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Diffstat (limited to 'drivers/base/dma-coherent.c')
-rw-r--r--drivers/base/dma-coherent.c434
1 files changed, 0 insertions, 434 deletions
diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
deleted file mode 100644
index 597d40893862..000000000000
--- a/drivers/base/dma-coherent.c
+++ /dev/null
@@ -1,434 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Coherent per-device memory handling.
- * Borrowed from i386
- */
-#include <linux/io.h>
-#include <linux/slab.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/dma-mapping.h>
-
-struct dma_coherent_mem {
- void *virt_base;
- dma_addr_t device_base;
- unsigned long pfn_base;
- int size;
- int flags;
- unsigned long *bitmap;
- spinlock_t spinlock;
- bool use_dev_dma_pfn_offset;
-};
-
-static struct dma_coherent_mem *dma_coherent_default_memory __ro_after_init;
-
-static inline struct dma_coherent_mem *dev_get_coherent_memory(struct device *dev)
-{
- if (dev && dev->dma_mem)
- return dev->dma_mem;
- return NULL;
-}
-
-static inline dma_addr_t dma_get_device_base(struct device *dev,
- struct dma_coherent_mem * mem)
-{
- if (mem->use_dev_dma_pfn_offset)
- return (mem->pfn_base - dev->dma_pfn_offset) << PAGE_SHIFT;
- else
- return mem->device_base;
-}
-
-static int dma_init_coherent_memory(
- phys_addr_t phys_addr, dma_addr_t device_addr, size_t size, int flags,
- struct dma_coherent_mem **mem)
-{
- struct dma_coherent_mem *dma_mem = NULL;
- void __iomem *mem_base = NULL;
- int pages = size >> PAGE_SHIFT;
- int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
- int ret;
-
- if (!size) {
- ret = -EINVAL;
- goto out;
- }
-
- mem_base = memremap(phys_addr, size, MEMREMAP_WC);
- if (!mem_base) {
- ret = -EINVAL;
- goto out;
- }
- dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
- if (!dma_mem) {
- ret = -ENOMEM;
- goto out;
- }
- dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!dma_mem->bitmap) {
- ret = -ENOMEM;
- goto out;
- }
-
- dma_mem->virt_base = mem_base;
- dma_mem->device_base = device_addr;
- dma_mem->pfn_base = PFN_DOWN(phys_addr);
- dma_mem->size = pages;
- dma_mem->flags = flags;
- spin_lock_init(&dma_mem->spinlock);
-
- *mem = dma_mem;
- return 0;
-
-out:
- kfree(dma_mem);
- if (mem_base)
- memunmap(mem_base);
- return ret;
-}
-
-static void dma_release_coherent_memory(struct dma_coherent_mem *mem)
-{
- if (!mem)
- return;
-
- memunmap(mem->virt_base);
- kfree(mem->bitmap);
- kfree(mem);
-}
-
-static int dma_assign_coherent_memory(struct device *dev,
- struct dma_coherent_mem *mem)
-{
- if (!dev)
- return -ENODEV;
-
- if (dev->dma_mem)
- return -EBUSY;
-
- dev->dma_mem = mem;
- return 0;
-}
-
-int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
- dma_addr_t device_addr, size_t size, int flags)
-{
- struct dma_coherent_mem *mem;
- int ret;
-
- ret = dma_init_coherent_memory(phys_addr, device_addr, size, flags, &mem);
- if (ret)
- return ret;
-
- ret = dma_assign_coherent_memory(dev, mem);
- if (ret)
- dma_release_coherent_memory(mem);
- return ret;
-}
-EXPORT_SYMBOL(dma_declare_coherent_memory);
-
-void dma_release_declared_memory(struct device *dev)
-{
- struct dma_coherent_mem *mem = dev->dma_mem;
-
- if (!mem)
- return;
- dma_release_coherent_memory(mem);
- dev->dma_mem = NULL;
-}
-EXPORT_SYMBOL(dma_release_declared_memory);
-
-void *dma_mark_declared_memory_occupied(struct device *dev,
- dma_addr_t device_addr, size_t size)
-{
- struct dma_coherent_mem *mem = dev->dma_mem;
- unsigned long flags;
- int pos, err;
-
- size += device_addr & ~PAGE_MASK;
-
- if (!mem)
- return ERR_PTR(-EINVAL);
-
- spin_lock_irqsave(&mem->spinlock, flags);
- pos = PFN_DOWN(device_addr - dma_get_device_base(dev, mem));
- err = bitmap_allocate_region(mem->bitmap, pos, get_order(size));
- spin_unlock_irqrestore(&mem->spinlock, flags);
-
- if (err != 0)
- return ERR_PTR(err);
- return mem->virt_base + (pos << PAGE_SHIFT);
-}
-EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
-
-static void *__dma_alloc_from_coherent(struct dma_coherent_mem *mem,
- ssize_t size, dma_addr_t *dma_handle)
-{
- int order = get_order(size);
- unsigned long flags;
- int pageno;
- void *ret;
-
- spin_lock_irqsave(&mem->spinlock, flags);
-
- if (unlikely(size > (mem->size << PAGE_SHIFT)))
- goto err;
-
- pageno = bitmap_find_free_region(mem->bitmap, mem->size, order);
- if (unlikely(pageno < 0))
- goto err;
-
- /*
- * Memory was found in the coherent area.
