From ea8c64ace86647260ec4255f483e5844d62af2df Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 10 Jan 2018 16:21:13 +0100 Subject: dma-mapping: move swiotlb arch helpers to a new header phys_to_dma, dma_to_phys and dma_capable are helpers published by architecture code for use of swiotlb and xen-swiotlb only. Drivers are not supposed to use these directly, but use the DMA API instead. Move these to a new asm/dma-direct.h helper, included by a linux/dma-direct.h wrapper that provides the default linear mapping unless the architecture wants to override it. In the MIPS case the existing dma-coherent.h is reused for now as untangling it will take a bit of work. Signed-off-by: Christoph Hellwig Acked-by: Robin Murphy --- include/linux/dma-direct.h | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 include/linux/dma-direct.h (limited to 'include') diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h new file mode 100644 index 000000000000..2cc1b6558944 --- /dev/null +++ b/include/linux/dma-direct.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_DMA_DIRECT_H +#define _LINUX_DMA_DIRECT_H 1 + +#include + +#ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA +#include +#else +static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) +{ + dma_addr_t dev_addr = (dma_addr_t)paddr; + + return dev_addr - ((dma_addr_t)dev->dma_pfn_offset << PAGE_SHIFT); +} + +static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr) +{ + phys_addr_t paddr = (phys_addr_t)dev_addr; + + return paddr + ((phys_addr_t)dev->dma_pfn_offset << PAGE_SHIFT); +} + +static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) +{ + if (!dev->dma_mask) + return false; + + return addr + size - 1 <= *dev->dma_mask; +} +#endif /* !CONFIG_ARCH_HAS_PHYS_TO_DMA */ +#endif /* _LINUX_DMA_DIRECT_H */ -- cgit v1.2.3