index d49ec5c31944863137f044b4046808dab60fe4ea..d33a953c9b55fcfe6ba9c4a0471fdabbc70051b2 100644 (file)
* @bytes_transferred: byte counter
*/
+/**
+ * enum dma_desc_metadata_mode - per descriptor metadata mode types supported
+ * @DESC_METADATA_CLIENT - the metadata buffer is allocated/provided by the
+ * client driver and it is attached (via the dmaengine_desc_attach_metadata()
+ * helper) to the descriptor.
+ *
+ * Client drivers interested to use this mode can follow:
+ * - DMA_MEM_TO_DEV / DEV_MEM_TO_MEM:
+ * 1. prepare the descriptor (dmaengine_prep_*)
+ * construct the metadata in the client's buffer
+ * 2. use dmaengine_desc_attach_metadata() to attach the buffer to the
+ * descriptor
+ * 3. submit the transfer
+ * - DMA_DEV_TO_MEM:
+ * 1. prepare the descriptor (dmaengine_prep_*)
+ * 2. use dmaengine_desc_attach_metadata() to attach the buffer to the
+ * descriptor
+ * 3. submit the transfer
+ * 4. when the transfer is completed, the metadata should be available in the
+ * attached buffer
+ *
+ * @DESC_METADATA_ENGINE - the metadata buffer is allocated/managed by the DMA
+ * driver. The client driver can ask for the pointer, maximum size and the
+ * currently used size of the metadata and can directly update or read it.
+ * dmaengine_desc_get_metadata_ptr() and dmaengine_desc_set_metadata_len() is
+ * provided as helper functions.
+ *
+ * Client drivers interested to use this mode can follow:
+ * - DMA_MEM_TO_DEV / DEV_MEM_TO_MEM:
+ * 1. prepare the descriptor (dmaengine_prep_*)
+ * 2. use dmaengine_desc_get_metadata_ptr() to get the pointer to the engine's
+ * metadata area
+ * 3. update the metadata at the pointer
+ * 4. use dmaengine_desc_set_metadata_len() to tell the DMA engine the amount
+ * of data the client has placed into the metadata buffer
+ * 5. submit the transfer
+ * - DMA_DEV_TO_MEM:
+ * 1. prepare the descriptor (dmaengine_prep_*)
+ * 2. submit the transfer
+ * 3. on transfer completion, use dmaengine_desc_get_metadata_ptr() to get the
+ * pointer to the engine's metadata are
+ * 4. Read out the metadate from the pointer
+ *
+ * Note: the two mode is not compatible and clients must use one mode for a
+ * descriptor.
+ */
+enum dma_desc_metadata_mode {
+ DESC_METADATA_NONE = 0,
+ DESC_METADATA_CLIENT = BIT(0),
+ DESC_METADATA_ENGINE = BIT(1),
+};
+
struct dma_chan_percpu {
/* stats */
unsigned long memcpy_count;
dma_addr_t addr[0];
};
+struct dma_async_tx_descriptor;
+
+struct dma_descriptor_metadata_ops {
+ int (*attach)(struct dma_async_tx_descriptor *desc, void *data,
+ size_t len);
+
+ void *(*get_ptr)(struct dma_async_tx_descriptor *desc,
+ size_t *payload_len, size_t *max_len);
+ int (*set_len)(struct dma_async_tx_descriptor *desc,
+ size_t payload_len);
+};
+
/**
* struct dma_async_tx_descriptor - async transaction descriptor
* ---dma generic offload fields---
* descriptor pending. To be pushed on .issue_pending() call
* @callback: routine to call after this operation is complete
* @callback_param: general parameter to pass to the callback routine
+ * @desc_metadata_mode: core managed metadata mode to protect mixed use of
+ * DESC_METADATA_CLIENT or DESC_METADATA_ENGINE. Otherwise
+ * DESC_METADATA_NONE
+ * @metadata_ops: DMA driver provided metadata mode ops, need to be set by the
+ * DMA driver if metadata mode is supported with the descriptor
* ---async_tx api specific fields---
* @next: at completion submit this descriptor
* @parent: pointer to the next level up in the dependency chain
dma_async_tx_callback_result callback_result;
void *callback_param;
struct dmaengine_unmap_data *unmap;
+ enum dma_desc_metadata_mode desc_metadata_mode;
+ struct dma_descriptor_metadata_ops *metadata_ops;
#ifdef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH
struct dma_async_tx_descriptor *next;
struct dma_async_tx_descriptor *parent;
* @global_node: list_head for global dma_device_list
* @filter: information for device/slave to filter function/param mapping
* @cap_mask: one or more dma_capability flags
+ * @desc_metadata_modes: supported metadata modes by the DMA device
* @max_xor: maximum number of xor sources, 0 if no capability
* @max_pq: maximum number of PQ sources and PQ-continue capability
* @copy_align: alignment shift for memcpy operations
struct list_head global_node;
struct dma_filter filter;
dma_cap_mask_t cap_mask;
+ enum dma_desc_metadata_mode desc_metadata_modes;
unsigned short max_xor;
unsigned short max_pq;
enum dmaengine_alignment copy_align;
len, flags);
}
+static inline bool dmaengine_is_metadata_mode_supported(struct dma_chan *chan,
+ enum dma_desc_metadata_mode mode)
+{
+ if (!chan)
+ return false;
+
+ return !!(chan->device->desc_metadata_modes & mode);
+}
+
+#ifdef CONFIG_DMA_ENGINE
+int dmaengine_desc_attach_metadata(struct dma_async_tx_descriptor *desc,
+ void *data, size_t len);
+void *dmaengine_desc_get_metadata_ptr(struct dma_async_tx_descriptor *desc,
+ size_t *payload_len, size_t *max_len);
+int dmaengine_desc_set_metadata_len(struct dma_async_tx_descriptor *desc,
+ size_t payload_len);
+#else /* CONFIG_DMA_ENGINE */
+static inline int dmaengine_desc_attach_metadata(
+ struct dma_async_tx_descriptor *desc, void *data, size_t len)
+{
+ return -EINVAL;
+}
+static inline void *dmaengine_desc_get_metadata_ptr(
+ struct dma_async_tx_descriptor *desc, size_t *payload_len,
+ size_t *max_len)
+{
+ return NULL;
+}
+static inline int dmaengine_desc_set_metadata_len(
+ struct dma_async_tx_descriptor *desc, size_t payload_len)
+{
+ return -EINVAL;
+}
+#endif /* CONFIG_DMA_ENGINE */
+
/**
* dmaengine_terminate_all() - Terminate all active DMA transfers
* @chan: The channel for which to terminate the transfers