diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
index 7d6e84a..8f88c91 100644
--- a/drivers/base/dma-coherent.c
+++ b/drivers/base/dma-coherent.c
@@ -14,11 +14,14 @@ struct dma_coherent_mem {
int size;
int flags;
unsigned long *bitmap;
+ spinlock_t spinlock;
};
-int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
- dma_addr_t device_addr, size_t size, int flags)
+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);@@ -27,27 +30,26 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
goto out;
if (!size)
goto out;
- if (dev->dma_mem)
- goto out;
-
- /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
mem_base = ioremap(phys_addr, size);
if (!mem_base)
goto out;
- dev->dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
- if (!dev->dma_mem)
+ dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
+ if (!dma_mem)
goto out;
- dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!dev->dma_mem->bitmap)
+ dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
+ if (!dma_mem->bitmap)
goto free1_out;
- dev->dma_mem->virt_base = mem_base;
- dev->dma_mem->device_base = device_addr;
- dev->dma_mem->pfn_base = PFN_DOWN(phys_addr);
- dev->dma_mem->size = pages;
- dev->dma_mem->flags = flags;
+ 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;
if (flags & DMA_MEMORY_MAP)
return DMA_MEMORY_MAP;
@@ -55,12 +57,51 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
return DMA_MEMORY_IO;
free1_out:
- kfree(dev->dma_mem);
+ kfree(dma_mem);
out:
if (mem_base)
iounmap(mem_base);
return 0;
}
+
+static void dma_release_coherent_memory(struct dma_coherent_mem *mem)
+{
+ if (!mem)
+ return;
+ iounmap(mem->virt_base);
+ kfree(mem->bitmap);
+ kfree(mem);
+}
+
+static int dma_assign_coherent_memory(struct device *dev,
+ struct dma_coherent_mem *mem)
+{
+ if (dev->dma_mem)
+ return -EBUSY;
+
+ dev->dma_mem = mem;
+ /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
+
+ 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 == 0)
+ return 0;
+
+ if (dma_assign_coherent_memory(dev, mem) == 0)
+ return ret;
+
+ dma_release_coherent_memory(mem);
+ return 0;
+}
EXPORT_SYMBOL(dma_declare_coherent_memory);
void dma_release_declared_memory(struct device *dev)@@ -69,10 +110,8 @@ void dma_release_declared_memory(struct device *dev)
if (!mem)
return;
+ dma_release_coherent_memory(mem);
dev->dma_mem = NULL;
- iounmap(mem->virt_base);
- kfree(mem->bitmap);
- kfree(mem);
}
EXPORT_SYMBOL(dma_release_declared_memory);
@@ -80,6 +119,7 @@ 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;@@ -87,8 +127,11 @@ void *dma_mark_declared_memory_occupied(struct device *dev,
if (!mem)
return ERR_PTR(-EINVAL);
+ spin_lock_irqsave(&mem->spinlock, flags);
pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
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);
@@ -115,6 +158,7 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
{
struct dma_coherent_mem *mem;
int order = get_order(size);
+ unsigned long flags;
int pageno;
if (!dev)@@ -124,6 +168,7 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
return 0;
*ret = NULL;
+ spin_lock_irqsave(&mem->spinlock, flags);
if (unlikely(size > (mem->size << PAGE_SHIFT)))
goto err;
@@ -138,10 +183,12 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
*dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
*ret = mem->virt_base + (pageno << PAGE_SHIFT);
memset(*ret, 0, size);
+ spin_unlock_irqrestore(&mem->spinlock, flags);
return 1;
err:
+ spin_unlock_irqrestore(&mem->spinlock, flags);
/*
* In the case where the allocation can not be satisfied from the
* per-device area, try to fall back to generic memory if the
@@ -171,8 +218,11 @@ int dma_release_from_coherent(struct device *dev, 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;@@ -218,3 +268,60 @@ int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
return 0;
}
EXPORT_SYMBOL(dma_mmap_from_coherent);
+
+/*
+ * 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 int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
+{
+ struct dma_coherent_mem *mem = rmem->priv;
+ if (!mem &&
+ dma_init_coherent_memory(rmem->base, rmem->base, rmem->size,
+ DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE,
+ &mem) != DMA_MEMORY_MAP) {
+ pr_info("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n",
+ &rmem->base, (unsigned long)rmem->size / SZ_1M);
+ return -ENODEV;
+ }
+ rmem->priv = mem;
+ dma_assign_coherent_memory(dev, mem);
+ return 0;
+}
+
+static void rmem_dma_device_release(struct reserved_mem *rmem,
+ struct device *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_info("Reserved memory: regions without no-map are not yet supported\n");
+ return -EINVAL;
+ }
+#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;
+}
+RESERVEDMEM_OF_DECLARE(dma, "shared-dma-pool", rmem_dma_setup);
+#endif--
1.9.2