlist *sg, int nelems, enum dma_data_direction direction)
309 int i;
311 if (cpu_needs_post_dma_flush(dev))
312 for (i = 0; i < nelems; i++, sg++)
313 __dma_sync(sg_page(sg), sg->offset, sg->length,
314 direction);
317 static void mips_dma_sync_sg_for_device(struct device *dev,
318 struct scatterlist *sg, int nelems, enum dma_data_direction direction)
320 int i;
322 if (!plat_device_is_coherent(dev))
323 for (i = 0; i < nelems; i++, sg++)
324 __dma_sync(sg_page(sg), sg->offset, sg->length,
325 direction);
328 int mips_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
330 return plat_dma_mapping_error(dev, dma_addr);
333 int mips_dma_supported(struct device *dev, u64 mask)
335 return plat_dma_supported(dev, mask);
338 void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
339 enum dma_data_direction direction)
341 BUG_ON(direction == DMA_NONE);
343 plat_extra_sync_for_device(dev);
344 if (!plat_device_is_coherent(dev))
345 __dma_sync_virtual(vaddr, size, direction);
348 EXPORT_SYMBOL(dma_cache_sync);
350 static struct dma_map_ops mips_default_dma_map_ops = {
351 .alloc = mips_dma_alloc_coherent,
352 .free = mips_dma_free_coherent,
353 .map_page = mips_dma_map_page,
354 .unmap_page = mips_dma_unmap_page,
355 .map_sg = mips_dma_map_sg,
356 .unmap_sg = mips_dma_unmap_sg,
357 .sync_single_for_cpu = mips_dma_sync_single_for_cpu,
358 .sync_single_for_device = mips_dma_sync_single_for_device,
359 .sync_sg_for_cpu = mips_dma_sync_sg_for_cpu,
360 .sync_sg_for_device = mips_dma_sync_sg_for_device,
361 .mapping_error = mips_dma_mapping_error,
362 .dma_supported = mips_dma_supported
365 struct dma_map_ops *mips_dma_map_ops = &mips_default_dma_map_ops;
366 EXPORT_SYMBOL(mips_dma_map_ops);
368 #define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
370 static int __init mips_dma_init(void)
372 dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
374 return 0;
376 fs_initcall(mips_dma_init);