diff options
Diffstat (limited to 'drivers/of/platform.c')
| -rw-r--r-- | drivers/of/platform.c | 65 |
1 files changed, 59 insertions, 6 deletions
diff --git a/drivers/of/platform.c b/drivers/of/platform.c index bd47fbc53dc9..4e91583a3908 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -189,6 +189,64 @@ struct platform_device *of_device_alloc(struct device_node *np, EXPORT_SYMBOL(of_device_alloc); /** + * of_dma_configure - Setup DMA configuration + * @dev: Device to apply DMA configuration + * + * Try to get devices's DMA configuration from DT and update it + * accordingly. + * + * In case if platform code need to use own special DMA configuration,it + * can use Platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE event + * to fix up DMA configuration. + */ +static void of_dma_configure(struct platform_device *pdev) +{ + u64 dma_addr, paddr, size; + int ret; + struct device *dev = &pdev->dev; + +#if defined(CONFIG_MICROBLAZE) + pdev->archdata.dma_mask = 0xffffffffUL; +#endif + + /* + * Set default dma-mask to 32 bit. Drivers are expected to setup + * the correct supported dma_mask. + */ + dev->coherent_dma_mask = DMA_BIT_MASK(32); + + /* + * Set it to coherent_dma_mask by default if the architecture + * code has not set it. + */ + if (!dev->dma_mask) + dev->dma_mask = &dev->coherent_dma_mask; + + /* + * if dma-coherent property exist, call arch hook to setup + * dma coherent operations. + */ + if (of_dma_is_coherent(dev->of_node)) { + set_arch_dma_coherent_ops(dev); + dev_dbg(dev, "device is dma coherent\n"); + } + + /* + * if dma-ranges property doesn't exist - just return else + * setup the dma offset + */ + ret = of_dma_get_range(dev->of_node, &dma_addr, &paddr, &size); + if (ret < 0) { + dev_dbg(dev, "no dma range information to setup\n"); + return; + } + + /* DMA ranges found. Calculate and set dma_pfn_offset */ + dev->dma_pfn_offset = PFN_DOWN(paddr - dma_addr); + dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", dev->dma_pfn_offset); +} + +/** * of_platform_device_create_pdata - Alloc, initialize and register an of_device * @np: pointer to node to create device for * @bus_id: name to assign device @@ -213,12 +271,7 @@ static struct platform_device *of_platform_device_create_pdata( if (!dev) return NULL; -#if defined(CONFIG_MICROBLAZE) - dev->archdata.dma_mask = 0xffffffffUL; -#endif - dev->dev.coherent_dma_mask = DMA_BIT_MASK(32); - if (!dev->dev.dma_mask) - dev->dev.dma_mask = &dev->dev.coherent_dma_mask; + of_dma_configure(dev); dev->dev.bus = &platform_bus_type; dev->dev.platform_data = platform_data; |