[RFC v1 PATCH 1/2] of/pci: add of_pci_dma_configure() update dma configuration

[Arnd Bergmann]

On Tuesday 23 December 2014 12:42:05 Murali Karicheri wrote:
> > here.
> 
> Arnd,
> 
> I guess so. Besides we need to keep the default coherent dma mask to 
> 32bit 0xffffffffull as well to work on Keystone and also in sync with 
> current defaults used in pci_device_add() so that we don't break this 
> behavior.
> 
> Here is the summary of changes need to make on top of my existing patch.
> 
> 1. of_dma_configure() - change size = dev->coherent_dma_mask to size = 
> dev->coherent_dma_mask + 1. This is a new patch to fix existing code.

ok

> 2. Do the above change to of_pci_dma_configure() as well.

ok

> 3. in arch_setup_dma_ops() update the DMA mask to min((*dev->dma_mask), 
> dma_base + size - 1) as
> 
> 
> diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
> index c17f6a9..88b4769 100644
> --- a/arch/arm/mm/dma-mapping.c
> +++ b/arch/arm/mm/dma-mapping.c
> @@ -2053,8 +2053,13 @@ void arch_setup_dma_ops(struct device *dev, u64 
> dma_base, u64 size,
>   {
>          struct dma_map_ops *dma_ops;
> 
> +
> +       *dev->dma_mask = min((*dev->dma_mask), (dma_base + size - 1));
> 
> I have tested this on keystone and it works fine with rootfs on PCI SATA 
> harddisk. I will be doing more tests with this change. If you are in 
> agreement with the above changes, I will re-spin the patch to accomodate 
> them and send v1 of the same.

Ok, sounds good. I noticed that you did not put Russell into the Cc list
for the emails. Please do so when you send it again, as he may have some
additional comments.

	Arnd