[PATCH 2/4] ARM: add coherent iommu dma ops
Rob Herring
robherring2 at gmail.com
Mon Aug 13 23:49:05 EDT 2012
From: Rob Herring <rob.herring at calxeda.com>
Remove arch_is_coherent() from iommu dma ops and implement separate
coherent ops functions.
Signed-off-by: Rob Herring <rob.herring at calxeda.com>
Cc: Russell King <linux at arm.linux.org.uk>
Cc: Marek Szyprowski <m.szyprowski at samsung.com>
---
arch/arm/mm/dma-mapping.c | 183 +++++++++++++++++++++++++++++++++++----------
1 file changed, 143 insertions(+), 40 deletions(-)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index c14e37e..29c3b3a 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1254,7 +1254,8 @@ static int arm_iommu_get_sgtable(struct device *dev, struct sg_table *sgt,
*/
static int __map_sg_chunk(struct device *dev, struct scatterlist *sg,
size_t size, dma_addr_t *handle,
- enum dma_data_direction dir, struct dma_attrs *attrs)
+ enum dma_data_direction dir, struct dma_attrs *attrs,
+ bool is_coherent)
{
struct dma_iommu_mapping *mapping = dev->archdata.mapping;
dma_addr_t iova, iova_base;
@@ -1273,8 +1274,8 @@ static int __map_sg_chunk(struct device *dev, struct scatterlist *sg,
phys_addr_t phys = page_to_phys(sg_page(s));
unsigned int len = PAGE_ALIGN(s->offset + s->length);
- if (!arch_is_coherent() &&
- !dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+ if (!is_coherent &&
+ !dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
__dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
ret = iommu_map(mapping->domain, iova, phys, len, 0);
@@ -1292,20 +1293,9 @@ fail:
return ret;
}
-/**
- * arm_iommu_map_sg - map a set of SG buffers for streaming mode DMA
- * @dev: valid struct device pointer
- * @sg: list of buffers
- * @nents: number of buffers to map
- * @dir: DMA transfer direction
- *
- * Map a set of buffers described by scatterlist in streaming mode for DMA.
- * The scatter gather list elements are merged together (if possible) and
- * tagged with the appropriate dma address and length. They are obtained via
- * sg_dma_{address,length}.
- */
-int arm_iommu_map_sg(struct device *dev, struct scatterlist *sg, int nents,
- enum dma_data_direction dir, struct dma_attrs *attrs)
+static int __iommu_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir, struct dma_attrs *attrs,
+ bool is_coherent)
{
struct scatterlist *s = sg, *dma = sg, *start = sg;
int i, count = 0;
@@ -1321,7 +1311,7 @@ int arm_iommu_map_sg(struct device *dev, struct scatterlist *sg, int nents,
if (s->offset || (size & ~PAGE_MASK) || size + s->length > max) {
if (__map_sg_chunk(dev, start, size, &dma->dma_address,
- dir, attrs) < 0)
+ dir, attrs, is_coherent) < 0)
goto bad_mapping;
dma->dma_address += offset;
@@ -1334,7 +1324,8 @@ int arm_iommu_map_sg(struct device *dev, struct scatterlist *sg, int nents,
}
size += s->length;
}
- if (__map_sg_chunk(dev, start, size, &dma->dma_address, dir, attrs) < 0)
+ if (__map_sg_chunk(dev, start, size, &dma->dma_address, dir, attrs,
+ is_coherent) < 0)
goto bad_mapping;
dma->dma_address += offset;
@@ -1349,17 +1340,44 @@ bad_mapping:
}
/**
- * arm_iommu_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * arm_coherent_iommu_map_sg - map a set of SG buffers for streaming mode DMA
* @dev: valid struct device pointer
* @sg: list of buffers
- * @nents: number of buffers to unmap (same as was passed to dma_map_sg)
- * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
*
- * Unmap a set of streaming mode DMA translations. Again, CPU access
- * rules concerning calls here are the same as for dma_unmap_single().
+ * Map a set of i/o coherent buffers described by scatterlist in streaming
+ * mode for DMA. The scatter gather list elements are merged together (if
+ * possible) and tagged with the appropriate dma address and length. They are
+ * obtained via sg_dma_{address,length}.
*/
-void arm_iommu_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
- enum dma_data_direction dir, struct dma_attrs *attrs)
+int arm_coherent_iommu_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ return __iommu_map_sg(dev, sg, nents, dir, attrs, true);
+}
+
+/**
+ * arm_iommu_map_sg - map a set of SG buffers for streaming mode DMA
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * Map a set of buffers described by scatterlist in streaming mode for DMA.
+ * The scatter gather list elements are merged together (if possible) and
+ * tagged with the appropriate dma address and length. They are obtained via
+ * sg_dma_{address,length}.
+ */
+int arm_iommu_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ return __iommu_map_sg(dev, sg, nents, dir, attrs, false);
+}
+
+static void __iommu_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, struct dma_attrs *attrs,
+ bool is_coherent)
{
struct scatterlist *s;
int i;
@@ -1368,7 +1386,7 @@ void arm_iommu_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
if (sg_dma_len(s))
__iommu_remove_mapping(dev, sg_dma_address(s),
sg_dma_len(s));
- if (!arch_is_coherent() &&
+ if (!is_coherent &&
!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
__dma_page_dev_to_cpu(sg_page(s), s->offset,
s->length, dir);
@@ -1376,6 +1394,38 @@ void arm_iommu_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
}
/**
+ * arm_coherent_iommu_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to unmap (same as was passed to dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ *
+ * Unmap a set of streaming mode DMA translations. Again, CPU access
+ * rules concerning calls here are the same as for dma_unmap_single().
