diff options
| -rw-r--r-- | include/linux/device.h | 11 | ||||
| -rw-r--r-- | include/linux/dma-mapping.h | 15 |
2 files changed, 26 insertions, 0 deletions
diff --git a/include/linux/device.h b/include/linux/device.h index 479c0b31593c..2258d89bf523 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -410,6 +410,15 @@ extern int devres_release_group(struct device *dev, void *id); extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp); extern void devm_kfree(struct device *dev, void *p); +struct device_dma_parameters { + /* + * a low level driver may set these to teach IOMMU code about + * sg limitations. + */ + unsigned int max_segment_size; + unsigned long segment_boundary_mask; +}; + struct device { struct klist klist_children; struct klist_node knode_parent; /* node in sibling list */ @@ -445,6 +454,8 @@ struct device { 64 bit addresses for consistent allocations such descriptors. */ + struct device_dma_parameters *dma_parms; + struct list_head dma_pools; /* dma pools (if dma'ble) */ struct dma_coherent_mem *dma_mem; /* internal for coherent mem diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 4470950892be..df3a3610caf0 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -60,6 +60,21 @@ static inline int is_device_dma_capable(struct device *dev) extern u64 dma_get_required_mask(struct device *dev); +static inline unsigned int dma_get_max_seg_size(struct device *dev) +{ + return dev->dma_parms ? dev->dma_parms->max_segment_size : 65536; +} + +static inline unsigned int dma_set_max_seg_size(struct device *dev, + unsigned int size) +{ + if (dev->dma_parms) { + dev->dma_parms->max_segment_size = size; + return 0; + } else + return -EIO; +} + /* flags for the coherent memory api */ #define DMA_MEMORY_MAP 0x01 #define DMA_MEMORY_IO 0x02 |