1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. 4 * Copyright (C) 2019-2022 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 * @gsi: GSI pointer 33 * @channel_id: Channel number transaction is associated with 34 * @cancelled: If set by the core code, transaction was cancelled 35 * @rsvd_count: Number of TREs reserved for this transaction 36 * @used_count: Number of TREs *used* (could be less than rsvd_count) 37 * @len: Number of bytes sent or received by the transaction 38 * @data: Preserved but not touched by the core transaction code 39 * @cmd_opcode: Array of command opcodes (command channel only) 40 * @sgl: An array of scatter/gather entries managed by core code 41 * @direction: DMA transfer direction (DMA_NONE for commands) 42 * @refcount: Reference count used for destruction 43 * @completion: Completed when the transaction completes 44 * @byte_count: TX channel byte count recorded when transaction committed 45 * @trans_count: Channel transaction count when committed (for BQL accounting) 46 * 47 * The @len field is set when the transaction is committed. For RX 48 * transactions it is updated later to reflect the actual number of bytes 49 * received. 50 */ 51 struct gsi_trans { 52 struct gsi *gsi; 53 u8 channel_id; 54 55 bool cancelled; /* true if transaction was cancelled */ 56 57 u8 rsvd_count; /* # TREs requested */ 58 u8 used_count; /* # entries used in sgl[] */ 59 u32 len; /* total # bytes across sgl[] */ 60 61 union { 62 void *data; 63 u8 cmd_opcode[IPA_COMMAND_TRANS_TRE_MAX]; 64 }; 65 struct scatterlist *sgl; 66 enum dma_data_direction direction; 67 68 refcount_t refcount; 69 struct completion completion; 70 71 u64 byte_count; /* channel byte_count when committed */ 72 u64 trans_count; /* channel trans_count when committed */ 73 }; 74 75 /** 76 * gsi_trans_pool_init() - Initialize a pool of structures for transactions 77 * @pool: GSI transaction pool pointer 78 * @size: Size of elements in the pool 79 * @count: Minimum number of elements in the pool 80 * @max_alloc: Maximum number of elements allocated at a time from pool 81 * 82 * Return: 0 if successful, or a negative error code 83 */ 84 int gsi_trans_pool_init(struct gsi_trans_pool *pool, size_t size, u32 count, 85 u32 max_alloc); 86 87 /** 88 * gsi_trans_pool_alloc() - Allocate one or more elements from a pool 89 * @pool: Pool pointer 90 * @count: Number of elements to allocate from the pool 91 * 92 * Return: Virtual address of element(s) allocated from the pool 93 */ 94 void *gsi_trans_pool_alloc(struct gsi_trans_pool *pool, u32 count); 95 96 /** 97 * gsi_trans_pool_exit() - Inverse of gsi_trans_pool_init() 98 * @pool: Pool pointer 99 */ 100 void gsi_trans_pool_exit(struct gsi_trans_pool *pool); 101 102 /** 103 * gsi_trans_pool_init_dma() - Initialize a pool of DMA-able structures 104 * @dev: Device used for DMA 105 * @pool: Pool pointer 106 * @size: Size of elements in the pool 107 * @count: Minimum number of elements in the pool 108 * @max_alloc: Maximum number of elements allocated at a time from pool 109 * 110 * Return: 0 if successful, or a negative error code 111 * 112 * Structures in this pool reside in DMA-coherent memory. 