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10#define pr_fmt(fmt) "cma: " fmt
11
12#ifdef CONFIG_CMA_DEBUG
13#ifndef DEBUG
14# define DEBUG
15#endif
16#endif
17
18#include <asm/page.h>
19#include <asm/dma-contiguous.h>
20
21#include <linux/memblock.h>
22#include <linux/err.h>
23#include <linux/sizes.h>
24#include <linux/dma-contiguous.h>
25#include <linux/cma.h>
26
27#ifdef CONFIG_CMA_SIZE_MBYTES
28#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
29#else
30#define CMA_SIZE_MBYTES 0
31#endif
32
33struct cma *dma_contiguous_default_area;
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45static const phys_addr_t size_bytes __initconst =
46 (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M;
47static phys_addr_t size_cmdline __initdata = -1;
48static phys_addr_t base_cmdline __initdata;
49static phys_addr_t limit_cmdline __initdata;
50
51static int __init early_cma(char *p)
52{
53 if (!p) {
54 pr_err("Config string not provided\n");
55 return -EINVAL;
56 }
57
58 size_cmdline = memparse(p, &p);
59 if (*p != '@')
60 return 0;
61 base_cmdline = memparse(p + 1, &p);
62 if (*p != '-') {
63 limit_cmdline = base_cmdline + size_cmdline;
64 return 0;
65 }
66 limit_cmdline = memparse(p + 1, &p);
67
68 return 0;
69}
70early_param("cma", early_cma);
71
72#ifdef CONFIG_CMA_SIZE_PERCENTAGE
73
74static phys_addr_t __init __maybe_unused cma_early_percent_memory(void)
75{
76 struct memblock_region *reg;
77 unsigned long total_pages = 0;
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83 for_each_memblock(memory, reg)
84 total_pages += memblock_region_memory_end_pfn(reg) -
85 memblock_region_memory_base_pfn(reg);
86
87 return (total_pages * CONFIG_CMA_SIZE_PERCENTAGE / 100) << PAGE_SHIFT;
88}
89
90#else
91
92static inline __maybe_unused phys_addr_t cma_early_percent_memory(void)
93{
94 return 0;
95}
96
97#endif
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108void __init dma_contiguous_reserve(phys_addr_t limit)
109{
110 phys_addr_t selected_size = 0;
111 phys_addr_t selected_base = 0;
112 phys_addr_t selected_limit = limit;
113 bool fixed = false;
114
115 pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit);
116
117 if (size_cmdline != -1) {
118 selected_size = size_cmdline;
119 selected_base = base_cmdline;
120 selected_limit = min_not_zero(limit_cmdline, limit);
121 if (base_cmdline + size_cmdline == limit_cmdline)
122 fixed = true;
123 } else {
124#ifdef CONFIG_CMA_SIZE_SEL_MBYTES
125 selected_size = size_bytes;
126#elif defined(CONFIG_CMA_SIZE_SEL_PERCENTAGE)
127 selected_size = cma_early_percent_memory();
128#elif defined(CONFIG_CMA_SIZE_SEL_MIN)
129 selected_size = min(size_bytes, cma_early_percent_memory());
130#elif defined(CONFIG_CMA_SIZE_SEL_MAX)
131 selected_size = max(size_bytes, cma_early_percent_memory());
132#endif
133 }
134
135 if (selected_size && !dma_contiguous_default_area) {
136 pr_debug("%s: reserving %ld MiB for global area\n", __func__,
137 (unsigned long)selected_size / SZ_1M);
138
139 dma_contiguous_reserve_area(selected_size, selected_base,
140 selected_limit,
141 &dma_contiguous_default_area,
142 fixed);
143 }
144}
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163int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
164 phys_addr_t limit, struct cma **res_cma,
165 bool fixed)
166{
167 int ret;
168
169 ret = cma_declare_contiguous(base, size, limit, 0, 0, fixed,
170 "reserved", res_cma);
171 if (ret)
172 return ret;
173
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175 dma_contiguous_early_fixup(cma_get_base(*res_cma),
176 cma_get_size(*res_cma));
