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-rw-r--r--include/linux/dmaengine.h161
1 files changed, 153 insertions, 8 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index dad4a68fa009..64461fc64e1b 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -219,6 +219,62 @@ typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t;
* @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.
+ *
+ * Note: the metadata area for the descriptor is no longer valid after the
+ * transfer has been completed (valid up to the point when the completion
+ * callback returns if used).
+ *
+ * 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 area
+ * 4. Read out the metadata 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;
@@ -238,10 +294,12 @@ struct dma_router {
/**
* struct dma_chan - devices supply DMA channels, clients use them
* @device: ptr to the dma device who supplies this channel, always !%NULL
+ * @slave: ptr to the device using this channel
* @cookie: last cookie value returned to client
* @completed_cookie: last completed cookie for this channel
* @chan_id: channel ID for sysfs
* @dev: class device for sysfs
+ * @name: backlink name for sysfs
* @device_node: used to add this to the device chan list
* @local: per-cpu pointer to a struct dma_chan_percpu
* @client_count: how many clients are using this channel
@@ -252,12 +310,14 @@ struct dma_router {
*/
struct dma_chan {
struct dma_device *device;
+ struct device *slave;
dma_cookie_t cookie;
dma_cookie_t completed_cookie;
/* sysfs */
int chan_id;
struct dma_chan_dev *dev;
+ const char *name;
struct list_head device_node;
struct dma_chan_percpu __percpu *local;
@@ -475,19 +535,36 @@ struct dmaengine_unmap_data {
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---
* @cookie: tracking cookie for this transaction, set to -EBUSY if
* this tx is sitting on a dependency list
* @flags: flags to augment operation preparation, control completion, and
- * communicate status
+ * communicate status
* @phys: physical address of the descriptor
* @chan: target channel for this operation
* @tx_submit: accept the descriptor, assign ordered cookie and mark the
* 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
@@ -504,6 +581,8 @@ struct dma_async_tx_descriptor {
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;
@@ -611,11 +690,13 @@ static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descr
* @residue: the remaining number of bytes left to transmit
* on the selected transfer for states DMA_IN_PROGRESS and
* DMA_PAUSED if this is implemented in the driver, else 0
+ * @in_flight_bytes: amount of data in bytes cached by the DMA.
*/
struct dma_tx_state {
dma_cookie_t last;
dma_cookie_t used;
u32 residue;
+ u32 in_flight_bytes;
};
/**
@@ -666,6 +747,7 @@ struct dma_filter {
* @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
@@ -674,6 +756,7 @@ struct dma_filter {
* @fill_align: alignment shift for memset operations
* @dev_id: unique device ID
* @dev: struct device reference for dma mapping api
+ * @owner: owner module (automatically set based on the provided dev)
* @src_addr_widths: bit mask of src addr widths the device supports
* Width is specified in bytes, e.g. for a device supporting
* a width of 4 the mask should have BIT(4) set.
@@ -718,15 +801,21 @@ struct dma_filter {
* will just return a simple status code
* @device_issue_pending: push pending transactions to hardware
* @descriptor_reuse: a submitted transfer can be resubmitted after completion
+ * @device_release: called sometime atfer dma_async_device_unregister() is
+ * called and there are no further references to this structure. This
+ * must be implemented to free resources however many existing drivers
+ * do not and are therefore not safe to unbind while in use.
+ *
*/
struct dma_device {
-
+ struct kref ref;
unsigned int chancnt;
unsigned int privatecnt;
struct list_head channels;
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;
@@ -737,6 +826,7 @@ struct dma_device {
int dev_id;
struct device *dev;
+ struct module *owner;
u32 src_addr_widths;
u32 dst_addr_widths;
@@ -800,6 +890,7 @@ struct dma_device {
dma_cookie_t cookie,
struct dma_tx_state *txstate);
void (*device_issue_pending)(struct dma_chan *chan);
+ void (*device_release)(struct dma_device *dev);
};
static inline int dmaengine_slave_config(struct dma_chan *chan,
@@ -902,6 +993,41 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memcpy(
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
@@ -1402,16 +1528,16 @@ static inline int dmaengine_desc_free(struct dma_async_tx_descriptor *desc)
int dma_async_device_register(struct dma_device *device);
int dmaenginem_async_device_register(struct dma_device *device);
void dma_async_device_unregister(struct dma_device *device);
+int dma_async_device_channel_register(struct dma_device *device,
+ struct dma_chan *chan);
+void dma_async_device_channel_unregister(struct dma_device *device,
+ struct dma_chan *chan);
void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
-struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
-struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
#define dma_request_channel(mask, x, y) \
__dma_request_channel(&(mask), x, y, NULL)
-#define dma_request_slave_channel_compat(mask, x, y, dev, name) \
- __dma_request_slave_channel_compat(&(mask), x, y, dev, name)
static inline struct dma_chan
-*__dma_request_slave_channel_compat(const dma_cap_mask_t *mask,
+*dma_request_slave_channel_compat(const dma_cap_mask_t mask,
dma_filter_fn fn, void *fn_param,
struct device *dev, const char *name)
{
@@ -1424,6 +1550,25 @@ static inline struct dma_chan
if (!fn || !fn_param)
return NULL;
- return __dma_request_channel(mask, fn, fn_param, NULL);
+ return __dma_request_channel(&mask, fn, fn_param, NULL);
+}
+
+static inline char *
+dmaengine_get_direction_text(enum dma_transfer_direction dir)
+{
+ switch (dir) {
+ case DMA_DEV_TO_MEM:
+ return "DEV_TO_MEM";
+ case DMA_MEM_TO_DEV:
+ return "MEM_TO_DEV";
+ case DMA_MEM_TO_MEM:
+ return "MEM_TO_MEM";
+ case DMA_DEV_TO_DEV:
+ return "DEV_TO_DEV";
+ default:
+ break;
+ }
+
+ return "invalid";
}
#endif /* DMAENGINE_H */