1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. 4 * Copyright (C) 2019-2020 Linaro Ltd. 5 */ 6 #ifndef _GSI_TRANS_H_ 7 #define _GSI_TRANS_H_ 8 9 #include <linux/types.h> 10 #include <linux/refcount.h> 11 #include <linux/completion.h> 12 #include <linux/dma-direction.h> 13 14 #include "ipa_cmd.h" 15 16 struct scatterlist; 17 struct device; 18 struct sk_buff; 19 20 struct gsi; 21 struct gsi_trans; 22 struct gsi_trans_pool; 23 24 /** 25 * struct gsi_trans - a GSI transaction 26 * 27 * Most fields in this structure for internal use by the transaction core code: 28 * @links: Links for channel transaction lists by state 29 * @gsi: GSI pointer 30 * @channel_id: Channel number transaction is associated with 31 * @cancelled: If set by the core code, transaction was cancelled 32 * @tre_count: Number of TREs reserved for this transaction 33 * @used: Number of TREs *used* (could be less than tre_count) 34 * @len: Total # of transfer bytes represented in sgl[] (set by core) 35 * @data: Preserved but not touched by the core transaction code 36 * @sgl: An array of scatter/gather entries managed by core code 37 * @info: Array of command information structures (command channel) 38 * @direction: DMA transfer direction (DMA_NONE for commands) 39 * @refcount: Reference count used for destruction 40 * @completion: Completed when the transaction completes 41 * @byte_count: TX channel byte count recorded when transaction committed 42 * @trans_count: Channel transaction count when committed (for BQL accounting) 43 * 44 * The size used for some fields in this structure were chosen to ensure 45 * the full structure size is no larger than 128 bytes. 46 */ 47 struct gsi_trans { 48 struct list_head links; /* gsi_channel lists */ 49 50 struct gsi *gsi; 51 u8 channel_id; 52 53 bool cancelled; /* true if transaction was cancelled */ 54 55 u8 tre_count; /* # TREs requested */ 56 u8 used; /* # entries used in sgl[] */ 57 u32 len; /* total # bytes across sgl[] */ 58 59 void *data; 60 struct scatterlist *sgl; 61 struct ipa_cmd_info *info; /* array of entries, or null */ 62 enum dma_data_direction direction; 63 64 refcount_t refcount; 65 struct completion completion; 66 67 u64 byte_count; /* channel byte_count when committed */ 68 u64 trans_count; /* channel trans_count when committed */ 69 }; 70 71 /** 72 * gsi_trans_pool_init() - Initialize a pool of structures for transactions 73 * @gsi: GSI pointer 74 * @size: Size of elements in the pool 75 * @count: Minimum number of elements in the pool 76 * @max_alloc: Maximum number of elements allocated at a time from pool 77 * 78 * @Return: 0 if successful, or a negative error code 79 */ 80 int gsi_trans_pool_init(struct gsi_trans_pool *pool, size_t size, u32 count, 81 u32 max_alloc); 82 83 /** 84 * gsi_trans_pool_alloc() - Allocate one or more elements from a pool 85 * @pool: Pool pointer 86 * @count: Number of elements to allocate from the pool 87 * 88 * @Return: Virtual address of element(s) allocated from the pool 89 */ 90 void *gsi_trans_pool_alloc(struct gsi_trans_pool *pool, u32 count); 91 92 /** 93 * gsi_trans_pool_exit() - Inverse of gsi_trans_pool_init() 94 * @pool: Pool pointer 95 */ 96 void gsi_trans_pool_exit(struct gsi_trans_pool *pool); 97 98 /** 99 * gsi_trans_pool_init_dma() - Initialize a pool of DMA-able structures 100 * @dev: Device used for DMA 101 * @pool: Pool pointer 102 * @size: Size of elements in the pool 103 * @count: Minimum number of elements in the pool 104 * @max_alloc: Maximum number of elements allocated at a time from pool 105 * 106 * @Return: 0 if successful, or a negative error code 107 * 108 * Structures in this pool reside in DMA-coherent memory. 