1 /*
2  * Copyright (c) 2006-2021, RT-Thread Development Team
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  *
6  * Change Logs:
7  * Date           Author         Notes
8  * 2020-12-02     bigmagic       first version
9  */
10 #include "drv_dma.h"
11 #include "raspi4.h"
12 #include <rtthread.h>
13 
14 volatile unsigned int __attribute__((aligned(256))) dma_disc[32];
15 //https://www.raspberrypi.org/forums/viewtopic.php?f=72&t=10276
16 static struct rt_semaphore dma_sem;
17 
18 //DMA 0 1 2 3 4 5 6
19 typedef struct _dma_ctrl_block
20 {
21     unsigned int TI;                   // Transfer information
22     unsigned int SOURCE_AD;            // source address
23     unsigned int DEST_AD;              // destination address
24     unsigned int TXFR_LEN;             // transfer length
25     unsigned int STRIDE;               // 2D mode stride
26     struct _dma_ctrl_block *NEXTCONBK; // Next control block address
27     unsigned int DEBUG;
28     unsigned int reserved1;
29 
30 } dma_ctrl_block_t;
31 
32 //DMA 7 8 9 10
33 typedef struct _dma_lite_ctrl_block
34 {
35     unsigned int TI;                        // Transfer information
36     unsigned int SOURCE_AD;                 // source address
37     unsigned int DEST_AD;                   // destination address
38     unsigned int TXFR_LEN;                  // transfer length
39     struct _dma_lite_ctrl_block *NEXTCONBK; // Next control block address
40     unsigned int DEBUG;
41     unsigned int reserved1;
42     unsigned int reserved2;
43 
44 } dma_lite_ctrl_block_t;
45 
46 //DMA 11 12 13 14 15
47 typedef struct _dma4_ctrl_block
48 {
49     unsigned int TI;                    // Transfer information
50     unsigned int SOURCE_AD0;            // source address0
51     unsigned int SOURCE_AD1;            // source address1
52     unsigned int DEST_AD0;              // destination address0
53     unsigned int DEST_AD1;              // destination address1
54     unsigned int TXFR_LEN;              // transfer length
55     unsigned int STRIDE;                // 2D mode stride
56     struct _dma4_ctrl_block *NEXTCONBK; // Next control block address
57 } dma4_ctrl_block_t;
58 
59 static dma_lite_ctrl_block_t *ctr_blocks;
60 
dma_irq(int irq,void * param)61 static void dma_irq(int irq, void *param)
62 {
63     if (DMA_INT_STATUS_REG & DMA_INT7)
64     {
65         DMA_CS(7) = DMA_CS_INT;
66         rt_sem_release(&dma_sem);
67     }
68 }
69 
70 //dma 7 8 9 10:XLENGTH
dma_memcpy(void * src,void * dst,unsigned int size,unsigned int dch,unsigned int timeout)71 rt_err_t dma_memcpy(void *src, void *dst, unsigned int size, unsigned int dch, unsigned int timeout)
72 {
73     rt_hw_cpu_dcache_ops(RT_HW_CACHE_INVALIDATE, dst, size);
74 
75     /* Stop DMA, if it was already started */
76     DMA_CS(dch) = DMA_CS_RESET;
77 
78     /* Clear DMA status flags */
79     DMA_CS(dch) = DMA_CS_INT | DMA_CS_END; /* Interrupted flag & Transmission ended flag*/
80     //cb info
81     ctr_blocks->TI = DMA_TI_SRC_INC | DMA_TI_DEST_INC | DMA_TI_INTEN;
82     ctr_blocks->SOURCE_AD = (unsigned int)src;
83     ctr_blocks->DEST_AD = (unsigned int)dst;
84     ctr_blocks->TXFR_LEN = size;
85     ctr_blocks->NEXTCONBK = 0;
86     ctr_blocks->reserved1 = 0;
87     ctr_blocks->reserved2 = 0;
88 
89     rt_hw_cpu_dcache_ops(RT_HW_CACHE_INVALIDATE, ctr_blocks, sizeof(dma_lite_ctrl_block_t) * 8);
90 
91     DMA_CONBLK_AD(dch) = (rt_uint32_t)ctr_blocks;
92     DMA_CS(dch) = DMA_CS_INT | DMA_CS_END | DMA_CS_ACTIVE;
93 
94     if(rt_sem_take(&dma_sem, timeout) != RT_EOK)
95     {
96         rt_kprintf("dma transfer timeout!\n");
97         return -RT_ERROR;
98     }
99 
100     return RT_EOK;
101 }
102 
dma_init(unsigned char dch)103 void dma_init(unsigned char dch)
104 {
105     rt_sem_init(&dma_sem, "dma_sem", 0, RT_IPC_FLAG_FIFO);
106 
107     ctr_blocks = (dma_lite_ctrl_block_t *)&dma_disc[0]; //rt_malloc(sizeof(DMA_Lite_Control_Block));
108     //Make sure DMA channel is enabled by
109     //writing the corresponding bit in DMA_ENABLE in the DMA register to 1
110     DMA_ENABLE_REG = (1 << dch);
111 
112     rt_hw_interrupt_install(IRQ_DMA7_DMA8, dma_irq, RT_NULL, "dma_irq");
113     rt_hw_interrupt_umask(IRQ_DMA7_DMA8);
114 }
115