Re: [PATCH v2] arc: Implement arch-specific dma_map_ops.mmap

2016-11-15 Thread Ramiro Oliveira
On 11/3/2016 3:06 PM, Alexey Brodkin wrote: > We used to use generic implementation of dma_map_ops.mmap which is > dma_common_mmap() but that only worked for simpler cached mappings when > vaddr = paddr. > > If a driver requests uncached DMA buffer kernel maps it to virtual > address so that MMU

Re: [PATCH v2] arc: Implement arch-specific dma_map_ops.mmap

2016-11-15 Thread Ramiro Oliveira
On 11/3/2016 3:06 PM, Alexey Brodkin wrote: > We used to use generic implementation of dma_map_ops.mmap which is > dma_common_mmap() but that only worked for simpler cached mappings when > vaddr = paddr. > > If a driver requests uncached DMA buffer kernel maps it to virtual > address so that MMU

RE: [PATCH v2] arc: Implement arch-specific dma_map_ops.mmap

2016-11-03 Thread Alexey Brodkin
@vger.kernel.org; Vineet Gupta > <vineet.gup...@synopsys.com>; Marek Szyprowski > <m.szyprow...@samsung.com>; sta...@vger.kernel.org > Subject: Re: [PATCH v2] arc: Implement arch-specific dma_map_ops.mmap > > On 11/03/2016 08:06 AM, Alexey Brodkin wrote: > > We use

RE: [PATCH v2] arc: Implement arch-specific dma_map_ops.mmap

2016-11-03 Thread Alexey Brodkin
t; ; Marek Szyprowski > ; sta...@vger.kernel.org > Subject: Re: [PATCH v2] arc: Implement arch-specific dma_map_ops.mmap > > On 11/03/2016 08:06 AM, Alexey Brodkin wrote: > > We used to use generic implementation of dma_map_ops.mmap which is > > dma_common_mmap() but that

Re: [PATCH v2] arc: Implement arch-specific dma_map_ops.mmap

2016-11-03 Thread Vineet Gupta
On 11/03/2016 08:06 AM, Alexey Brodkin wrote: > We used to use generic implementation of dma_map_ops.mmap which is > dma_common_mmap() but that only worked for simpler cached mappings when > vaddr = paddr. > > If a driver requests uncached DMA buffer kernel maps it to virtual > address so that

Re: [PATCH v2] arc: Implement arch-specific dma_map_ops.mmap

2016-11-03 Thread Vineet Gupta
On 11/03/2016 08:06 AM, Alexey Brodkin wrote: > We used to use generic implementation of dma_map_ops.mmap which is > dma_common_mmap() but that only worked for simpler cached mappings when > vaddr = paddr. > > If a driver requests uncached DMA buffer kernel maps it to virtual > address so that

[PATCH v2] arc: Implement arch-specific dma_map_ops.mmap

2016-11-03 Thread Alexey Brodkin
We used to use generic implementation of dma_map_ops.mmap which is dma_common_mmap() but that only worked for simpler cached mappings when vaddr = paddr. If a driver requests uncached DMA buffer kernel maps it to virtual address so that MMU gets involved and page uncached status takes into

[PATCH v2] arc: Implement arch-specific dma_map_ops.mmap

2016-11-03 Thread Alexey Brodkin
We used to use generic implementation of dma_map_ops.mmap which is dma_common_mmap() but that only worked for simpler cached mappings when vaddr = paddr. If a driver requests uncached DMA buffer kernel maps it to virtual address so that MMU gets involved and page uncached status takes into