diff options
| -rw-r--r-- | drivers/of/device.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/drivers/of/device.c b/drivers/of/device.c index 28e743888402..20c1332a0018 100644 --- a/drivers/of/device.c +++ b/drivers/of/device.c @@ -90,10 +90,11 @@ void of_dma_configure(struct device *dev, struct device_node *np) struct iommu_ops *iommu; /* - * Set default dma-mask to 32 bit. Drivers are expected to setup - * the correct supported dma_mask. + * Set default coherent_dma_mask to 32 bit. Drivers are expected to + * setup the correct supported mask. */ - dev->coherent_dma_mask = DMA_BIT_MASK(32); + if (!dev->coherent_dma_mask) + dev->coherent_dma_mask = DMA_BIT_MASK(32); /* * Set it to coherent_dma_mask by default if the architecture @@ -128,6 +129,15 @@ void of_dma_configure(struct device *dev, struct device_node *np) dev->dma_pfn_offset = offset; + /* + * Limit coherent and dma mask based on size and default mask + * set by the driver. + */ + dev->coherent_dma_mask = min(dev->coherent_dma_mask, + DMA_BIT_MASK(ilog2(dma_addr + size))); + *dev->dma_mask = min((*dev->dma_mask), + DMA_BIT_MASK(ilog2(dma_addr + size))); + coherent = of_dma_is_coherent(np); dev_dbg(dev, "device is%sdma coherent\n", coherent ? " " : " not "); |