1 // SPDX-License-Identifier: GPL-2.0+
4  * Copyright (c) 2010-2011 by Samsung Electronics.
17  *   Various devices on embedded systems have no scatter-getter and/or
30  *   inaccessible to page system even if device drivers don't use it.
40 #include <asm/page.h>
45 #include <linux/dma-map-ops.h>
58  * Default global CMA area size can be defined in kernel's .config.
61  * The size can be set in bytes or as a percentage of the total memory
64  * Users, who want to set the size of global CMA area for their system
69 static phys_addr_t  size_cmdline __initdata = -1;
77 		return -EINVAL;  in early_cma()
84 	if (*p != '-') {  in early_cma()
204  * dma_contiguous_reserve() - reserve area(s) for contiguous memory handling
223 	if (size_cmdline != -1) {  in dma_contiguous_reserve()
253 dma_contiguous_early_fixup(phys_addr_t base, unsigned long size)  in dma_contiguous_early_fixup()  argument
258  * dma_contiguous_reserve_area() - reserve custom contiguous area
259  * @size: Size of the reserved area (in bytes),
274 int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,  in dma_contiguous_reserve_area()  argument
280 	ret = cma_declare_contiguous(base, size, limit, 0, 0, fixed,  in dma_contiguous_reserve_area()
293  * dma_alloc_from_contiguous() - allocate pages from contiguous area
304 struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,  in dma_alloc_from_contiguous()
314  * dma_release_from_contiguous() - release allocated pages
323 bool dma_release_from_contiguous(struct device *dev, struct page *pages,  in dma_release_from_contiguous()
329 static struct page *cma_alloc_aligned(struct cma *cma, size_t size, gfp_t gfp)  in cma_alloc_aligned()  argument
331 	unsigned int align = min(get_order(size), CONFIG_CMA_ALIGNMENT);  in cma_alloc_aligned()
333 	return cma_alloc(cma, size >> PAGE_SHIFT, align, gfp & __GFP_NOWARN);  in cma_alloc_aligned()
337  * dma_alloc_contiguous() - allocate contiguous pages
339  * @size:  Requested allocation size.
343  * tries to use per-numa cma, if the allocation fails, it will fallback to
346  * Note that it bypass one-page size of allocations from the per-numa and
347  * global area as the addresses within one page are always contiguous, so
351 struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp)  in dma_alloc_contiguous()  argument
360 	if (dev->cma_area)  in dma_alloc_contiguous()
361 		return cma_alloc_aligned(dev->cma_area, size, gfp);  in dma_alloc_contiguous()
362 	if (size <= PAGE_SIZE)  in dma_alloc_contiguous()
368 		struct page *page;  in dma_alloc_contiguous()  local
371 			page = cma_alloc_aligned(cma, size, gfp);  in dma_alloc_contiguous()
372 			if (page)  in dma_alloc_contiguous()
373 				return page;  in dma_alloc_contiguous()
378 			page = cma_alloc_aligned(cma, size, gfp);  in dma_alloc_contiguous()
379 			if (page)  in dma_alloc_contiguous()
380 				return page;  in dma_alloc_contiguous()
387 	return cma_alloc_aligned(dma_contiguous_default_area, size, gfp);  in dma_alloc_contiguous()
391  * dma_free_contiguous() - release allocated pages
393  * @page:  Pointer to the allocated pages.
394  * @size:  Size of allocated pages.
399  * upon a false-return.
401 void dma_free_contiguous(struct device *dev, struct page *page, size_t size)  in dma_free_contiguous()  argument
403 	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;  in dma_free_contiguous()
405 	/* if dev has its own cma, free page from there */  in dma_free_contiguous()
406 	if (dev->cma_area) {  in dma_free_contiguous()
407 		if (cma_release(dev->cma_area, page, count))  in dma_free_contiguous()
411 		 * otherwise, page is from either per-numa cma or default cma  in dma_free_contiguous()
414 		if (cma_release(dma_contiguous_pernuma_area[page_to_nid(page)],  in dma_free_contiguous()
415 					page, count))  in dma_free_contiguous()
417 		if (cma_release(dma_contiguous_numa_area[page_to_nid(page)],  in dma_free_contiguous()
418 					page, count))  in dma_free_contiguous()
421 		if (cma_release(dma_contiguous_default_area, page, count))  in dma_free_contiguous()
426 	__free_pages(page, get_order(size));  in dma_free_contiguous()
442 	dev->cma_area = rmem->priv;  in rmem_cma_device_init()
449 	dev->cma_area = NULL;  in rmem_cma_device_release()
459 	unsigned long node = rmem->fdt_node;  in rmem_cma_setup()
460 	bool default_cma = of_get_flat_dt_prop(node, "linux,cma-default", NULL);  in rmem_cma_setup()
464 	if (size_cmdline != -1 && default_cma) {  in rmem_cma_setup()
466 			rmem->name);  in rmem_cma_setup()
467 		return -EBUSY;  in rmem_cma_setup()
471 	    of_get_flat_dt_prop(node, "no-map", NULL))  in rmem_cma_setup()
472 		return -EINVAL;  in rmem_cma_setup()
474 	if (!IS_ALIGNED(rmem->base | rmem->size, CMA_MIN_ALIGNMENT_BYTES)) {  in rmem_cma_setup()
476 		return -EINVAL;  in rmem_cma_setup()
479 	err = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name, &cma);  in rmem_cma_setup()
485 	dma_contiguous_early_fixup(rmem->base, rmem->size);  in rmem_cma_setup()
490 	rmem->ops = &rmem_cma_ops;  in rmem_cma_setup()
491 	rmem->priv = cma;  in rmem_cma_setup()
493 	pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n",  in rmem_cma_setup()
494 		&rmem->base, (unsigned long)rmem->size / SZ_1M);  in rmem_cma_setup()
498 RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup);