diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index 1d26eeb6b5f6..6b20128fab8a 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -277,14 +277,26 @@ and parameters are provided to do partial page mapping, it is recommended that you never use these unless you really know what the cache width is. +dma_addr_t +dma_map_resource(struct device *dev, phys_addr_t phys_addr, size_t size, + enum dma_data_direction dir, unsigned long attrs) + +void +dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size, + enum dma_data_direction dir, unsigned long attrs) + +API for mapping and unmapping for MMIO resources. All the notes and +warnings for the other mapping APIs apply here. The API should only be +used to map device MMIO resources, mapping of RAM is not permitted. + int dma_mapping_error(struct device *dev, dma_addr_t dma_addr) -In some circumstances dma_map_single() and dma_map_page() will fail to create -a mapping. A driver can check for these errors by testing the returned -DMA address with dma_mapping_error(). A non-zero return value means the mapping -could not be created and the driver should take appropriate action (e.g. -reduce current DMA mapping usage or delay and try again later). +In some circumstances dma_map_single(), dma_map_page() and dma_map_resource() +will fail to create a mapping. A driver can check for these errors by testing +the returned DMA address with dma_mapping_error(). A non-zero return value +means the mapping could not be created and the driver should take appropriate +action (e.g. reduce current DMA mapping usage or delay and try again later). int dma_map_sg(struct device *dev, struct scatterlist *sg, diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index c6834c0cfd1c..746eb29c6f0c 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -2014,6 +2014,63 @@ static void arm_iommu_unmap_page(struct device *dev, dma_addr_t handle, __free_iova(mapping, iova, len); } +/** + * arm_iommu_map_resource - map a device resource for DMA + * @dev: valid struct device pointer + * @phys_addr: physical address of resource + * @size: size of resource to map + * @dir: DMA transfer direction + */ +static dma_addr_t arm_iommu_map_resource(struct device *dev, + phys_addr_t phys_addr, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ + struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev); + dma_addr_t dma_addr; + int ret, prot; + phys_addr_t addr = phys_addr & PAGE_MASK; + unsigned int offset = phys_addr & ~PAGE_MASK; + size_t len = PAGE_ALIGN(size + offset); + + dma_addr = __alloc_iova(mapping, len); + if (dma_addr == DMA_ERROR_CODE) + return dma_addr; + + prot = __dma_direction_to_prot(dir) | IOMMU_MMIO; + + ret = iommu_map(mapping->domain, dma_addr, addr, len, prot); + if (ret < 0) + goto fail; + + return dma_addr + offset; +fail: + __free_iova(mapping, dma_addr, len); + return DMA_ERROR_CODE; +} + +/** + * arm_iommu_unmap_resource - unmap a device DMA resource + * @dev: valid struct device pointer + * @dma_handle: DMA address to resource + * @size: size of resource to map + * @dir: DMA transfer direction + */ +static void arm_iommu_unmap_resource(struct device *dev, dma_addr_t dma_handle, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev); + dma_addr_t iova = dma_handle & PAGE_MASK; + unsigned int offset = dma_handle & ~PAGE_MASK; + size_t len = PAGE_ALIGN(size + offset); + + if (!iova) + return; + + iommu_unmap(mapping->domain, iova, len); + __free_iova(mapping, iova, len); +} + static void arm_iommu_sync_single_for_cpu(struct device *dev, dma_addr_t handle, size_t size, enum dma_data_direction dir) { @@ -2057,6 +2114,9 @@ struct dma_map_ops iommu_ops = { .unmap_sg = arm_iommu_unmap_sg, .sync_sg_for_cpu = arm_iommu_sync_sg_for_cpu, .sync_sg_for_device = arm_iommu_sync_sg_for_device, + + .map_resource = arm_iommu_map_resource, + .unmap_resource = arm_iommu_unmap_resource, }; struct dma_map_ops iommu_coherent_ops = { @@ -2070,6 +2130,9 @@ struct dma_map_ops iommu_coherent_ops = { .map_sg = arm_coherent_iommu_map_sg, .unmap_sg = arm_coherent_iommu_unmap_sg, + + .map_resource = arm_iommu_map_resource, + .unmap_resource = arm_iommu_unmap_resource, }; /** diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index d1defa4646ba..2e441d0ccd79 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -117,15 +117,35 @@ struct rcar_dmac_desc_page { ((PAGE_SIZE - offsetof(struct rcar_dmac_desc_page, chunks)) / \ sizeof(struct rcar_dmac_xfer_chunk)) +/* + * struct rcar_dmac_chan_slave - Slave configuration + * @slave_addr: slave memory address + * @xfer_size: size (in bytes) of hardware transfers + */ +struct rcar_dmac_chan_slave { + phys_addr_t slave_addr; + unsigned int xfer_size; +}; + +/* + * struct rcar_dmac_chan_map - Map of slave device phys to dma address + * @addr: slave dma address + * @dir: direction of mapping + * @slave: slave configuration that is mapped + */ +struct rcar_dmac_chan_map { + dma_addr_t addr; + enum dma_data_direction dir; + struct rcar_dmac_chan_slave slave; +}; + /* * struct rcar_dmac_chan - R-Car Gen2 DMA Controller Channel * @chan: base DMA channel object * @iomem: channel I/O memory base * @index: index of this channel in the controller - * @src_xfer_size: size (in bytes) of hardware transfers on the source side - * @dst_xfer_size: size (in bytes) of hardware transfers on the destination side - * @src_slave_addr: slave source memory address - * @dst_slave_addr: slave destination memory address + * @src: slave memory address and size on the source side + * @dst: slave memory address and size on the destination side * @mid_rid: hardware MID/RID for the DMA client using this channel * @lock: protects the channel CHCR register and the desc members * @desc.free: list of free descriptors @@ -142,10 +162,9 @@ struct rcar_dmac_chan { void __iomem *iomem; unsigned int index; - unsigned int src_xfer_size; - unsigned int dst_xfer_size; - dma_addr_t src_slave_addr; - dma_addr_t dst_slave_addr; + struct rcar_dmac_chan_slave src; + struct rcar_dmac_chan_slave dst; + struct rcar_dmac_chan_map map; int mid_rid; spinlock_t lock; @@ -793,13 +812,13 @@ static void rcar_dmac_chan_configure_desc(struct rcar_dmac_chan *chan, case DMA_DEV_TO_MEM: chcr = RCAR_DMACHCR_DM_INC | RCAR_DMACHCR_SM_FIXED | RCAR_DMACHCR_RS_DMARS; - xfer_size = chan->src_xfer_size; + xfer_size = chan->src.xfer_size; break; case DMA_MEM_TO_DEV: chcr = RCAR_DMACHCR_DM_FIXED | RCAR_DMACHCR_SM_INC | RCAR_DMACHCR_RS_DMARS; - xfer_size = chan->dst_xfer_size; + xfer_size = chan->dst.xfer_size; break; case DMA_MEM_TO_MEM: @@ -1023,13 +1042,65 @@ rcar_dmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dma_dest, DMA_MEM_TO_MEM, flags, false); } +static int rcar_dmac_map_slave_addr(struct dma_chan *chan, + enum dma_transfer_direction dir) +{ + struct rcar_dmac_chan *rchan = to_rcar_dmac_chan(chan); + struct rcar_dmac_chan_map *map = &rchan->map; + phys_addr_t dev_addr; + size_t dev_size; + enum dma_data_direction dev_dir; + + if (dir == DMA_DEV_TO_MEM) { + dev_addr = rchan->src.slave_addr; + dev_size = rchan->src.xfer_size; + dev_dir = DMA_TO_DEVICE; + } else { + dev_addr = rchan->dst.slave_addr; + dev_size = rchan->dst.xfer_size; + dev_dir = DMA_FROM_DEVICE; + } + + /* Reuse current map if possible. */ + if (dev_addr == map->slave.slave_addr && + dev_size == map->slave.xfer_size && + dev_dir == map->dir) + return 0; + + /* Remove old mapping if present. */ + if (map->slave.xfer_size) + dma_unmap_resource(chan->device->dev, map->addr, + map->slave.xfer_size, map->dir, 0); + map->slave.xfer_size = 0; + + /* Create new slave address map. */ + map->addr = dma_map_resource(chan->device->dev, dev_addr, dev_size, + dev_dir, 0); + + if (dma_mapping_error(chan->device->dev, map->addr)) { + dev_err(chan->device->dev, + "chan%u: failed to map %zx@%pap", rchan->index, + dev_size, &dev_addr); + return -EIO; + } + + dev_dbg(chan->device->dev, "chan%u: map %zx@%pap to %pad dir: %s\n", + rchan->index, dev_size, &dev_addr, &map->addr, + dev_dir == DMA_TO_DEVICE ? "DMA_TO_DEVICE" : "DMA_FROM_DEVICE"); + + map->slave.slave_addr = dev_addr; + map->slave.xfer_size = dev_size; + map->dir = dev_dir; + + return 0; +} + static struct dma_async_tx_descriptor * rcar_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction dir, unsigned long flags, void *context) { struct rcar_dmac_chan *rchan = to_rcar_dmac_chan(chan); - dma_addr_t dev_addr; /* Someone calling slave DMA on a generic channel? */ if (rchan->mid_rid < 0 || !sg_len) { @@ -1039,9 +1110,10 @@ rcar_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, return NULL; } - dev_addr = dir == DMA_DEV_TO_MEM - ? rchan->src_slave_addr : rchan->dst_slave_addr; - return rcar_dmac_chan_prep_sg(rchan, sgl, sg_len, dev_addr, + if (rcar_dmac_map_slave_addr(chan, dir)) + return NULL; + + return rcar_dmac_chan_prep_sg(rchan, sgl, sg_len, rchan->map.addr, dir, flags, false); } @@ -1055,7 +1127,6 @@ rcar_dmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, struct rcar_dmac_chan *rchan = to_rcar_dmac_chan(chan); struct dma_async_tx_descriptor *desc; struct scatterlist *sgl; - dma_addr_t dev_addr; unsigned int sg_len; unsigned int i; @@ -1067,6 +1138,9 @@ rcar_dmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, return NULL; } + if (rcar_dmac_map_slave_addr(chan, dir)) + return NULL; + sg_len = buf_len / period_len; if (sg_len > RCAR_DMAC_MAX_SG_LEN) { dev_err(chan->device->dev, @@ -1094,9 +1168,7 @@ rcar_dmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, sg_dma_len(&sgl[i]) = period_len; } - dev_addr = dir == DMA_DEV_TO_MEM - ? rchan->src_slave_addr : rchan->dst_slave_addr; - desc = rcar_dmac_chan_prep_sg(rchan, sgl, sg_len, dev_addr, + desc = rcar_dmac_chan_prep_sg(rchan, sgl, sg_len, rchan->map.addr, dir, flags, true); kfree(sgl); @@ -1112,10 +1184,10 @@ static int rcar_dmac_device_config(struct dma_chan *chan, * We could lock this, but you shouldn't be configuring the * channel, while using it... */ - rchan->src_slave_addr = cfg->src_addr; - rchan->dst_slave_addr = cfg->dst_addr; - rchan->src_xfer_size = cfg->src_addr_width; - rchan->dst_xfer_size = cfg->dst_addr_width; + rchan->src.slave_addr = cfg->src_addr; + rchan->dst.slave_addr = cfg->dst_addr; + rchan->src.xfer_size = cfg->src_addr_width; + rchan->dst.xfer_size = cfg->dst_addr_width; return 0; } diff --git a/include/linux/dma-debug.h b/include/linux/dma-debug.h index fe8cb610deac..c7d844f09c3a 100644 --- a/include/linux/dma-debug.h +++ b/include/linux/dma-debug.h @@ -56,6 +56,13 @@ extern void debug_dma_alloc_coherent(struct device *dev, size_t size, extern void debug_dma_free_coherent(struct device *dev, size_t size, void *virt, dma_addr_t addr); +extern void debug_dma_map_resource(struct device *dev, phys_addr_t addr, + size_t size, int direction, + dma_addr_t dma_addr); + +extern void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr, + size_t size, int direction); + extern void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size, int direction); @@ -141,6 +148,18 @@ static inline void debug_dma_free_coherent(struct device *dev, size_t size, { } +static inline void debug_dma_map_resource(struct device *dev, phys_addr_t addr, + size_t size, int direction, + dma_addr_t dma_addr) +{ +} + +static inline void debug_dma_unmap_resource(struct device *dev, + dma_addr_t dma_addr, size_t size, + int