linux/include/linux/dma/sprd-dma.h
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   1/* SPDX-License-Identifier: GPL-2.0 */
   2
   3#ifndef _SPRD_DMA_H_
   4#define _SPRD_DMA_H_
   5
   6#define SPRD_DMA_REQ_SHIFT      8
   7#define SPRD_DMA_TRG_MODE_SHIFT 16
   8#define SPRD_DMA_CHN_MODE_SHIFT 24
   9#define SPRD_DMA_FLAGS(chn_mode, trg_mode, req_mode, int_type) \
  10        ((chn_mode) << SPRD_DMA_CHN_MODE_SHIFT | \
  11        (trg_mode) << SPRD_DMA_TRG_MODE_SHIFT | \
  12        (req_mode) << SPRD_DMA_REQ_SHIFT | (int_type))
  13
  14/*
  15 * The Spreadtrum DMA controller supports channel 2-stage tansfer, that means
  16 * we can request 2 dma channels, one for source channel, and another one for
  17 * destination channel. Each channel is independent, and has its own
  18 * configurations. Once the source channel's transaction is done, it will
  19 * trigger the destination channel's transaction automatically by hardware
  20 * signal.
  21 *
  22 * To support 2-stage tansfer, we must configure the channel mode and trigger
  23 * mode as below definition.
  24 */
  25
  26/*
  27 * enum sprd_dma_chn_mode: define the DMA channel mode for 2-stage transfer
  28 * @SPRD_DMA_CHN_MODE_NONE: No channel mode setting which means channel doesn't
  29 * support the 2-stage transfer.
  30 * @SPRD_DMA_SRC_CHN0: Channel used as source channel 0.
  31 * @SPRD_DMA_SRC_CHN1: Channel used as source channel 1.
  32 * @SPRD_DMA_DST_CHN0: Channel used as destination channel 0.
  33 * @SPRD_DMA_DST_CHN1: Channel used as destination channel 1.
  34 *
  35 * Now the DMA controller can supports 2 groups 2-stage transfer.
  36 */
  37enum sprd_dma_chn_mode {
  38        SPRD_DMA_CHN_MODE_NONE,
  39        SPRD_DMA_SRC_CHN0,
  40        SPRD_DMA_SRC_CHN1,
  41        SPRD_DMA_DST_CHN0,
  42        SPRD_DMA_DST_CHN1,
  43};
  44
  45/*
  46 * enum sprd_dma_trg_mode: define the DMA channel trigger mode for 2-stage
  47 * transfer
  48 * @SPRD_DMA_NO_TRG: No trigger setting.
  49 * @SPRD_DMA_FRAG_DONE_TRG: Trigger the transaction of destination channel
  50 * automatically once the source channel's fragment request is done.
  51 * @SPRD_DMA_BLOCK_DONE_TRG: Trigger the transaction of destination channel
  52 * automatically once the source channel's block request is done.
  53 * @SPRD_DMA_TRANS_DONE_TRG: Trigger the transaction of destination channel
  54 * automatically once the source channel's transfer request is done.
  55 * @SPRD_DMA_LIST_DONE_TRG: Trigger the transaction of destination channel
  56 * automatically once the source channel's link-list request is done.
  57 */
  58enum sprd_dma_trg_mode {
  59        SPRD_DMA_NO_TRG,
  60        SPRD_DMA_FRAG_DONE_TRG,
  61        SPRD_DMA_BLOCK_DONE_TRG,
  62        SPRD_DMA_TRANS_DONE_TRG,
  63        SPRD_DMA_LIST_DONE_TRG,
  64};
  65
  66/*
  67 * enum sprd_dma_req_mode: define the DMA request mode
  68 * @SPRD_DMA_FRAG_REQ: fragment request mode
  69 * @SPRD_DMA_BLK_REQ: block request mode
  70 * @SPRD_DMA_TRANS_REQ: transaction request mode
  71 * @SPRD_DMA_LIST_REQ: link-list request mode
  72 *
  73 * We have 4 types request mode: fragment mode, block mode, transaction mode
  74 * and linklist mode. One transaction can contain several blocks, one block can
  75 * contain several fragments. Link-list mode means we can save several DMA
  76 * configuration into one reserved memory, then DMA can fetch each DMA
  77 * configuration automatically to start transfer.
  78 */
  79enum sprd_dma_req_mode {
  80        SPRD_DMA_FRAG_REQ,
  81        SPRD_DMA_BLK_REQ,
  82        SPRD_DMA_TRANS_REQ,
  83        SPRD_DMA_LIST_REQ,
  84};
  85
  86/*
  87 * enum sprd_dma_int_type: define the DMA interrupt type
  88 * @SPRD_DMA_NO_INT: do not need generate DMA interrupts.
