powerpc/dma: Add optional platform override of dma_set_mask()

Some platforms may want to override dma_set_mask() to take into
account some specific "features" such as the availability of
a direct-map window in addition to an iommu.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt 2010-08-30 19:23:52 +00:00
parent cab175f9fa
commit 5b6e9ff6de
3 changed files with 22 additions and 13 deletions

View File

@ -127,19 +127,7 @@ static inline int dma_supported(struct device *dev, u64 mask)
return dma_ops->dma_supported(dev, mask);
}
static inline int dma_set_mask(struct device *dev, u64 dma_mask)
{
struct dma_map_ops *dma_ops = get_dma_ops(dev);
if (unlikely(dma_ops == NULL))
return -EIO;
if (dma_ops->set_dma_mask != NULL)
return dma_ops->set_dma_mask(dev, dma_mask);
if (!dev->dma_mask || !dma_supported(dev, dma_mask))
return -EIO;
*dev->dma_mask = dma_mask;
return 0;
}
extern int dma_set_mask(struct device *dev, u64 dma_mask);
static inline void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t flag)

View File

@ -102,6 +102,9 @@ struct machdep_calls {
void (*pci_dma_dev_setup)(struct pci_dev *dev);
void (*pci_dma_bus_setup)(struct pci_bus *bus);
/* Platform set_dma_mask override */
int (*dma_set_mask)(struct device *dev, u64 dma_mask);
int (*probe)(void);
void (*setup_arch)(void); /* Optional, may be NULL */
void (*init_early)(void);

View File

@ -12,6 +12,7 @@
#include <linux/memblock.h>
#include <asm/bug.h>
#include <asm/abs_addr.h>
#include <asm/machdep.h>
/*
* Generic direct DMA implementation
@ -154,6 +155,23 @@ EXPORT_SYMBOL(dma_direct_ops);
#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
int dma_set_mask(struct device *dev, u64 dma_mask)
{
struct dma_map_ops *dma_ops = get_dma_ops(dev);
if (ppc_md.dma_set_mask)
return ppc_md.dma_set_mask(dev, dma_mask);
if (unlikely(dma_ops == NULL))
return -EIO;
if (dma_ops->set_dma_mask != NULL)
return dma_ops->set_dma_mask(dev, dma_mask);
if (!dev->dma_mask || !dma_supported(dev, dma_mask))
return -EIO;
*dev->dma_mask = dma_mask;
return 0;
}
EXPORT_SYMBOL(dma_set_mask);
static int __init dma_init(void)
{
dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);