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authorOlof Johansson <olof@lixom.net>2012-09-16 19:28:42 -0700
committerOlof Johansson <olof@lixom.net>2012-09-16 19:28:42 -0700
commite640ca0fcb8b616c92a660605fddd1cc9e4bde1d (patch)
tree1d942cf747504b3db772bca447be7eea4228c722 /arch/arm/mm
parent5ec8d8c96e20f4997881c8f259607cc8e47825e2 (diff)
parentcf3a6ec2c0a499ef019d25d4dbc79df66e7d3f0c (diff)
downloadblackbird-obmc-linux-e640ca0fcb8b616c92a660605fddd1cc9e4bde1d.tar.gz
blackbird-obmc-linux-e640ca0fcb8b616c92a660605fddd1cc9e4bde1d.zip
Merge tag 'cleanup-omap-tags-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/cleanup
From Tony Lindgren: Remove the ancient omap specific atags that are no longer needed. At some point we were planning to pass the bootloader information with custom atags that did not work out too well. There's no need for these any longer as the kernel has been booting fine without them for quite some time. And Now we have device tree support that can be used instead. * tag 'cleanup-omap-tags-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: ARM: OMAP: remove plat/board.h file ARM: OMAP: move debug_card_init() function ARM: OMAP1: move lcd pdata out of arch/arm/* ARM: OMAP1: move omap1_bl pdata out of arch/arm/* ARM: OMAP: remove the omap custom tags ARM: OMAP1: remove the crystal type tag parsing ARM: OMAP: remove the sti console workaround ARM: OMAP: omap3evm: cleanup revision bits ARM: OMAP: cleanup struct omap_board_config_kernel + sync to 3.6-rc5
Diffstat (limited to 'arch/arm/mm')
-rw-r--r--arch/arm/mm/dma-mapping.c114
1 files changed, 104 insertions, 10 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 4e7d1182e8a3..051204fc4617 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -267,17 +267,19 @@ static void __dma_free_remap(void *cpu_addr, size_t size)
vunmap(cpu_addr);
}
+#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K
+
struct dma_pool {
size_t size;
spinlock_t lock;
unsigned long *bitmap;
unsigned long nr_pages;
void *vaddr;
- struct page *page;
+ struct page **pages;
};
static struct dma_pool atomic_pool = {
- .size = SZ_256K,
+ .size = DEFAULT_DMA_COHERENT_POOL_SIZE,
};
static int __init early_coherent_pool(char *p)
@@ -287,6 +289,21 @@ static int __init early_coherent_pool(char *p)
}
early_param("coherent_pool", early_coherent_pool);
+void __init init_dma_coherent_pool_size(unsigned long size)
+{
+ /*
+ * Catch any attempt to set the pool size too late.
+ */
+ BUG_ON(atomic_pool.vaddr);
+
+ /*
+ * Set architecture specific coherent pool size only if
+ * it has not been changed by kernel command line parameter.
+ */
+ if (atomic_pool.size == DEFAULT_DMA_COHERENT_POOL_SIZE)
+ atomic_pool.size = size;
+}
+
/*
* Initialise the coherent pool for atomic allocations.
