Hi All,
The DMA mapping works great on our PowerPC machines currently. It was a
long way to get the new DMA mapping code to work successfully on our
PowerPC machines.
P L E A S E don't modify the good working DMA mapping code. There are
many other topics which needs improvements. For us (first level + second
level support) it is really laborious to find your problematic code and
patch it. It takes a long time to find the problematic code because we
have to do it besides our main work.
P L E A S E test your code on PowerPC machines before you add it to the
mainline vanilla kernel.
Thanks,
Christian
On Tue, Mar 24, 2020 at 12:00:09PM +0530, Aneesh Kumar K.V wrote:
> dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
> unsigned long offset, size_t size, enum dma_data_direction dir,
> unsigned long attrs)
> {
> phys_addr_t phys = page_to_phys(page) + offset;
> dma_addr_t dma_addr = phys_to_dma(dev, phys);
>
> if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
> return iommu_map(dev, phys, size, dir, attrs);
>
> return DMA_MAPPING_ERROR;
If powerpc hardware / firmware people really come up with crap that
stupid you'll have to handle it yourself and will always pay the
indirect call penality.
