drivers/base/dma-contiguous.c - kernel/msm-4.19 - Gitiles

 /*
  * Contiguous Memory Allocator for DMA mapping framework
  * Copyright (c) 2010-2011 by Samsung Electronics.
  * Written by:
  *	Marek Szyprowski <m.szyprowski@samsung.com>
  *	Michal Nazarewicz <mina86@mina86.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 of the
  * License or (at your optional) any later version of the license.
  */

 #define pr_fmt(fmt) "cma: " fmt

 #ifdef CONFIG_CMA_DEBUG
 #ifndef DEBUG
 #  define DEBUG
 #endif
 #endif

 #include <asm/page.h>
 #include <asm/dma-contiguous.h>

 #include <linux/memblock.h>
 #include <linux/err.h>
 #include <linux/sizes.h>
 #include <linux/dma-contiguous.h>
 #include <linux/cma.h>

 #ifdef CONFIG_CMA_SIZE_MBYTES
 #define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
 #else
 #define CMA_SIZE_MBYTES 0
 #endif

 struct cma *dma_contiguous_default_area;

 /*
  * Default global CMA area size can be defined in kernel's .config.
  * This is useful mainly for distro maintainers to create a kernel
  * that works correctly for most supported systems.
  * The size can be set in bytes or as a percentage of the total memory
  * in the system.
  *
  * Users, who want to set the size of global CMA area for their system
  * should use cma= kernel parameter.
  */
 static const phys_addr_t size_bytes = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M;
 static phys_addr_t size_cmdline = -1;
 static phys_addr_t base_cmdline;
 static phys_addr_t limit_cmdline;

 static int __init early_cma(char *p)
 {
 	pr_debug("%s(%s)\n", __func__, p);
 	size_cmdline = memparse(p, &p);
 	if (*p != '@')
 		return 0;
 	base_cmdline = memparse(p + 1, &p);
 	if (*p != '-') {
 		limit_cmdline = base_cmdline + size_cmdline;
 		return 0;
 	}
 	limit_cmdline = memparse(p + 1, &p);

 	return 0;
 }
 early_param("cma", early_cma);

 #ifdef CONFIG_CMA_SIZE_PERCENTAGE

 static phys_addr_t __init __maybe_unused cma_early_percent_memory(void)
 {
 	struct memblock_region *reg;
 	unsigned long total_pages = 0;

 	/*
 	 * We cannot use memblock_phys_mem_size() here, because
 	 * memblock_analyze() has not been called yet.
 	 */
 	for_each_memblock(memory, reg)
 		total_pages += memblock_region_memory_end_pfn(reg) -
 			       memblock_region_memory_base_pfn(reg);

 	return (total_pages * CONFIG_CMA_SIZE_PERCENTAGE / 100) << PAGE_SHIFT;
 }

 #else

 static inline __maybe_unused phys_addr_t cma_early_percent_memory(void)
 {
 	return 0;
 }

 #endif

 /**
  * dma_contiguous_reserve() - reserve area(s) for contiguous memory handling
  * @limit: End address of the reserved memory (optional, 0 for any).
  *
  * This function reserves memory from early allocator. It should be
  * called by arch specific code once the early allocator (memblock or bootmem)
  * has been activated and all other subsystems have already allocated/reserved
  * memory.
  */
 void __init dma_contiguous_reserve(phys_addr_t limit)
 {
 	phys_addr_t selected_size = 0;
 	phys_addr_t selected_base = 0;
 	phys_addr_t selected_limit = limit;
 	bool fixed = false;

 	pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit);

 	if (size_cmdline != -1) {
 		selected_size = size_cmdline;
 		selected_base = base_cmdline;
 		selected_limit = min_not_zero(limit_cmdline, limit);
 		if (base_cmdline + size_cmdline == limit_cmdline)
 			fixed = true;
 	} else {
 #ifdef CONFIG_CMA_SIZE_SEL_MBYTES
 		selected_size = size_bytes;
 #elif defined(CONFIG_CMA_SIZE_SEL_PERCENTAGE)
 		selected_size = cma_early_percent_memory();
 #elif defined(CONFIG_CMA_SIZE_SEL_MIN)
 		selected_size = min(size_bytes, cma_early_percent_memory());
 #elif defined(CONFIG_CMA_SIZE_SEL_MAX)
 		selected_size = max(size_bytes, cma_early_percent_memory());
 #endif
 	}

 	if (selected_size && !dma_contiguous_default_area) {
 		pr_debug("%s: reserving %ld MiB for global area\n", __func__,
 			 (unsigned long)selected_size / SZ_1M);

 		dma_contiguous_reserve_area(selected_size, selected_base,
 					    selected_limit,
 					    &dma_contiguous_default_area,
 					    fixed);
 	}
 }

 /**
  * dma_contiguous_reserve_area() - reserve custom contiguous area
  * @size: Size of the reserved area (in bytes),
  * @base: Base address of the reserved area optional, use 0 for any
  * @limit: End address of the reserved memory (optional, 0 for any).
  * @res_cma: Pointer to store the created cma region.
  * @fixed: hint about where to place the reserved area
  *
  * This function reserves memory from early allocator. It should be
  * called by arch specific code once the early allocator (memblock or bootmem)
  * has been activated and all other subsystems have already allocated/reserved
  * memory. This function allows to create custom reserved areas for specific
  * devices.
  *
  * If @fixed is true, reserve contiguous area at exactly @base.  If false,
  * reserve in range from @base to @limit.
  */
 int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
 				       phys_addr_t limit, struct cma **res_cma,
 				       bool fixed)
 {
 	int ret;

 	ret = cma_declare_contiguous(base, size, limit, 0, 0, fixed, res_cma);
 	if (ret)
 		return ret;

 	/* Architecture specific contiguous memory fixup. */
 	dma_contiguous_early_fixup(cma_get_base(*res_cma),
 				cma_get_size(*res_cma));

 	return 0;
 }

 /**
  * dma_alloc_from_contiguous() - allocate pages from contiguous area
  * @dev:   Pointer to device for which the allocation is performed.
  * @count: Requested number of pages.
  * @align: Requested alignment of pages (in PAGE_SIZE order).
  * @gfp_mask: GFP flags to use for this allocation.
  *
  * This function allocates memory buffer for specified device. It uses
  * device specific contiguous memory area if available or the default
  * global one. Requires architecture specific dev_get_cma_area() helper
  * function.
  */
 struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,
 				       unsigned int align, gfp_t gfp_mask)
 {
 	if (align > CONFIG_CMA_ALIGNMENT)
 		align = CONFIG_CMA_ALIGNMENT;

 	return cma_alloc(dev_get_cma_area(dev), count, align, gfp_mask);
 }

 /**
  * dma_release_from_contiguous() - release allocated pages
  * @dev:   Pointer to device for which the pages were allocated.
  * @pages: Allocated pages.
  * @count: Number of allocated pages.
  *
  * This function releases memory allocated by dma_alloc_from_contiguous().
  * It returns false when provided pages do not belong to contiguous area and
  * true otherwise.
  */
 bool dma_release_from_contiguous(struct device *dev, struct page *pages,
 				 int count)
 {
 	return cma_release(dev_get_cma_area(dev), pages, count);
 }

 /*
  * Support for reserved memory regions defined in device tree
  */
 #ifdef CONFIG_OF_RESERVED_MEM
 #include <linux/of.h>
 #include <linux/of_fdt.h>
 #include <linux/of_reserved_mem.h>

 #undef pr_fmt
 #define pr_fmt(fmt) fmt

 static int rmem_cma_device_init(struct reserved_mem *rmem, struct device *dev)
 {
 	dev_set_cma_area(dev, rmem->priv);
 	return 0;
 }

 static void rmem_cma_device_release(struct reserved_mem *rmem,
 				    struct device *dev)
 {
 	dev_set_cma_area(dev, NULL);
 }

 static const struct reserved_mem_ops rmem_cma_ops = {
 	.device_init	= rmem_cma_device_init,
 	.device_release = rmem_cma_device_release,
 };

 static int __init rmem_cma_setup(struct reserved_mem *rmem)
 {
 	phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
 	phys_addr_t mask = align - 1;
 	unsigned long node = rmem->fdt_node;
 	struct cma *cma;
 	int err;

 	if (!of_get_flat_dt_prop(node, "reusable", NULL) ||
 	    of_get_flat_dt_prop(node, "no-map", NULL))
 		return -EINVAL;

 	if ((rmem->base & mask) || (rmem->size & mask)) {
 		pr_err("Reserved memory: incorrect alignment of CMA region\n");
 		return -EINVAL;
 	}

 	err = cma_init_reserved_mem(rmem->base, rmem->size, 0, &cma);
 	if (err) {
 		pr_err("Reserved memory: unable to setup CMA region\n");
 		return err;
 	}
 	/* Architecture specific contiguous memory fixup. */
 	dma_contiguous_early_fixup(rmem->base, rmem->size);

 	if (of_get_flat_dt_prop(node, "linux,cma-default", NULL))
 		dma_contiguous_set_default(cma);

 	rmem->ops = &rmem_cma_ops;
 	rmem->priv = cma;

 	pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n",
 		&rmem->base, (unsigned long)rmem->size / SZ_1M);

 	return 0;
 }
 RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup);
 #endif
	/*
	* Contiguous Memory Allocator for DMA mapping framework
	* Copyright (c) 2010-2011 by Samsung Electronics.
	* Written by:
	* Marek Szyprowski <m.szyprowski@samsung.com>
	* Michal Nazarewicz <mina86@mina86.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation; either version 2 of the
	* License or (at your optional) any later version of the license.
	*/

