1 /* SPDX-License-Identifier: GPL-2.0 */
3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4 * Copyright (C) 2019-2020 Linaro Ltd.
9 #include <linux/types.h>
10 #include <linux/refcount.h>
11 #include <linux/completion.h>
12 #include <linux/dma-direction.h>
23 struct gsi_trans_pool;
26 * struct gsi_trans - a GSI transaction
28 * Most fields in this structure for internal use by the transaction core code:
29 * @links: Links for channel transaction lists by state
31 * @channel_id: Channel number transaction is associated with
32 * @cancelled: If set by the core code, transaction was cancelled
33 * @tre_count: Number of TREs reserved for this transaction
34 * @used: Number of TREs *used* (could be less than tre_count)
35 * @len: Total # of transfer bytes represented in sgl[] (set by core)
36 * @data: Preserved but not touched by the core transaction code
37 * @sgl: An array of scatter/gather entries managed by core code
38 * @info: Array of command information structures (command channel)
39 * @direction: DMA transfer direction (DMA_NONE for commands)
40 * @refcount: Reference count used for destruction
41 * @completion: Completed when the transaction completes
42 * @byte_count: TX channel byte count recorded when transaction committed
43 * @trans_count: Channel transaction count when committed (for BQL accounting)
45 * The size used for some fields in this structure were chosen to ensure
46 * the full structure size is no larger than 128 bytes.
49 struct list_head links; /* gsi_channel lists */
54 bool cancelled; /* true if transaction was cancelled */
56 u8 tre_count; /* # TREs requested */
57 u8 used; /* # entries used in sgl[] */
58 u32 len; /* total # bytes across sgl[] */
61 struct scatterlist *sgl;
62 struct ipa_cmd_info *info; /* array of entries, or null */
63 enum dma_data_direction direction;
66 struct completion completion;
68 u64 byte_count; /* channel byte_count when committed */
69 u64 trans_count; /* channel trans_count when committed */
73 * gsi_trans_pool_init() - Initialize a pool of structures for transactions
74 * @pool: GSI transaction poll pointer
75 * @size: Size of elements in the pool
76 * @count: Minimum number of elements in the pool
77 * @max_alloc: Maximum number of elements allocated at a time from pool
79 * Return: 0 if successful, or a negative error code
81 int gsi_trans_pool_init(struct gsi_trans_pool *pool, size_t size, u32 count,
85 * gsi_trans_pool_alloc() - Allocate one or more elements from a pool
87 * @count: Number of elements to allocate from the pool
89 * Return: Virtual address of element(s) allocated from the pool
91 void *gsi_trans_pool_alloc(struct gsi_trans_pool *pool, u32 count);
94 * gsi_trans_pool_exit() - Inverse of gsi_trans_pool_init()
97 void gsi_trans_pool_exit(struct gsi_trans_pool *pool);
100 * gsi_trans_pool_init_dma() - Initialize a pool of DMA-able structures
101 * @dev: Device used for DMA
102 * @pool: Pool pointer
103 * @size: Size of elements in the pool
104 * @count: Minimum number of elements in the pool
105 * @max_alloc: Maximum number of elements allocated at a time from pool
107 * Return: 0 if successful, or a negative error code
109 * Structures in this pool reside in DMA-coherent memory.
111 int gsi_trans_pool_init_dma(struct device *dev, struct gsi_trans_pool *pool,
112 size_t size, u32 count, u32 max_alloc);
115 * gsi_trans_pool_alloc_dma() - Allocate an element from a DMA pool
116 * @pool: DMA pool pointer
117 * @addr: DMA address "handle" associated with the allocation
119 * Return: Virtual address of element allocated from the pool
121 * Only one element at a time may be allocated from a DMA pool.
123 void *gsi_trans_pool_alloc_dma(struct gsi_trans_pool *pool, dma_addr_t *addr);
126 * gsi_trans_pool_exit_dma() - Inverse of gsi_trans_pool_init_dma()
127 * @dev: Device used for DMA
128 * @pool: Pool pointer
130 void gsi_trans_pool_exit_dma(struct device *dev, struct gsi_trans_pool *pool);
133 * gsi_channel_trans_alloc() - Allocate a GSI transaction on a channel
135 * @channel_id: Channel the transaction is associated with
136 * @tre_count: Number of elements in the transaction
137 * @direction: DMA direction for entire SGL (or DMA_NONE)
139 * Return: A GSI transaction structure, or a null pointer if all
140 * available transactions are in use
142 struct gsi_trans *gsi_channel_trans_alloc(struct gsi *gsi, u32 channel_id,
144 enum dma_data_direction direction);
147 * gsi_trans_free() - Free a previously-allocated GSI transaction
148 * @trans: Transaction to be freed
150 void gsi_trans_free(struct gsi_trans *trans);
153 * gsi_trans_cmd_add() - Add an immediate command to a transaction
154 * @trans: Transaction
155 * @buf: Buffer pointer for command payload
156 * @size: Number of bytes in buffer
157 * @addr: DMA address for payload
158 * @direction: Direction of DMA transfer (or DMA_NONE if none required)
159 * @opcode: IPA immediate command opcode
161 void gsi_trans_cmd_add(struct gsi_trans *trans, void *buf, u32 size,
162 dma_addr_t addr, enum dma_data_direction direction,
163 enum ipa_cmd_opcode opcode);
166 * gsi_trans_page_add() - Add a page transfer to a transaction
167 * @trans: Transaction
168 * @page: Page pointer
169 * @size: Number of bytes (starting at offset) to transfer
170 * @offset: Offset within page for start of transfer
172 int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size,
176 * gsi_trans_skb_add() - Add a socket transfer to a transaction
177 * @trans: Transaction
178 * @skb: Socket buffer for transfer (outbound)
180 * Return: 0, or -EMSGSIZE if socket data won't fit in transaction.
182 int gsi_trans_skb_add(struct gsi_trans *trans, struct sk_buff *skb);
185 * gsi_trans_commit() - Commit a GSI transaction
186 * @trans: Transaction to commit
187 * @ring_db: Whether to tell the hardware about these queued transfers
189 void gsi_trans_commit(struct gsi_trans *trans, bool ring_db);
192 * gsi_trans_commit_wait() - Commit a GSI transaction and wait for it
194 * @trans: Transaction to commit
196 void gsi_trans_commit_wait(struct gsi_trans *trans);
199 * gsi_trans_commit_wait_timeout() - Commit a GSI transaction and wait for
200 * it to complete, with timeout
201 * @trans: Transaction to commit
202 * @timeout: Timeout period (in milliseconds)
204 int gsi_trans_commit_wait_timeout(struct gsi_trans *trans,
205 unsigned long timeout);
208 * gsi_trans_read_byte() - Issue a single byte read TRE on a channel
210 * @channel_id: Channel on which to read a byte
211 * @addr: DMA address into which to transfer the one byte
213 * This is not a transaction operation at all. It's defined here because
214 * it needs to be done in coordination with other transaction activity.
216 int gsi_trans_read_byte(struct gsi *gsi, u32 channel_id, dma_addr_t addr);
219 * gsi_trans_read_byte_done() - Clean up after a single byte read TRE
221 * @channel_id: Channel on which byte was read
223 * This function needs to be called to signal that the work related
224 * to reading a byte initiated by gsi_trans_read_byte() is complete.
226 void gsi_trans_read_byte_done(struct gsi *gsi, u32 channel_id);
228 #endif /* _GSI_TRANS_H_ */