*/
@@ -297,6 +314,7 @@ static int __init atomic_pool_init(void)
unsigned long nr_pages = pool->size >> PAGE_SHIFT;
unsigned long *bitmap;
struct page *page;
+ struct page **pages;
void *ptr;
int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long);
@@ -304,21 +322,31 @@ static int __init atomic_pool_init(void)
if (!bitmap)
goto no_bitmap;
+ pages = kzalloc(nr_pages * sizeof(struct page *), GFP_KERNEL);
+ if (!pages)
+ goto no_pages;
+
if (IS_ENABLED(CONFIG_CMA))
ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page);
else
ptr = __alloc_remap_buffer(NULL, pool->size, GFP_KERNEL, prot,
&page, NULL);
if (ptr) {
+ int i;
+
+ for (i = 0; i < nr_pages; i++)
+ pages[i] = page + i;
+
spin_lock_init(&pool->lock);
pool->vaddr = ptr;
- pool->page = page;
+ pool->pages = pages;
pool->bitmap = bitmap;
pool->nr_pages = nr_pages;
pr_info("DMA: preallocated %u KiB pool for atomic coherent allocations\n",
(unsigned)pool->size / 1024);
return 0;
}
+no_pages:
kfree(bitmap);
no_bitmap:
pr_err("DMA: failed to allocate %u KiB pool for atomic coherent allocation\n",
@@ -443,27 +471,45 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page)
if (pageno < pool->nr_pages) {
bitmap_set(pool->bitmap, pageno, count);
ptr = pool->vaddr + PAGE_SIZE * pageno;
- *ret_page = pool->page + pageno;
+ *ret_page = pool->pages[pageno];
+ } else {
+ pr_err_once("ERROR: %u KiB atomic DMA coherent pool is too small!\n"
+ "Please increase it with coherent_pool= kernel parameter!\n",
+ (unsigned)pool->size / 1024);
}
spin_unlock_irqrestore(&pool->lock, flags);
return ptr;
}
+static bool __in_atomic_pool(void *start, size_t size)
+{
+ struct dma_pool *pool = &atomic_pool;
+ void *end = start + size;
+ void *pool_start = pool->vaddr;
+ void *pool_end = pool->vaddr + pool->size;
+
+ if (start < pool_start || start > pool_end)
+ return false;
+
+ if (end <= pool_end)
+ return true;
+
+ WARN(1, "Wrong coherent size(%p-%p) from atomic pool(%p-%p)\n",
+ start, end - 1, pool_start, pool_end - 1);
+
+ return false;
+}
+
static int __free_from_pool(void *start, size_t size)
{
struct dma_pool *pool = &atomic_pool;
unsigned long pageno, count;
unsigned long flags;
- if (start < pool->vaddr || start > pool->vaddr + pool->size)
+ if (!__in_atomic_pool(start, size))
return 0;
- if (start + size > pool->vaddr + pool->size) {
- WARN(1, "freeing wrong coherent size from pool\n");
- return 0;
- }
-
pageno = (start - pool->vaddr) >> PAGE_SHIFT;
count = size >> PAGE_SHIFT;
@@ -1090,10 +1136,22 @@ static int __iommu_remove_mapping(struct device *dev, dma_addr_t iova, size_t si
return 0;
}
+static struct page **__atomic_get_pages(void *addr)
+{
+ struct dma_pool *pool = &atomic_pool;
+ struct page **pages = pool->pages;
+ int offs = (addr - pool->vaddr) >> PAGE_SHIFT;
+
+ return pages + offs;
+}
+
static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
{
struct vm_struct *area;
+ if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
+ return __atomic_get_pages(cpu_addr);
+
if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
return cpu_addr;
@@ -1103,6 +1161,34 @@ static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
return NULL;
}
+static void *__iommu_alloc_atomic(struct device *dev, size_t size,
+ dma_addr_t *handle)
+{
+ struct page *page;
+ void *addr;
+
+ addr = __alloc_from_pool(size, &page);
+ if (!addr)
+ return NULL;
+
+ *handle = __iommu_create_mapping(dev, &page, size);
+ if (*handle == DMA_ERROR_CODE)
+ goto err_mapping;
+
+ return addr;
+
+err_mapping:
+ __free_from_pool(addr, size);
+ return NULL;
+}
+
+static void __iommu_free_atomic(struct device *dev, struct page **pages,
+ dma_addr_t handle, size_t size)
+{
+ __iommu_remove_mapping(dev, handle, size);
+ __free_from_pool(page_address(pages[0]), size);
+}
+
static void *arm_iommu_alloc_attrs(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
{
@@ -1113,6 +1199,9 @@ static void *arm_iommu_alloc_attrs(struct device *dev, size_t size,
*handle = DMA_ERROR_CODE;
size = PAGE_ALIGN(size);
+ if (gfp & GFP_ATOMIC)
+ return __iommu_alloc_atomic(dev, size, handle);
+
pages = __iommu_alloc_buffer(dev, size, gfp);
if (!pages)
return NULL;
@@ -1179,6 +1268,11 @@ void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
return;
}
+ if (__in_atomic_pool(cpu_addr, size)) {
+ __iommu_free_atomic(dev, pages, handle, size);
+ return;
+ }
+
if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs)) {
unmap_kernel_range((unsigned long)cpu_addr, size);
vunmap(cpu_addr);
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