177
178 return 0;
179}
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193struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,
194 unsigned int align, bool no_warn)
195{
196 if (align > CONFIG_CMA_ALIGNMENT)
197 align = CONFIG_CMA_ALIGNMENT;
198
199 return cma_alloc(dev_get_cma_area(dev), count, align, no_warn);
200}
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212bool dma_release_from_contiguous(struct device *dev, struct page *pages,
213 int count)
214{
215 return cma_release(dev_get_cma_area(dev), pages, count);
216}
217
218static struct page *cma_alloc_aligned(struct cma *cma, size_t size, gfp_t gfp)
219{
220 unsigned int align = min(get_order(size), CONFIG_CMA_ALIGNMENT);
221
222 return cma_alloc(cma, size >> PAGE_SHIFT, align, gfp & __GFP_NOWARN);
223}
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239struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp)
240{
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242 if (!gfpflags_allow_blocking(gfp))
243 return NULL;
244 if (dev->cma_area)
245 return cma_alloc_aligned(dev->cma_area, size, gfp);
246 if (size <= PAGE_SIZE || !dma_contiguous_default_area)
247 return NULL;
248 return cma_alloc_aligned(dma_contiguous_default_area, size, gfp);
249}
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262void dma_free_contiguous(struct device *dev, struct page *page, size_t size)
263{
264 if (!cma_release(dev_get_cma_area(dev), page,
265 PAGE_ALIGN(size) >> PAGE_SHIFT))
266 __free_pages(page, get_order(size));
267}
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272#ifdef CONFIG_OF_RESERVED_MEM
273#include <linux/of.h>
274#include <linux/of_fdt.h>
275#include <linux/of_reserved_mem.h>
276
277#undef pr_fmt
278#define pr_fmt(fmt) fmt
279
280static int rmem_cma_device_init(struct reserved_mem *rmem, struct device *dev)
281{
282 dev_set_cma_area(dev, rmem->priv);
283 return 0;
284}
285
286static void rmem_cma_device_release(struct reserved_mem *rmem,
287 struct device *dev)
288{
289 dev_set_cma_area(dev, NULL);
290}
291
292static const struct reserved_mem_ops rmem_cma_ops = {
293 .device_init = rmem_cma_device_init,
294 .device_release = rmem_cma_device_release,
295};
296
297static int __init rmem_cma_setup(struct reserved_mem *rmem)
298{
299 phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
300 phys_addr_t mask = align - 1;
301 unsigned long node = rmem->fdt_node;
302 bool default_cma = of_get_flat_dt_prop(node, "linux,cma-default", NULL);
303 struct cma *cma;
304 int err;
305
306 if (size_cmdline != -1 && default_cma) {
307 pr_info("Reserved memory: bypass %s node, using cmdline CMA params instead\n",
308 rmem->name);
309 return -EBUSY;
310 }
311
312 if (!of_get_flat_dt_prop(node, "reusable", NULL) ||
313 of_get_flat_dt_prop(node, "no-map", NULL))
314 return -EINVAL;
315
316 if ((rmem->base & mask) || (rmem->size & mask)) {
317 pr_err("Reserved memory: incorrect alignment of CMA region\n");
318 return -EINVAL;
319 }
320
321 err = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name, &cma);
322 if (err) {
323 pr_err("Reserved memory: unable to setup CMA region\n");
324 return err;
325 }
326
327 dma_contiguous_early_fixup(rmem->base, rmem->size);
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329 if (default_cma)
330 dma_contiguous_set_default(cma);
331
332 rmem->ops = &rmem_cma_ops;
333 rmem->priv = cma;
334
335 pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n",
336 &rmem->base, (unsigned long)rmem->size / SZ_1M);
337
338 return 0;
339}
340RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup);
341#endif
342