A lazy version of dma_mmap_coherent() implementation for powerpc.
The standard mmap is used as a fallback.
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
arch/powerpc/include/asm/dma-mapping.h | 22 ++++++++++++++++++++++
arch/powerpc/kernel/dma.c | 21 +++++++++++++++++++++
2 files changed, 43 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/include/asm/dma-mapping.h b/arch/powerpc/include/asm/dma-mapping.h
index b44aaab..030a4b1 100644
--- a/arch/powerpc/include/asm/dma-mapping.h
+++ b/arch/powerpc/include/asm/dma-mapping.h
@@ -105,6 +105,10 @@ struct dma_mapping_ops {
struct scatterlist *sg, int nelems,
enum dma_data_direction direction);
#endif
+ int (*mmap_coherent)(struct device *hwdev,
+ struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_handle,
+ size_t size);
};
/*
@@ -415,6 +419,24 @@ static inline void dma_sync_single_range_for_device(struct device *dev,
}
#endif
+#define ARCH_HAS_DMA_MMAP_COHERENT
+static inline int dma_mmap_coherent(struct device *dev,
+ struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_handle,
+ size_t size)
+{
+ struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+ BUG_ON(!dma_ops);
+
+ if (dma_ops->mmap_coherent)
+ return dma_ops->mmap_coherent(dev, vma, cpu_addr, dma_handle,
+ size);
+ else
+ return dma_direct_ops.mmap_coherent(dev, vma, cpu_addr,
+ dma_handle, size);
+}
+
static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
#ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c
index 20a60d6..d11db99 100644
--- a/arch/powerpc/kernel/dma.c
+++ b/arch/powerpc/kernel/dma.c
@@ -140,6 +140,26 @@ static inline void dma_direct_sync_single_range(struct device *dev,
}
#endif
+static int dma_direct_mmap_coherent(struct device *dev,
+ struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_handle,
+ size_t size)
+{
+ unsigned long pfn;
+#ifdef CONFIG_NOT_COHERENT_CACHE
+ dma_handle -= get_dma_direct_offset(dev);
+ /* assume dma_handle set via pfn_to_phys() in
+ * mm/dma-noncoherent.c
+ */
+ pfn = dma_handle >> PAGE_SHIFT;
+#else
+ pfn = page_to_pfn(virt_to_page(cpu_addr));
+#endif
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
+ size, vma->vm_page_prot);
+}
+
struct dma_mapping_ops dma_direct_ops = {
.alloc_coherent = dma_direct_alloc_coherent,
.free_coherent = dma_direct_free_coherent,
@@ -154,5 +174,6 @@ struct dma_mapping_ops dma_direct_ops = {
.sync_sg_for_cpu = dma_direct_sync_sg,
.sync_sg_for_device = dma_direct_sync_sg,
#endif
+ .mmap_coherent = dma_direct_mmap_coherent,
};
EXPORT_SYMBOL(dma_direct_ops);
--
1.6.3.2
--
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