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

source code of linux/include/linux/dma/sprd-dma.h