	#define pr_fmt(fmt) "cma: " fmt

	#ifdef CONFIG_CMA_DEBUG
	#ifndef DEBUG
	# define DEBUG
	#endif
	#endif

	#include <asm/page.h>
	#include <asm/dma-contiguous.h>

	#include <linux/memblock.h>
	#include <linux/err.h>
	#include <linux/sizes.h>
	#include <linux/dma-contiguous.h>
	#include <linux/cma.h>

	#ifdef CONFIG_CMA_SIZE_MBYTES
	#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
	#else
	#define CMA_SIZE_MBYTES 0
	#endif

	struct cma *dma_contiguous_default_area;

	/*
	* Default global CMA area size can be defined in kernel's .config.
	* This is useful mainly for distro maintainers to create a kernel
	* that works correctly for most supported systems.
	* The size can be set in bytes or as a percentage of the total memory
	* in the system.
	*
	* Users, who want to set the size of global CMA area for their system
	* should use cma= kernel parameter.
	*/
	static const phys_addr_t size_bytes = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M;
	static phys_addr_t size_cmdline = -1;
	static phys_addr_t base_cmdline;
	static phys_addr_t limit_cmdline;

	static int __init early_cma(char *p)
	{
	pr_debug("%s(%s)\n", __func__, p);
	size_cmdline = memparse(p, &p);
	if (*p != '@')
	return 0;
	base_cmdline = memparse(p + 1, &p);
	if (*p != '-') {
	limit_cmdline = base_cmdline + size_cmdline;
	return 0;
	}
	limit_cmdline = memparse(p + 1, &p);

	return 0;
	}
	early_param("cma", early_cma);

	#ifdef CONFIG_CMA_SIZE_PERCENTAGE

	static phys_addr_t __init __maybe_unused cma_early_percent_memory(void)
	{
	struct memblock_region *reg;
	unsigned long total_pages = 0;

	/*
	* We cannot use memblock_phys_mem_size() here, because
	* memblock_analyze() has not been called yet.
	*/
	for_each_memblock(memory, reg)
	total_pages += memblock_region_memory_end_pfn(reg) -
	memblock_region_memory_base_pfn(reg);

	return (total_pages * CONFIG_CMA_SIZE_PERCENTAGE / 100) << PAGE_SHIFT;
	}

	#else

	static inline __maybe_unused phys_addr_t cma_early_percent_memory(void)
	{
	return 0;
	}

	#endif

	/**
	* dma_contiguous_reserve() - reserve area(s) for contiguous memory handling
	* @limit: End address of the reserved memory (optional, 0 for any).
	*
	* This function reserves memory from early allocator. It should be
	* called by arch specific code once the early allocator (memblock or bootmem)
	* has been activated and all other subsystems have already allocated/reserved
	* memory.
	*/
	void __init dma_contiguous_reserve(phys_addr_t limit)
	{
	phys_addr_t selected_size = 0;
	phys_addr_t selected_base = 0;
	phys_addr_t selected_limit = limit;
	bool fixed = false;

	pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit);

	if (size_cmdline != -1) {
	selected_size = size_cmdline;
	selected_base = base_cmdline;
	selected_limit = min_not_zero(limit_cmdline, limit);
	if (base_cmdline + size_cmdline == limit_cmdline)
	fixed = true;
	} else {
	#ifdef CONFIG_CMA_SIZE_SEL_MBYTES
	selected_size = size_bytes;
	#elif defined(CONFIG_CMA_SIZE_SEL_PERCENTAGE)
	selected_size = cma_early_percent_memory();
	#elif defined(CONFIG_CMA_SIZE_SEL_MIN)
	selected_size = min(size_bytes, cma_early_percent_memory());
	#elif defined(CONFIG_CMA_SIZE_SEL_MAX)
	selected_size = max(size_bytes, cma_early_percent_memory());
	#endif
	}

	if (selected_size && !dma_contiguous_default_area) {
	pr_debug("%s: reserving %ld MiB for global area\n", __func__,
	(unsigned long)selected_size / SZ_1M);

	dma_contiguous_reserve_area(selected_size, selected_base,
	selected_limit,
	&dma_contiguous_default_area,
	fixed);
	}
	}