direction) +{ +} + static inline void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size, int direction) diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 66533e18276c..642cb4c7ad37 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -95,6 +95,12 @@ struct dma_map_ops { struct scatterlist *sg, int nents, enum dma_data_direction dir, unsigned long attrs); + dma_addr_t (*map_resource)(struct device *dev, phys_addr_t phys_addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs); + void (*unmap_resource)(struct device *dev, dma_addr_t dma_handle, + size_t size, enum dma_data_direction dir, + unsigned long attrs); void (*sync_single_for_cpu)(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir); @@ -258,6 +264,41 @@ static inline void dma_unmap_page(struct device *dev, dma_addr_t addr, debug_dma_unmap_page(dev, addr, size, dir, false); } +static inline dma_addr_t dma_map_resource(struct device *dev, + phys_addr_t phys_addr, + size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + struct dma_map_ops *ops = get_dma_ops(dev); + dma_addr_t addr; + + BUG_ON(!valid_dma_direction(dir)); + + /* Don't allow RAM to be mapped */ + BUG_ON(pfn_valid(PHYS_PFN(phys_addr))); + + addr = phys_addr; + if (ops->map_resource) + addr = ops->map_resource(dev, phys_addr, size, dir, attrs); + + debug_dma_map_resource(dev, phys_addr, size, dir, addr); + + return addr; +} + +static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + if (ops->unmap_resource) + ops->unmap_resource(dev, addr, size, dir, attrs); + debug_dma_unmap_resource(dev, addr, size, dir); +} + static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size, enum dma_data_direction dir) diff --git a/lib/dma-debug.c b/lib/dma-debug.c index fcfa1939ac41..59e75863bfa0 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -43,6 +43,7 @@ enum { dma_debug_page, dma_debug_sg, dma_debug_coherent, + dma_debug_resource, }; enum map_err_types { @@ -150,8 +151,9 @@ static const char *const maperr2str[] = { [MAP_ERR_CHECKED] = "dma map error checked", }; -static const char *type2name[4] = { "single", "page", - "scather-gather", "coherent" }; +static const char *type2name[5] = { "single", "page", + "scather-gather", "coherent", + "resource" }; static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE", "DMA_FROM_DEVICE", "DMA_NONE" }; @@ -399,6 +401,9 @@ static void hash_bucket_del(struct dma_debug_entry *entry) static unsigned long long phys_addr(struct dma_debug_entry *entry) { + if (entry->type == dma_debug_resource) + return __pfn_to_phys(entry->pfn) + entry->offset; + return page_to_phys(pfn_to_page(entry->pfn)) + entry->offset; } @@ -1495,6 +1500,49 @@ void debug_dma_free_coherent(struct device *dev, size_t size, } EXPORT_SYMBOL(debug_dma_free_coherent); +void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size, + int direction, dma_addr_t dma_addr) +{ + struct dma_debug_entry *entry; + + if (unlikely(dma_debug_disabled())) + return; + + entry = dma_entry_alloc(); + if (!entry) + return; + + entry->type = dma_debug_resource; + entry->dev = dev; + entry->pfn = PHYS_PFN(addr); + entry->offset = offset_in_page(addr); + entry->size = size; + entry->dev_addr = dma_addr; + entry->direction = direction; + entry->map_err_type = MAP_ERR_NOT_CHECKED; + + add_dma_entry(entry); +} +EXPORT_SYMBOL(debug_dma_map_resource); + +void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr, + size_t size, int direction) +{ + struct dma_debug_entry ref = { + .type = dma_debug_resource, + .dev = dev, + .dev_addr = dma_addr, + .size = size, + .direction = direction, + }; + + if (unlikely(dma_debug_disabled())) + return; + + check_unmap(&ref); +} +EXPORT_SYMBOL(debug_dma_unmap_resource); + void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size, int direction) {