From 3f03396918962b2f8b888d02b23cd1e0c88bf5e5 Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Tue, 24 May 2016 09:16:06 +0200 Subject: media: vb2-dma-contig: add helper for setting dma max seg size Add a helper function for device drivers to set DMA's max_seg_size. Setting it to largest possible value lets DMA-mapping API always create contiguous mappings in DMA address space. This is essential for all devices, which use dma-contig videobuf2 memory allocator and shared buffers. Till now, the only case when vb2-dma-contig really 'worked' was a case where userspace provided USERPTR buffer, which was in fact mmaped contiguous buffer from the other v4l2/drm device. Also DMABUF made of contiguous buffer worked only when its exporter did not split it into several chunks in the scatter-list. Any other buffer failed, regardless of the arch/platform used and the presence of the IOMMU of the device bus. This patch provides interface to fix this issue. Signed-off-by: Marek Szyprowski Signed-off-by: Sylwester Nawrocki --- include/media/videobuf2-dma-contig.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/media/videobuf2-dma-contig.h b/include/media/videobuf2-dma-contig.h index 2087c9a68be3..f7dc8401817e 100644 --- a/include/media/videobuf2-dma-contig.h +++ b/include/media/videobuf2-dma-contig.h @@ -35,6 +35,8 @@ static inline void *vb2_dma_contig_init_ctx(struct device *dev) } void vb2_dma_contig_cleanup_ctx(void *alloc_ctx); +int vb2_dma_contig_set_max_seg_size(struct device *dev, unsigned int size); +void vb2_dma_contig_clear_max_seg_size(struct device *dev); extern const struct vb2_mem_ops vb2_dma_contig_memops; -- cgit v1.2.3 From 59ce4039727ef408769ab0e1263ece893abe22bb Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Tue, 24 May 2016 15:31:24 +0200 Subject: of: reserved_mem: add support for using more than one region for given device This patch allows device drivers to initialize more than one reserved memory region assigned to given device. When driver needs to use more than one reserved memory region, it should allocate child devices and initialize regions by index for each of its child devices. Signed-off-by: Marek Szyprowski Acked-by: Rob Herring Signed-off-by: Sylwester Nawrocki --- include/linux/of_reserved_mem.h | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h index ad2f67054372..1779cda99ef7 100644 --- a/include/linux/of_reserved_mem.h +++ b/include/linux/of_reserved_mem.h @@ -1,7 +1,8 @@ #ifndef __OF_RESERVED_MEM_H #define __OF_RESERVED_MEM_H -struct device; +#include + struct of_phandle_args; struct reserved_mem_ops; @@ -28,14 +29,17 @@ typedef int (*reservedmem_of_init_fn)(struct reserved_mem *rmem); _OF_DECLARE(reservedmem, name, compat, init, reservedmem_of_init_fn) #ifdef CONFIG_OF_RESERVED_MEM -int of_reserved_mem_device_init(struct device *dev); + +int of_reserved_mem_device_init_by_idx(struct device *dev, + struct device_node *np, int idx); void of_reserved_mem_device_release(struct device *dev); void fdt_init_reserved_mem(void); void fdt_reserved_mem_save_node(unsigned long node, const char *uname, phys_addr_t base, phys_addr_t size); #else -static inline int of_reserved_mem_device_init(struct device *dev) +static inline int of_reserved_mem_device_init_by_idx(struct device *dev, + struct device_node *np, int idx) { return -ENOSYS; } @@ -46,4 +50,19 @@ static inline void fdt_reserved_mem_save_node(unsigned long node, const char *uname, phys_addr_t base, phys_addr_t size) { } #endif +/** + * of_reserved_mem_device_init() - assign reserved memory region to given device + * @dev: Pointer to the device to configure + * + * This function assigns respective DMA-mapping operations based on the first + * reserved memory region specified by 'memory-region' property in device tree + * node of the given device. + * + * Returns error code or zero on success. + */ +static inline int of_reserved_mem_device_init(struct device *dev) +{ + return of_reserved_mem_device_init_by_idx(dev, dev->of_node, 0); +} + #endif /* __OF_RESERVED_MEM_H */ -- cgit v1.2.3