	/**
	* dma_contiguous_reserve_area() - reserve custom contiguous area
	* @size: Size of the reserved area (in bytes),
	* @base: Base address of the reserved area optional, use 0 for any
	* @limit: End address of the reserved memory (optional, 0 for any).
	* @res_cma: Pointer to store the created cma region.
	* @fixed: hint about where to place the reserved area
	*
	* This function reserves memory from early allocator. It should be
	* called by arch specific code once the early allocator (memblock or bootmem)
	* has been activated and all other subsystems have already allocated/reserved
	* memory. This function allows to create custom reserved areas for specific
	* devices.
	*
	* If @fixed is true, reserve contiguous area at exactly @base. If false,
	* reserve in range from @base to @limit.
	*/
	int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
	phys_addr_t limit, struct cma **res_cma,
	bool fixed)
	{
	int ret;

	ret = cma_declare_contiguous(base, size, limit, 0, 0, fixed, res_cma);
	if (ret)
	return ret;

	/* Architecture specific contiguous memory fixup. */
	dma_contiguous_early_fixup(cma_get_base(*res_cma),
	cma_get_size(*res_cma));

	return 0;
	}

	/**
	* dma_alloc_from_contiguous() - allocate pages from contiguous area
	* @dev: Pointer to device for which the allocation is performed.
	* @count: Requested number of pages.
	* @align: Requested alignment of pages (in PAGE_SIZE order).
	* @gfp_mask: GFP flags to use for this allocation.
	*
	* This function allocates memory buffer for specified device. It uses
	* device specific contiguous memory area if available or the default
	* global one. Requires architecture specific dev_get_cma_area() helper
	* function.
	*/
	struct page dma_alloc_from_contiguous(struct device dev, size_t count,
	unsigned int align, gfp_t gfp_mask)
	{
	if (align > CONFIG_CMA_ALIGNMENT)
	align = CONFIG_CMA_ALIGNMENT;

	return cma_alloc(dev_get_cma_area(dev), count, align, gfp_mask);
	}

	/**
	* dma_release_from_contiguous() - release allocated pages
	* @dev: Pointer to device for which the pages were allocated.
	* @pages: Allocated pages.
	* @count: Number of allocated pages.
	*
	* This function releases memory allocated by dma_alloc_from_contiguous().
	* It returns false when provided pages do not belong to contiguous area and
	* true otherwise.
	*/
	bool dma_release_from_contiguous(struct device dev, struct page pages,
	int count)
	{
	return cma_release(dev_get_cma_area(dev), pages, count);
	}

	/*
	* Support for reserved memory regions defined in device tree
	*/
	#ifdef CONFIG_OF_RESERVED_MEM
	#include <linux/of.h>
	#include <linux/of_fdt.h>
	#include <linux/of_reserved_mem.h>

	#undef pr_fmt
	#define pr_fmt(fmt) fmt

	static int rmem_cma_device_init(struct reserved_mem rmem, struct device dev)
	{
	dev_set_cma_area(dev, rmem->priv);
	return 0;
	}

	static void rmem_cma_device_release(struct reserved_mem *rmem,
	struct device *dev)
	{
	dev_set_cma_area(dev, NULL);
	}

	static const struct reserved_mem_ops rmem_cma_ops = {
	.device_init = rmem_cma_device_init,
	.device_release = rmem_cma_device_release,
	};

	static int __init rmem_cma_setup(struct reserved_mem *rmem)
	{
	phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
	phys_addr_t mask = align - 1;
	unsigned long node = rmem->fdt_node;
	struct cma *cma;
	int err;

	if (!of_get_flat_dt_prop(node, "reusable", NULL) \|\|
	of_get_flat_dt_prop(node, "no-map", NULL))
	return -EINVAL;

	if ((rmem->base & mask) \|\| (rmem->size & mask)) {
	pr_err("Reserved memory: incorrect alignment of CMA region\n");
	return -EINVAL;
	}

	err = cma_init_reserved_mem(rmem->base, rmem->size, 0, &cma);
	if (err) {
	pr_err("Reserved memory: unable to setup CMA region\n");
	return err;
	}
	/* Architecture specific contiguous memory fixup. */
	dma_contiguous_early_fixup(rmem->base, rmem->size);

	if (of_get_flat_dt_prop(node, "linux,cma-default", NULL))
	dma_contiguous_set_default(cma);

	rmem->ops = &rmem_cma_ops;
	rmem->priv = cma;

	pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n",
	&rmem->base, (unsigned long)rmem->size / SZ_1M);

	return 0;
	}
	RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup);
	#endif