Hi,
I noticed there is currently no CMA support for AArch64. Is this already on someone's TODO list or is this still open?
Thanks, Laura
Hi Laura,
On Wed, Nov 20, 2013 at 09:41:18PM +0000, Laura Abbott wrote:
I noticed there is currently no CMA support for AArch64. Is this already on someone's TODO list or is this still open?
It's more like a wish list but there were other things that took priority. The arm64 DMA mapping code currently only supports swiotlb and our next plan is for IOMMU mapping. But I would like parts of the DMA IOMMU code under arch/arm to be made into a library (similar to the lib/swiotlb.c) so that other architectures can easily make use of it.
Yet another feature is DMA cache coherency management (primarily streaming DMA) and I have a patch but I want this driven via DT rather than drivers or SoC code calling set_dma_ops explicitly (the bindings definition is work in progress).
Anyway, I think the CMA support wouldn't interfere much with the above and could be merged. If you have time, please feel free to send some patches ;).
On Thu, Nov 21, 2013 at 12:06:00PM +0000, Catalin Marinas wrote:
Hi Laura,
On Wed, Nov 20, 2013 at 09:41:18PM +0000, Laura Abbott wrote:
I noticed there is currently no CMA support for AArch64. Is this already on someone's TODO list or is this still open?
It's more like a wish list but there were other things that took priority. The arm64 DMA mapping code currently only supports swiotlb and our next plan is for IOMMU mapping. But I would like parts of the DMA IOMMU code under arch/arm to be made into a library (similar to the lib/swiotlb.c) so that other architectures can easily make use of it.
If you're referring to dmabounce.c, that's a 100% no-way-ever-even-if- hell-freezes-over NACK.
On Thu, Nov 21, 2013 at 12:11:35PM +0000, Russell King - ARM Linux wrote:
On Thu, Nov 21, 2013 at 12:06:00PM +0000, Catalin Marinas wrote:
On Wed, Nov 20, 2013 at 09:41:18PM +0000, Laura Abbott wrote:
I noticed there is currently no CMA support for AArch64. Is this already on someone's TODO list or is this still open?
It's more like a wish list but there were other things that took priority. The arm64 DMA mapping code currently only supports swiotlb and our next plan is for IOMMU mapping. But I would like parts of the DMA IOMMU code under arch/arm to be made into a library (similar to the lib/swiotlb.c) so that other architectures can easily make use of it.
If you're referring to dmabounce.c, that's a 100% no-way-ever-even-if- hell-freezes-over NACK.
Does dmabounce.c implement IOMMU support? I'm talking about functions like __alloc_iova, __iommu_create_mapping etc.
The generic swiotlb code has enough bouncing capabilities for my needs.
Yet another feature is DMA cache coherency management (primarily streaming DMA) and I have a patch but I want this driven via DT rather than drivers or SoC code calling set_dma_ops explicitly (the bindings definition is work in progress).
Hi Catalin,
Is there the plan or the progress about this part (streaming DMA)? :)
On Wed, Feb 26, 2014 at 09:50:35AM +0000, Hwang Chih-Chyuan wrote:
Yet another feature is DMA cache coherency management (primarily streaming DMA) and I have a patch but I want this driven via DT rather than drivers or SoC code calling set_dma_ops explicitly (the bindings definition is work in progress).
Is there the plan or the progress about this part (streaming DMA)? :)
You can grab a patch here:
https://git.kernel.org/cgit/linux/kernel/git/cmarinas/linux-aarch64.git/comm...
However, I'd like to see some progress on defining the system topology via DT rather than driver manually setting the dma ops. Dave Martin is looking at this but I don't have an ETA yet.
linaro-mm-sig@lists.linaro.org
-
Catalin Marinas -
Hwang Chih-Chyuan -
Laura Abbott -
Russell King - ARM Linux