Re: [PATCH] powerpc/npu-dma: Remove NPU DMA ops

2018-10-30 Thread Michael Ellerman
Christoph Hellwig writes: > On Wed, Oct 31, 2018 at 12:09:29AM +1100, Benjamin Herrenschmidt wrote: >> On Tue, 2018-10-30 at 13:58 +0100, Christoph Hellwig wrote: >> > Please take my patch instead. We have a kernel polcity to not keep >> > dead code around, and everyone including Linus and the a

Re: [PATCH] powerpc/npu-dma: Remove NPU DMA ops

2018-10-30 Thread Christoph Hellwig
On Wed, Oct 31, 2018 at 12:09:29AM +1100, Benjamin Herrenschmidt wrote: > On Tue, 2018-10-30 at 13:58 +0100, Christoph Hellwig wrote: > > Please take my patch instead. We have a kernel polcity to not keep > > dead code around, and everyone including Linus and the attending IBMers > > confirmed thi

Re: [PATCH] powerpc/npu-dma: Remove NPU DMA ops

2018-10-30 Thread Benjamin Herrenschmidt
On Tue, 2018-10-30 at 13:58 +0100, Christoph Hellwig wrote: > Please take my patch instead. We have a kernel polcity to not keep > dead code around, and everyone including Linus and the attending IBMers > confirmed this. Let's call a cat a cat ... ;-) It's not *dead* code. It's code that is used

Re: [PATCH] powerpc/npu-dma: Remove NPU DMA ops

2018-10-30 Thread Christoph Hellwig
Please take my patch instead. We have a kernel polcity to not keep dead code around, and everyone including Linus and the attending IBMers confirmed this. On Tue, Oct 30, 2018 at 10:02:03PM +1100, Alistair Popple wrote: > The NPU IOMMU is setup to mirror the parent PCIe device IOMMU > setup. Ther

[PATCH] powerpc/npu-dma: Remove NPU DMA ops

2018-10-30 Thread Alistair Popple
The NPU IOMMU is setup to mirror the parent PCIe device IOMMU setup. Therefore it does not make sense to call dma operations such as dma_map_page, etc. directly on these devices. The existing dma-ops simply print a warning if they are ever called, however this is unnecessary and the warnings are li