- */
- *dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
- ret = mem->virt_base + (pageno << PAGE_SHIFT);
- spin_unlock_irqrestore(&mem->spinlock, flags);
- memset(ret, 0, size);
- return ret;
-err:
- spin_unlock_irqrestore(&mem->spinlock, flags);
- return NULL;
-}
-
-/**
- * dma_alloc_from_dev_coherent() - allocate memory from device coherent pool
- * @dev: device from which we allocate memory
- * @size: size of requested memory area
- * @dma_handle: This will be filled with the correct dma handle
- * @ret: This pointer will be filled with the virtual address
- * to allocated area.
- *
- * This function should be only called from per-arch dma_alloc_coherent()
- * to support allocation from per-device coherent memory pools.
- *
- * Returns 0 if dma_alloc_coherent should continue with allocating from
- * generic memory areas, or !0 if dma_alloc_coherent should return @ret.
- */
-int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size,
- dma_addr_t *dma_handle, void **ret)
-{
- struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
-
- if (!mem)
- return 0;
-
- *ret = __dma_alloc_from_coherent(mem, size, dma_handle);
- if (*ret)
- return 1;
-
- /*
- * In the case where the allocation can not be satisfied from the
- * per-device area, try to fall back to generic memory if the
- * constraints allow it.
- */
- return mem->flags & DMA_MEMORY_EXCLUSIVE;
-}
-EXPORT_SYMBOL(dma_alloc_from_dev_coherent);
-
-void *dma_alloc_from_global_coherent(ssize_t size, dma_addr_t *dma_handle)
-{
- if (!dma_coherent_default_memory)
- return NULL;
-
- return __dma_alloc_from_coherent(dma_coherent_default_memory, size,
- dma_handle);
-}
-
-static int __dma_release_from_coherent(struct dma_coherent_mem *mem,
- int order, void *vaddr)
-{
- if (mem && vaddr >= mem->virt_base && vaddr <
- (mem->virt_base + (mem->size << PAGE_SHIFT))) {
- int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
- unsigned long flags;
-
- spin_lock_irqsave(&mem->spinlock, flags);
- bitmap_release_region(mem->bitmap, page, order);
- spin_unlock_irqrestore(&mem->spinlock, flags);
- return 1;
- }
- return 0;
-}
-
-/**
- * dma_release_from_dev_coherent() - free memory to device coherent memory pool
- * @dev: device from which the memory was allocated
- * @order: the order of pages allocated
- * @vaddr: virtual address of allocated pages
- *
- * This checks whether the memory was allocated from the per-device
- * coherent memory pool and if so, releases that memory.
- *
- * Returns 1 if we correctly released the memory, or 0 if the caller should
- * proceed with releasing memory from generic pools.
