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-rw-r--r--arch/openrisc/kernel/dma.c109
1 files changed, 73 insertions, 36 deletions
diff --git a/arch/openrisc/kernel/dma.c b/arch/openrisc/kernel/dma.c
index f1c8ee2895d..0b77ddb1ee0 100644
--- a/arch/openrisc/kernel/dma.c
+++ b/arch/openrisc/kernel/dma.c
@@ -21,13 +21,16 @@
#include <linux/dma-mapping.h>
#include <linux/dma-debug.h>
+#include <linux/export.h>
+#include <linux/dma-attrs.h>
#include <asm/cpuinfo.h>
#include <asm/spr_defs.h>
#include <asm/tlbflush.h>
-static int page_set_nocache(pte_t *pte, unsigned long addr,
- unsigned long next, struct mm_walk *walk)
+static int
+page_set_nocache(pte_t *pte, unsigned long addr,
+ unsigned long next, struct mm_walk *walk)
{
unsigned long cl;
@@ -46,8 +49,9 @@ static int page_set_nocache(pte_t *pte, unsigned long addr,
return 0;
}
-static int page_clear_nocache(pte_t *pte, unsigned long addr,
- unsigned long next, struct mm_walk *walk)
+static int
+page_clear_nocache(pte_t *pte, unsigned long addr,
+ unsigned long next, struct mm_walk *walk)
{
pte_val(*pte) &= ~_PAGE_CI;
@@ -67,9 +71,19 @@ static int page_clear_nocache(pte_t *pte, unsigned long addr,
* cache-inhibit bit on those pages, and makes sure that the pages are
* flushed out of the cache before they are used.
*
+ * If the NON_CONSISTENT attribute is set, then this function just
+ * returns "normal", cachable memory.
+ *
+ * There are additional flags WEAK_ORDERING and WRITE_COMBINE to take
+ * into consideration here, too. All current known implementations of
+ * the OR1K support only strongly ordered memory accesses, so that flag
+ * is being ignored for now; uncached but write-combined memory is a
+ * missing feature of the OR1K.
*/
-void *or1k_dma_alloc_coherent(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t gfp)
+static void *
+or1k_dma_alloc(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp,
+ struct dma_attrs *attrs)
{
unsigned long va;
void *page;
@@ -87,20 +101,23 @@ void *or1k_dma_alloc_coherent(struct device *dev, size_t size,
va = (unsigned long)page;
- /*
- * We need to iterate through the pages, clearing the dcache for
- * them and setting the cache-inhibit bit.
- */
- if (walk_page_range(va, va + size, &walk)) {
- free_pages_exact(page, size);
- return NULL;
+ if (!dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs)) {
+ /*
+ * We need to iterate through the pages, clearing the dcache for
+ * them and setting the cache-inhibit bit.
+ */
+ if (walk_page_range(va, va + size, &walk)) {
+ free_pages_exact(page, size);
+ return NULL;
+ }
}
return (void *)va;
}
-void or1k_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_handle)
+static void
+or1k_dma_free(struct device *dev, size_t size, void *vaddr,
+ dma_addr_t dma_handle, struct dma_attrs *attrs)
{
unsigned long va = (unsigned long)vaddr;
struct mm_walk walk = {
@@ -108,16 +125,19 @@ void or1k_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
.mm = &init_mm
};
- /* walk_page_range shouldn't be able to fail here */
- WARN_ON(walk_page_range(va, va + size, &walk));
+ if (!dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs)) {
+ /* walk_page_range shouldn't be able to fail here */
+ WARN_ON(walk_page_range(va, va + size, &walk));
+ }
free_pages_exact(vaddr, size);
}
-dma_addr_t or1k_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction dir,
- struct dma_attrs *attrs)
+static dma_addr_t
+or1k_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir,
+ struct dma_attrs *attrs)
{
unsigned long cl;
dma_addr_t addr = page_to_phys(page) + offset;
@@ -147,16 +167,18 @@ dma_addr_t or1k_map_page(struct device *dev, struct page *page,
return addr;
}
-void or1k_unmap_page(struct device *dev, dma_addr_t dma_handle,
- size_t size, enum dma_data_direction dir,
- struct dma_attrs *attrs)
+static void
+or1k_unmap_page(struct device *dev, dma_addr_t dma_handle,
+ size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
{
/* Nothing special to do here... */
}
-int or1k_map_sg(struct device *dev, struct scatterlist *sg,
- int nents, enum dma_data_direction dir,
- struct dma_attrs *attrs)
+static int
+or1k_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
{
struct scatterlist *s;
int i;
@@ -169,9 +191,10 @@ int or1k_map_sg(struct device *dev, struct scatterlist *sg,
return nents;
}
-void or1k_unmap_sg(struct device *dev, struct scatterlist *sg,
- int nents, enum dma_data_direction dir,
- struct dma_attrs *attrs)
+static void
+or1k_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
{
struct scatterlist *s;
int i;
@@ -181,9 +204,10 @@ void or1k_unmap_sg(struct device *dev, struct scatterlist *sg,
}
}
-void or1k_sync_single_for_cpu(struct device *dev,
- dma_addr_t dma_handle, size_t size,
- enum dma_data_direction dir)
+static void
+or1k_sync_single_for_cpu(struct device *dev,
+ dma_addr_t dma_handle, size_t size,
+ enum dma_data_direction dir)
{
unsigned long cl;
dma_addr_t addr = dma_handle;
@@ -193,9 +217,10 @@ void or1k_sync_single_for_cpu(struct device *dev,
mtspr(SPR_DCBIR, cl);
}
-void or1k_sync_single_for_device(struct device *dev,
- dma_addr_t dma_handle, size_t size,
- enum dma_data_direction dir)
+static void
+or1k_sync_single_for_device(struct device *dev,
+ dma_addr_t dma_handle, size_t size,
+ enum dma_data_direction dir)
{
unsigned long cl;
dma_addr_t addr = dma_handle;
@@ -205,6 +230,18 @@ void or1k_sync_single_for_device(struct device *dev,
mtspr(SPR_DCBFR, cl);
}
+struct dma_map_ops or1k_dma_map_ops = {
+ .alloc = or1k_dma_alloc,
+ .free = or1k_dma_free,
+ .map_page = or1k_map_page,
+ .unmap_page = or1k_unmap_page,
+ .map_sg = or1k_map_sg,
+ .unmap_sg = or1k_unmap_sg,
+ .sync_single_for_cpu = or1k_sync_single_for_cpu,
+ .sync_single_for_device = or1k_sync_single_for_device,
+};
+EXPORT_SYMBOL(or1k_dma_map_ops);
+
/* Number of entries preallocated for DMA-API debugging */
#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)