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 page; 17 struct scatterlist; 18 struct device; 19 struct sk_buff; 20 21 struct gsi; 22 struct gsi_trans; 23 struct gsi_trans_pool; 24 25 /* Maximum number of TREs in an IPA immediate command transaction */ 26 #define IPA_COMMAND_TRANS_TRE_MAX 8 27 28 /** 29 * struct gsi_trans - a GSI transaction 30 * 31 * Most fields in this structure for internal use by the transaction core code: 32 * @links: Links for channel transaction lists by state 33 * @gsi: GSI pointer 34 * @channel_id: Channel number transaction is associated with 35 * @cancelled: If set by the core code, transaction was cancelled 36 * @rsvd_count: Number of TREs reserved for this transaction 37 * @used_count: Number of TREs *used* (could be less than rsvd_count) 38 * @len: Number of bytes sent or received by the transaction 39 * @data: Preserved but not touched by the core transaction code 40 * @cmd_opcode: Array of command opcodes (command channel only) 41 * @sgl: An array of scatter/gather entries managed by core code 42 * @direction: DMA transfer direction (DMA_NONE for commands) 43 * @refcount: Reference count used for destruction 44 * @completion: Completed when the transaction completes 45 * @byte_count: TX channel byte count recorded when transaction committed 46 * @trans_count: Channel transaction count when committed (for BQL accounting) 47 * 48 * The @len field is set when the transaction is committed. For RX 49 * transactions it is updated later to reflect the actual number of bytes 50 * received. 51 */ 52 struct gsi_trans { 53 struct list_head links; /* gsi_channel lists */ 54 55 struct gsi *gsi; 56 u8 channel_id; 57 58 bool cancelled; /* true if transaction was cancelled */ 59 60 u8 rsvd_count; /* # TREs requested */ 61 u8 used_count; /* # entries used in sgl[] */ 62 u32 len; /* total # bytes across sgl[] */ 63 64 union { 65 void *data; 66 u8 cmd_opcode[IPA_COMMAND_TRANS_TRE_MAX]; 67 }; 68 struct scatterlist *sgl; 69 enum dma_data_direction direction; 70 71 refcount_t refcount; 72 struct completion completion; 73 74 u64 byte_count; /* channel byte_count when committed */ 75 u64 trans_count; /* channel trans_count when committed */ 76 }; 77 78 /** 79 * gsi_trans_pool_init() - Initialize a pool of structures for transactions 80 * @pool: GSI transaction poll pointer 81 * @size: Size of elements in the pool 82 * @count: Minimum number of elements in the pool 83 * @max_alloc: Maximum number of elements allocated at a time from pool 84 * 85 * Return: 0 if successful, or a negative error code 86 */ 87 int gsi_trans_pool_init(struct gsi_trans_pool *pool, size_t size, u32 count, 88 u32 max_alloc); 89 90 /** 91 * gsi_trans_pool_alloc() - Allocate one or more elements from a pool 92 * @pool: Pool pointer 93 * @count: Number of elements to allocate from the pool 94 * 95 * Return: Virtual address of element(s) allocated from the pool 96 */ 97 void *gsi_trans_pool_alloc(struct gsi_trans_pool *pool, u32 count); 98 99 /** 100 * gsi_trans_pool_exit() - Inverse of gsi_trans_pool_init() 101 * @pool: Pool pointer 102 */ 103 void gsi_trans_pool_exit(struct gsi_trans_pool *pool); 104 105 /** 106 * gsi_trans_pool_init_dma() - Initialize a pool of DMA-able structures 107 * @dev: Device used for DMA 108 * @pool: Pool pointer 109 * @size: Size of elements in the pool 110 * @count: Minimum number of elements in the pool 111 * @max_alloc: Maximum number of elements allocated at a time from pool 112 * 113 * Return: 0 if successful, or a negative error code 114 * 115 * Structures in this pool reside in DMA-coherent memory. 