113 */ 114 int gsi_trans_pool_init_dma(struct device *dev, struct gsi_trans_pool *pool, 115 size_t size, u32 count, u32 max_alloc); 116 117 /** 118 * gsi_trans_pool_alloc_dma() - Allocate an element from a DMA pool 119 * @pool: DMA pool pointer 120 * @addr: DMA address "handle" associated with the allocation 121 * 122 * Return: Virtual address of element allocated from the pool 123 * 124 * Only one element at a time may be allocated from a DMA pool. 125 */ 126 void *gsi_trans_pool_alloc_dma(struct gsi_trans_pool *pool, dma_addr_t *addr); 127 128 /** 129 * gsi_trans_pool_exit_dma() - Inverse of gsi_trans_pool_init_dma() 130 * @dev: Device used for DMA 131 * @pool: Pool pointer 132 */ 133 void gsi_trans_pool_exit_dma(struct device *dev, struct gsi_trans_pool *pool); 134 135 /** 136 * gsi_channel_trans_idle() - Return whether no transactions are allocated 137 * @gsi: GSI pointer 138 * @channel_id: Channel the transaction is associated with 139 * 140 * Return: True if no transactions are allocated, false otherwise 141 * 142 */ 143 bool gsi_channel_trans_idle(struct gsi *gsi, u32 channel_id); 144 145 /** 146 * gsi_channel_trans_alloc() - Allocate a GSI transaction on a channel 147 * @gsi: GSI pointer 148 * @channel_id: Channel the transaction is associated with 149 * @tre_count: Number of elements in the transaction 150 * @direction: DMA direction for entire SGL (or DMA_NONE) 151 * 152 * Return: A GSI transaction structure, or a null pointer if all 153 * available transactions are in use 154 */ 155 struct gsi_trans *gsi_channel_trans_alloc(struct gsi *gsi, u32 channel_id, 156 u32 tre_count, 157 enum dma_data_direction direction); 158 159 /** 160 * gsi_trans_free() - Free a previously-allocated GSI transaction 161 * @trans: Transaction to be freed 162 */ 163 void gsi_trans_free(struct gsi_trans *trans); 164 165 /** 166 * gsi_trans_cmd_add() - Add an immediate command to a transaction 167 * @trans: Transaction 168 * @buf: Buffer pointer for command payload 169 * @size: Number of bytes in buffer 170 * @addr: DMA address for payload 171 * @opcode: IPA immediate command opcode 172 */ 173 void gsi_trans_cmd_add(struct gsi_trans *trans, void *buf, u32 size, 174 dma_addr_t addr, enum ipa_cmd_opcode opcode); 175 176 /** 177 * gsi_trans_page_add() - Add a page transfer to a transaction 178 * @trans: Transaction 179 * @page: Page pointer 180 * @size: Number of bytes (starting at offset) to transfer 181 * @offset: Offset within page for start of transfer 182 */ 183 int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size, 184 u32 offset); 185 186 /** 187 * gsi_trans_skb_add() - Add a socket transfer to a transaction 188 * @trans: Transaction 189 * @skb: Socket buffer for transfer (outbound) 190 * 191 * Return: 0, or -EMSGSIZE if socket data won't fit in transaction. 192 */ 193 int gsi_trans_skb_add(struct gsi_trans *trans, struct sk_buff *skb); 194 195 /** 196 * gsi_trans_commit() - Commit a GSI transaction 197 * @trans: Transaction to commit 198 * @ring_db: Whether to tell the hardware about these queued transfers 199 */ 200 void gsi_trans_commit(struct gsi_trans *trans, bool ring_db); 201 202 /** 203 * gsi_trans_commit_wait() - Commit a GSI transaction and wait for it 204 * to complete 205 * @trans: Transaction to commit 206 */ 207 void gsi_trans_commit_wait(struct gsi_trans *trans); 208 209 /** 210 * gsi_trans_read_byte() - Issue a single byte read TRE on a channel 211 * @gsi: GSI pointer 212 * @channel_id: Channel on which to read a byte 213 * @addr: DMA address into which to transfer the one byte 214 * 215 * This is not a transaction operation at all. It's defined here because 216 * it needs to be done in coordination with other transaction activity. 217 */ 218 int gsi_trans_read_byte(struct gsi *gsi, u32 channel_id, dma_addr_t addr); 219 220 /** 221 * gsi_trans_read_byte_done() - Clean up after a single byte read TRE 222 * @gsi: GSI pointer 223 * @channel_id: Channel on which byte was read 224 * 225 * This function needs to be called to signal that the work related 226 * to reading a byte initiated by gsi_trans_read_byte() is complete. 227 */ 228 void gsi_trans_read_byte_done(struct gsi *gsi, u32 channel_id); 229 230 #endif /* _GSI_TRANS_H_ */ 231