+ */
+void arm_coherent_iommu_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ __iommu_unmap_sg(dev, sg, nents, dir, attrs, true);
+}
+
+/**
+ * arm_iommu_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to unmap (same as was passed to dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ *
+ * Unmap a set of streaming mode DMA translations. Again, CPU access
+ * rules concerning calls here are the same as for dma_unmap_single().
+ */
+void arm_iommu_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ __iommu_unmap_sg(dev, sg, nents, dir, attrs, false);
+}
+
+/**
* arm_iommu_sync_sg_for_cpu
* @dev: valid struct device pointer
* @sg: list of buffers
@@ -1389,8 +1439,7 @@ void arm_iommu_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
int i;
for_each_sg(sg, s, nents, i)
- if (!arch_is_coherent())
- __dma_page_dev_to_cpu(sg_page(s), s->offset, s->length, dir);
+ __dma_page_dev_to_cpu(sg_page(s), s->offset, s->length, dir);
}
@@ -1408,22 +1457,21 @@ void arm_iommu_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
int i;
for_each_sg(sg, s, nents, i)
- if (!arch_is_coherent())
- __dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
+ __dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
}
/**
- * arm_iommu_map_page
+ * arm_coherent_iommu_map_page
* @dev: valid struct device pointer
* @page: page that buffer resides in
* @offset: offset into page for start of buffer
* @size: size of buffer to map
* @dir: DMA transfer direction
*
- * IOMMU aware version of arm_dma_map_page()
+ * Coherent IOMMU aware version of arm_dma_map_page()
*/
-static dma_addr_t arm_iommu_map_page(struct device *dev, struct page *page,
+static dma_addr_t arm_coherent_iommu_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
@@ -1431,9 +1479,6 @@ static dma_addr_t arm_iommu_map_page(struct device *dev, struct page *page,
dma_addr_t dma_addr;
int ret, len = PAGE_ALIGN(size + offset);
- if (!arch_is_coherent() && !dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
- __dma_page_cpu_to_dev(page, offset, size, dir);
-
dma_addr = __alloc_iova(mapping, len);
if (dma_addr == DMA_ERROR_CODE)
return dma_addr;
@@ -1449,6 +1494,52 @@ fail:
}
/**
+ * arm_iommu_map_page
+ * @dev: valid struct device pointer
+ * @page: page that buffer resides in
+ * @offset: offset into page for start of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * IOMMU aware version of arm_dma_map_page()
+ */
+static dma_addr_t arm_iommu_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+ __dma_page_cpu_to_dev(page, offset, size, dir);
+
+ return arm_coherent_iommu_map_page(dev, page, offset, size, dir, attrs);
+}
+
+/**
+ * arm_coherent_iommu_unmap_page
+ * @dev: valid struct device pointer
+ * @handle: DMA address of buffer
+ * @size: size of buffer (same as passed to dma_map_page)
+ * @dir: DMA transfer direction (same as passed to dma_map_page)
+ *
+ * Coherent IOMMU aware version of arm_dma_unmap_page()
+ */
+static void arm_coherent_iommu_unmap_page(struct device *dev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+ dma_addr_t iova = handle & PAGE_MASK;
+ struct page *page = phys_to_page(iommu_iova_to_phys(mapping->domain, iova));
+ int offset = handle & ~PAGE_MASK;
+ int len = PAGE_ALIGN(size + offset);
+
+ if (!iova)
+ return;
+
+ iommu_unmap(mapping->domain, iova, len);
+ __free_iova(mapping, iova, len);
+}
+
+/**
* arm_iommu_unmap_page
* @dev: valid struct device pointer
* @handle: DMA address of buffer
@@ -1470,7 +1561,7 @@ static void arm_iommu_unmap_page(struct device *dev, dma_addr_t handle,
if (!iova)
return;
- if (!arch_is_coherent() && !dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+ if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
__dma_page_dev_to_cpu(page, offset, size, dir);
iommu_unmap(mapping->domain, iova, len);
@@ -1488,8 +1579,7 @@ static void arm_iommu_sync_single_for_cpu(struct device *dev,
if (!iova)
return;
- if (!arch_is_coherent())
- __dma_page_dev_to_cpu(page, offset, size, dir);
+ __dma_page_dev_to_cpu(page, offset, size, dir);
}
static void arm_iommu_sync_single_for_device(struct device *dev,
@@ -1523,6 +1613,19 @@ struct dma_map_ops iommu_ops = {
.sync_sg_for_device = arm_iommu_sync_sg_for_device,
};
+struct dma_map_ops iommu_coherent_ops = {
+ .alloc = arm_iommu_alloc_attrs,
+ .free = arm_iommu_free_attrs,
+ .mmap = arm_iommu_mmap_attrs,
+ .get_sgtable = arm_iommu_get_sgtable,
+
+ .map_page = arm_coherent_iommu_map_page,
+ .unmap_page = arm_coherent_iommu_unmap_page,
+
+ .map_sg = arm_coherent_iommu_map_sg,
+ .unmap_sg = arm_coherent_iommu_unmap_sg,
+};
+
/**
* arm_iommu_create_mapping
* @bus: pointer to the bus holding the client device (for IOMMU calls)
--
1.7.9.5
More information about the linux-arm-kernel
mailing list