Messages in this thread | | | Date | Mon, 22 Dec 2014 17:40:30 -0500 | From | Murali Karicheri <> | Subject | Re: [RFC v1 PATCH 1/2] of/pci: add of_pci_dma_configure() update dma configuration |
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On 12/22/2014 05:24 PM, Arnd Bergmann wrote: > On Monday 22 December 2014 16:40:43 Murali Karicheri wrote: >>>> +++ b/arch/arm/mm/dma-mapping.c >>>> @@ -2052,9 +2052,10 @@ void arch_setup_dma_ops(struct device *dev, u64 >>>> dma_base, u64 size, >>>> struct iommu_ops *iommu, bool coherent) >>>> { >>>> struct dma_map_ops *dma_ops; >>>> + u64 temp_size = min((*(dev->dma_mask) + 1), size); >>>> >>>> dev->archdata.dma_coherent = coherent; >>>> - if (arm_setup_iommu_dma_ops(dev, dma_base, size, iommu)) >>>> + if (arm_setup_iommu_dma_ops(dev, dma_base, temp_size, iommu)) >>>> >>>> If you agree, I will post v1 of the patch with these updates. Let me >>>> know. I did some basic tests on Keystone with these changes and it works >>>> fine. >>> >>> It's not exactly what I meant. My main point was that we need to limit >>> dev->dma_mask to (size-1) here, but you are not touching that. >> >> if you mean overriding the dev->dma_mask to min((*dev->dma_mask), >> size-1), then I am getting the error "Coherent DMA mask 0x7fffffff (pfn >> 0x780000-0x800000) covers a smaller range of system memory than the DMA >> zone pfn 0x0-0x880000) when the devices on Keystone tries to set the dma >> mask. Something wrong and I need to look into the code. > > Right, it sounds like the offset was applied incorrectly at some point. > > What are the DMA zone size and the phys-offset? 2G and 0x8_0000_0000. This limit the usable DMA size to 2G on Keystone, I believe you shouldn't be limiting the dma mask to size-1 in this case, right? The DT setup the dma-range to have a size of 2G (0x80000000).
Murali > > Arnd
-- Murali Karicheri Linux Kernel, Texas Instruments
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