116 */ 117 int gsi_trans_pool_init_dma(struct device *dev, struct gsi_trans_pool *pool, 118 size_t size, u32 count, u32 max_alloc); 119 120 /** 121 * gsi_trans_pool_alloc_dma() - Allocate an element from a DMA pool 122 * @pool: DMA pool pointer 123 * @addr: DMA address "handle" associated with the allocation 124 * 125 * Return: Virtual address of element allocated from the pool 126 * 127 * Only one element at a time may be allocated from a DMA pool. 128 */ 129 void *gsi_trans_pool_alloc_dma(struct gsi_trans_pool *pool, dma_addr_t *addr); 130 131 /** 132 * gsi_trans_pool_exit_dma() - Inverse of gsi_trans_pool_init_dma() 133 * @dev: Device used for DMA 134 * @pool: Pool pointer 135 */ 136 void gsi_trans_pool_exit_dma(struct device *dev, struct gsi_trans_pool *pool); 137 138 /** 139 * gsi_channel_trans_idle() - Return whether no transactions are allocated 140 * @gsi: GSI pointer 141 * @channel_id: Channel the transaction is associated with 142 * 143 * Return: True if no transactions are allocated, false otherwise 144 * 145 */ 146 bool gsi_channel_trans_idle(struct gsi *gsi, u32 channel_id); 147 148 /** 149 * gsi_channel_trans_alloc() - Allocate a GSI transaction on a channel 150 * @gsi: GSI pointer 151 * @channel_id: Channel the transaction is associated with 152 * @tre_count: Number of elements in the transaction 153 * @direction: DMA direction for entire SGL (or DMA_NONE) 154 * 155 * Return: A GSI transaction structure, or a null pointer if all 156 * available transactions are in use 157 */ 158 struct gsi_trans *gsi_channel_trans_alloc(struct gsi *gsi, u32 channel_id, 159 u32 tre_count, 160 enum dma_data_direction direction); 161 162 /** 163 * gsi_trans_free() - Free a previously-allocated GSI transaction 164 * @trans: Transaction to be freed 165 */ 166 void gsi_trans_free(struct gsi_trans *trans); 167 168 /** 169 * gsi_trans_cmd_add() - Add an immediate command to a transaction 170 * @trans: Transaction 171 * @buf: Buffer pointer for command payload 172 * @size: Number of bytes in buffer 173 * @addr: DMA address for payload 174 * @opcode: IPA immediate command opcode 175 */ 176 void gsi_trans_cmd_add(struct gsi_trans *trans, void *buf, u32 size, 177 dma_addr_t addr, enum ipa_cmd_opcode opcode); 178 179 /** 180 * gsi_trans_page_add() - Add a page transfer to a transaction 181 * @trans: Transaction 182 * @page: Page pointer 183 * @size: Number of bytes (starting at offset) to transfer 184 * @offset: Offset within page for start of transfer 185 */ 186 int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size, 187 u32 offset); 188 189 /** 190 * gsi_trans_skb_add() - Add a socket transfer to a transaction 191 * @trans: Transaction 192 * @skb: Socket buffer for transfer (outbound) 193 * 194 * Return: 0, or -EMSGSIZE if socket data won't fit in transaction. 195 */ 196 int gsi_trans_skb_add(struct gsi_trans *trans, struct sk_buff *skb); 197 198 /** 199 * gsi_trans_commit() - Commit a GSI transaction 200 * @trans: Transaction to commit 201 * @ring_db: Whether to tell the hardware about these queued transfers 202 */ 203 void gsi_trans_commit(struct gsi_trans *trans, bool ring_db); 204 205 /** 206 * gsi_trans_commit_wait() - Commit a GSI transaction and wait for it 207 * to complete 208 * @trans: Transaction to commit 209 */ 210 void gsi_trans_commit_wait(struct gsi_trans *trans); 211 212 /** 213 * gsi_trans_read_byte() - Issue a single byte read TRE on a channel 214 * @gsi: GSI pointer 215 * @channel_id: Channel on which to read a byte 216 * @addr: DMA address into which to transfer the one byte 217 * 218 * This is not a transaction operation at all. It's defined here because 219 * it needs to be done in coordination with other transaction activity. 220 */ 221 int gsi_trans_read_byte(struct gsi *gsi, u32 channel_id, dma_addr_t addr); 222 223 /** 224 * gsi_trans_read_byte_done() - Clean up after a single byte read TRE 225 * @gsi: GSI pointer 226 * @channel_id: Channel on which byte was read 227 * 228 * This function needs to be called to signal that the work related 229 * to reading a byte initiated by gsi_trans_read_byte() is complete. 230 */ 231 void gsi_trans_read_byte_done(struct gsi *gsi, u32 channel_id); 232 233 #endif /* _GSI_TRANS_H_ */ 234