109 */ 110 int gsi_trans_pool_init_dma(struct device *dev, struct gsi_trans_pool *pool, 111 size_t size, u32 count, u32 max_alloc); 112 113 /** 114 * gsi_trans_pool_alloc_dma() - Allocate an element from a DMA pool 115 * @pool: DMA pool pointer 116 * @addr: DMA address "handle" associated with the allocation 117 * 118 * @Return: Virtual address of element allocated from the pool 119 * 120 * Only one element at a time may be allocated from a DMA pool. 121 */ 122 void *gsi_trans_pool_alloc_dma(struct gsi_trans_pool *pool, dma_addr_t *addr); 123 124 /** 125 * gsi_trans_pool_exit() - Inverse of gsi_trans_pool_init() 126 * @pool: Pool pointer 127 */ 128 void gsi_trans_pool_exit_dma(struct device *dev, struct gsi_trans_pool *pool); 129 130 /** 131 * gsi_channel_trans_alloc() - Allocate a GSI transaction on a channel 132 * @gsi: GSI pointer 133 * @channel_id: Channel the transaction is associated with 134 * @tre_count: Number of elements in the transaction 135 * @direction: DMA direction for entire SGL (or DMA_NONE) 136 * 137 * @Return: A GSI transaction structure, or a null pointer if all 138 * available transactions are in use 139 */ 140 struct gsi_trans *gsi_channel_trans_alloc(struct gsi *gsi, u32 channel_id, 141 u32 tre_count, 142 enum dma_data_direction direction); 143 144 /** 145 * gsi_trans_free() - Free a previously-allocated GSI transaction 146 * @trans: Transaction to be freed 147 */ 148 void gsi_trans_free(struct gsi_trans *trans); 149 150 /** 151 * gsi_trans_cmd_add() - Add an immediate command to a transaction 152 * @trans: Transaction 153 * @buf: Buffer pointer for command payload 154 * @size: Number of bytes in buffer 155 * @addr: DMA address for payload 156 * @direction: Direction of DMA transfer (or DMA_NONE if none required) 157 * @opcode: IPA immediate command opcode 158 */ 159 void gsi_trans_cmd_add(struct gsi_trans *trans, void *buf, u32 size, 160 dma_addr_t addr, enum dma_data_direction direction, 161 enum ipa_cmd_opcode opcode); 162 163 /** 164 * gsi_trans_page_add() - Add a page transfer to a transaction 165 * @trans: Transaction 166 * @page: Page pointer 167 * @size: Number of bytes (starting at offset) to transfer 168 * @offset: Offset within page for start of transfer 169 */ 170 int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size, 171 u32 offset); 172 173 /** 174 * gsi_trans_skb_add() - Add a socket transfer to a transaction 175 * @trans: Transaction 176 * @skb: Socket buffer for transfer (outbound) 177 * 178 * @Return: 0, or -EMSGSIZE if socket data won't fit in transaction. 179 */ 180 int gsi_trans_skb_add(struct gsi_trans *trans, struct sk_buff *skb); 181 182 /** 183 * gsi_trans_commit() - Commit a GSI transaction 184 * @trans: Transaction to commit 185 * @ring_db: Whether to tell the hardware about these queued transfers 186 */ 187 void gsi_trans_commit(struct gsi_trans *trans, bool ring_db); 188 189 /** 190 * gsi_trans_commit_wait() - Commit a GSI transaction and wait for it 191 * to complete 192 * @trans: Transaction to commit 193 */ 194 void gsi_trans_commit_wait(struct gsi_trans *trans); 195 196 /** 197 * gsi_trans_commit_wait_timeout() - Commit a GSI transaction and wait for 198 * it to complete, with timeout 199 * @trans: Transaction to commit 200 * @timeout: Timeout period (in milliseconds) 201 */ 202 int gsi_trans_commit_wait_timeout(struct gsi_trans *trans, 203 unsigned long timeout); 204 205 /** 206 * gsi_trans_read_byte() - Issue a single byte read TRE on a channel 207 * @gsi: GSI pointer 208 * @channel_id: Channel on which to read a byte 209 * @addr: DMA address into which to transfer the one byte 210 * 211 * This is not a transaction operation at all. It's defined here because 212 * it needs to be done in coordination with other transaction activity. 213 */ 214 int gsi_trans_read_byte(struct gsi *gsi, u32 channel_id, dma_addr_t addr); 215 216 /** 217 * gsi_trans_read_byte_done() - Clean up after a single byte read TRE 218 * @gsi: GSI pointer 219 * @channel_id: Channel on which byte was read 220 * 221 * This function needs to be called to signal that the work related 222 * to reading a byte initiated by gsi_trans_read_byte() is complete. 223 */ 224 void gsi_trans_read_byte_done(struct gsi *gsi, u32 channel_id); 225 226 #endif /* _GSI_TRANS_H_ */ 227