  89 * @SPRD_DMA_FRAG_INT: fragment done interrupt when one fragment request
  90 * is done.
  91 * @SPRD_DMA_BLK_INT: block done interrupt when one block request is done.
  92 * @SPRD_DMA_BLK_FRAG_INT: block and fragment interrupt when one fragment
  93 * or one block request is done.
  94 * @SPRD_DMA_TRANS_INT: tansaction done interrupt when one transaction
  95 * request is done.
  96 * @SPRD_DMA_TRANS_FRAG_INT: transaction and fragment interrupt when one
  97 * transaction request or fragment request is done.
  98 * @SPRD_DMA_TRANS_BLK_INT: transaction and block interrupt when one
  99 * transaction request or block request is done.
 100 * @SPRD_DMA_LIST_INT: link-list done interrupt when one link-list request
 101 * is done.
 102 * @SPRD_DMA_CFGERR_INT: configure error interrupt when configuration is
 103 * incorrect.
 104 */
 105enum sprd_dma_int_type {
 106        SPRD_DMA_NO_INT,
 107        SPRD_DMA_FRAG_INT,
 108        SPRD_DMA_BLK_INT,
 109        SPRD_DMA_BLK_FRAG_INT,
 110        SPRD_DMA_TRANS_INT,
 111        SPRD_DMA_TRANS_FRAG_INT,
 112        SPRD_DMA_TRANS_BLK_INT,
 113        SPRD_DMA_LIST_INT,
 114        SPRD_DMA_CFGERR_INT,
 115};
 116
 117/*
 118 * struct sprd_dma_linklist - DMA link-list address structure
 119 * @virt_addr: link-list virtual address to configure link-list node
 120 * @phy_addr: link-list physical address to link DMA transfer
 121 * @wrap_addr: the wrap address for link-list mode, which means once the
 122 * transfer address reaches the wrap address, the next transfer address
 123 * will jump to the address specified by wrap_to register.
 124 *
 125 * The Spreadtrum DMA controller supports the link-list mode, that means slaves
 126 * can supply several groups configurations (each configuration represents one
 127 * DMA transfer) saved in memory, and DMA controller will link these groups
 128 * configurations by writing the physical address of each configuration into the
 129 * link-list register.
 130 *
 131 * Just as shown below, the link-list pointer register will be pointed to the
 132 * physical address of 'configuration 1', and the 'configuration 1' link-list
 133 * pointer will be pointed to 'configuration 2', and so on.
 134 * Once trigger the DMA transfer, the DMA controller will load 'configuration
 135 * 1' to its registers automatically, after 'configuration 1' transaction is
 136 * done, DMA controller will load 'configuration 2' automatically, until all
 137 * DMA transactions are done.
 138 *
 139 * Note: The last link-list pointer should point to the physical address
 140 * of 'configuration 1', which can avoid DMA controller loads incorrect
 141 * configuration when the last configuration transaction is done.
 142 *
 143 *     DMA controller                    linklist memory
 144 * ======================             -----------------------
 145 *|                      |           |    configuration 1    |<---
 146 *|   DMA controller     |   ------->|                       |   |
 147 *|                      |   |       |                       |   |
 148 *|                      |   |       |                       |   |
 149 *|                      |   |       |                       |   |
 150 *| linklist pointer reg |----   ----|    linklist pointer   |   |
 151 * ======================        |    -----------------------    |
 152 *                               |                               |
 153 *                               |    -----------------------    |
 154 *                               |   |    configuration 2    |   |
 155 *                               --->|                       |   |
 156 *                                   |                       |   |
 157 *                                   |                       |   |
 158 *                                   |                       |   |
 159 *                               ----|    linklist pointer   |   |
 160 *                               |    -----------------------    |
 161 *                               |                               |
 162 *                               |    -----------------------    |
 163 *                               |   |    configuration 3    |   |
 164 *                               --->|                       |   |
 165 *                                   |                       |   |
 166 *                                   |           .           |   |
 167 *                                               .               |
 168 *                                               .               |
 169 *                                               .               |
 170 *                               |               .               |
 171 *                               |    -----------------------    |
 172 *                               |   |    configuration n    |   |
 173 *                               --->|                       |   |
 174 *                                   |                       |   |
 175 *                                   |                       |   |
 176 *                                   |                       |   |
 177 *                                   |    linklist pointer   |----
 178 *                                    -----------------------
 179 *
 180 * To support the link-list mode, DMA slaves should allocate one segment memory
 181 * from always-on IRAM or dma coherent memory to store these groups of DMA
 182 * configuration, and pass the virtual and physical address to DMA controller.
 183 */
 184struct sprd_dma_linklist {
 185        unsigned long virt_addr;
 186        phys_addr_t phy_addr;
 187        phys_addr_t wrap_addr;
 188};
 189
 190#endif
 191