- */
-int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr)
-{
- struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
-
- return __dma_release_from_coherent(mem, order, vaddr);
-}
-EXPORT_SYMBOL(dma_release_from_dev_coherent);
-
-int dma_release_from_global_coherent(int order, void *vaddr)
-{
- if (!dma_coherent_default_memory)
- return 0;
-
- return __dma_release_from_coherent(dma_coherent_default_memory, order,
- vaddr);
-}
-
-static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem,
- struct vm_area_struct *vma, void *vaddr, size_t size, int *ret)
-{
- if (mem && vaddr >= mem->virt_base && vaddr + size <=
- (mem->virt_base + (mem->size << PAGE_SHIFT))) {
- unsigned long off = vma->vm_pgoff;
- int start = (vaddr - mem->virt_base) >> PAGE_SHIFT;
- int user_count = vma_pages(vma);
- int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-
- *ret = -ENXIO;
- if (off < count && user_count <= count - off) {
- unsigned long pfn = mem->pfn_base + start + off;
- *ret = remap_pfn_range(vma, vma->vm_start, pfn,
- user_count << PAGE_SHIFT,
- vma->vm_page_prot);
- }
- return 1;
- }
- return 0;
-}
-
-/**
- * dma_mmap_from_dev_coherent() - mmap memory from the device coherent pool
- * @dev: device from which the memory was allocated
- * @vma: vm_area for the userspace memory
- * @vaddr: cpu address returned by dma_alloc_from_dev_coherent
- * @size: size of the memory buffer allocated
- * @ret: result from remap_pfn_range()
- *
- * This checks whether the memory was allocated from the per-device
- * coherent memory pool and if so, maps that memory to the provided vma.
- *
- * Returns 1 if @vaddr belongs to the device coherent pool and the caller
- * should return @ret, or 0 if they should proceed with mapping memory from
- * generic areas.
- */
-int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma,
- void *vaddr, size_t size, int *ret)
-{
- struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
-
- return __dma_mmap_from_coherent(mem, vma, vaddr, size, ret);
-}
-EXPORT_SYMBOL(dma_mmap_from_dev_coherent);
-
-int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *vaddr,
- size_t size, int *ret)
-{
- if (!dma_coherent_default_memory)
- return 0;
-
- return __dma_mmap_from_coherent(dma_coherent_default_memory, vma,
- vaddr, size, ret);
-}
-
-/*
- * 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>
-
-static struct reserved_mem *dma_reserved_default_memory __initdata;
-
-static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
-{
- struct dma_coherent_mem *mem = rmem->priv;
- int ret;
-
- if (!mem) {
- ret = dma_init_coherent_memory(rmem->base, rmem->base,
- rmem->size,
- DMA_MEMORY_EXCLUSIVE, &mem);
- if (ret) {
- pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n",
- &rmem->base, (unsigned long)rmem->size / SZ_1M);
- return ret;
- }
- }
- mem->use_dev_dma_pfn_offset = true;
- rmem->priv = mem;
- dma_assign_coherent_memory(dev, mem);
- return 0;
-}
-
-static void rmem_dma_device_release(struct reserved_mem *rmem,
- struct device *dev)
-{
- if (dev)
- dev->dma_mem = NULL;
-}
-
-static const struct reserved_mem_ops rmem_dma_ops = {
- .device_init = rmem_dma_device_init,
- .device_release = rmem_dma_device_release,
-};
-
-static int __init rmem_dma_setup(struct reserved_mem *rmem)
-{
- unsigned long node = rmem->fdt_node;
-
- if (of_get_flat_dt_prop(node, "reusable", NULL))
- return -EINVAL;
-
-#ifdef CONFIG_ARM
- if (!of_get_flat_dt_prop(node, "no-map", NULL)) {
- pr_err("Reserved memory: regions without no-map are not yet supported\n");
- return -EINVAL;
- }
-
- if (of_get_flat_dt_prop(node, "linux,dma-default", NULL)) {
- WARN(dma_reserved_default_memory,
- "Reserved memory: region for default DMA coherent area is redefined\n");
- dma_reserved_default_memory = rmem;
- }
-#endif
-
- rmem->ops = &rmem_dma_ops;
- pr_info("Reserved memory: created DMA memory pool at %pa, size %ld MiB\n",
- &rmem->base, (unsigned long)rmem->size / SZ_1M);
- return 0;
-}
-
-static int __init dma_init_reserved_memory(void)
-{
- const struct reserved_mem_ops *ops;
- int ret;
-
- if (!dma_reserved_default_memory)
- return -ENOMEM;
-
- ops = dma_reserved_default_memory->ops;
-
- /*
- * We rely on rmem_dma_device_init() does not propagate error of
- * dma_assign_coherent_memory() for "NULL" device.
- */
- ret = ops->device_init(dma_reserved_default_memory, NULL);
-
- if (!ret) {
- dma_coherent_default_memory = dma_reserved_default_memory->priv;
- pr_info("DMA: default coherent area is set\n");
- }
-
- return ret;
-}
-
-core_initcall(dma_init_reserved_memory);
-
-RESERVEDMEM_OF_DECLARE(dma, "shared-dma-pool", rmem_dma_setup);
-#endif