diff options
| -rw-r--r-- | include/linux/device.h | 3 | ||||
| -rw-r--r-- | lib/dma-direct.c | 6 |
2 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/device.h b/include/linux/device.h index 563077d1cdc1..00b6c3b42437 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -904,6 +904,8 @@ struct dev_links_info { * @offline: Set after successful invocation of bus type's .offline(). * @of_node_reused: Set if the device-tree node is shared with an ancestor * device. + * @dma_32bit_limit: bridge limited to 32bit DMA even if the device itself + * indicates support for a higher limit in the dma_mask field. * * At the lowest level, every device in a Linux system is represented by an * instance of struct device. The device structure contains the information @@ -992,6 +994,7 @@ struct device { bool offline_disabled:1; bool offline:1; bool of_node_reused:1; + bool dma_32bit_limit:1; }; static inline struct device *kobj_to_dev(struct kobject *kobj) diff --git a/lib/dma-direct.c b/lib/dma-direct.c index b824eb218782..a48f94eff62e 100644 --- a/lib/dma-direct.c +++ b/lib/dma-direct.c @@ -172,6 +172,12 @@ int dma_direct_supported(struct device *dev, u64 mask) if (mask < DMA_BIT_MASK(32)) return 0; #endif + /* + * Various PCI/PCIe bridges have broken support for > 32bit DMA even + * if the device itself might support it. + */ + if (dev->dma_32bit_limit && mask > DMA_BIT_MASK(32)) + return 0; return 1; } |