1 摘要
使用J6平台开发项目中，使用DMA拷贝数据，针对DMA物理内存和Cache的一致性进行测试和验证。
2 解决方法和目的
方法目的：使用dma_sync_single_for_device();dma_sync_single_for_cpu()对内存进行一致性管理，通过下文的介绍可以正确使用这两个函数。
方法验证：
A. 验证Cache与DMA存在不一致的问题。
B. dma_sync_single_for_device();dma_sync_single_for_cpu()对物理内存和Cache的实际操作内容。
C. 验证函数效率。
2.1 INV和CLEAN概念
（invalidate）清除cache的意思是清除cache中存储的全部数据。对处理器而言，清除操作只要清零相应cache行的有效位即可。当存储器配置上有变化时，整体或部分cache可能需要进行清除操作。
（clean）清理cache的意思是把脏的（即被改写过的）cache行强制写到主存，并把cache行中的脏位清零。清理cache可以重建cache与主存之间的一致性，它只用在使用写回策略的D-cache上。
2.2 测试使用程序列表
| 名称 | 功能 |
| Dmatest | 测试应用程序 |
| omap_ds_dma.ko | 测试对应驱动程序 |
2.3 测试程序命令列表
| 命令名称 | 功能 |
| @cc <n> | Set cache on(1)/off(0)驱动内DMA的cache管理功能 |
| @ccsrc [size] | Make src cached |
| @ccdst [size] | Make dst cached |
| @ccsrcn [size] | Make src cached write 0x66 |
| @ccdstn [size] | Make src cached write 0x33 |
| @up | Update src dynamic val |
| @dmacp | Dma Cp test 0x1000 DMAsrc->dst拷贝4K |
| @dmacp1 | Dma Cp test max DMAsrc->dst拷贝8M |
| @dmacpn <n> | Dma Cp test n times |
| @showm <addr> | Show Mem 0x---- test 显示物理地址内数据 |
| @shows | Show Mem 0xAC000000 |
| @showd | Show Mem 0xAC800000 |
| @coset <val> | Set coherent data 设置Coherent驱动内缓冲区的值 |
| @coshow | Show coherent data显示Coherent驱动内缓冲区的值 |
| @setwb <paddr> | Set write back 设置指定区域的clean功能WB |
| @setinv <paddr> | Set invalide 设置指定区域的invalid功能 |
| @cotocc | Coherent to cache Coherent to dst(cached) DMA拷贝 |
| @cctoco | Cache to Coherent dst(cached) to Coherent 的DMA拷贝 |
| @exit |
|
| @help |
|
2.4 验证条件
a. 驱动程序提供一块一致性内存;
b. 使用物理内存0xAC000000~0xAC800000为src带cache内存。
c. 使用物理内存0xAC800000~0xAD000000为dst带cache内存
2.5 验证1一致性问题存在
使用DMA将no cache数据传送到cached内存，需要将目的内存进行cache，然后启动DMA，再查看目的内存的内容，结果会导致CPU与物理内存不一致
<UT>:coset 0x65
[61901.806422]
[D]Paddr:0xAB859000 Paddr:0xEB859000
[D]coset 0x65
=============BUFF MSG============
[D] 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65
[D] 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65
[D] 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65
[D] 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65
[D]
[D]=============BUFF END============
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E0C000
=============BUFF MSG============
22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
=============BUFF END============
<UT>:cotocc
cotocc
func_get_coherent_arg ioctl paddr 0xab859000, size 0x00001000,
Dma Cp [0xAB859000] -> [0xAC800000] oK,Use time: 1009 us
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E0C000
=============BUFF MSG============
65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65
65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65 65
22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
=============BUFF END============
<UT>:
已验证，会导致数据不一致。
2.6 验证2 invalidate功能清除cache
验证cache invalidate清除功能，使用函数
dma_sync_single_for_cpu(NULL,paddr, size,DMA_FROM_DEVICE);
参数如设置成DMA_TO_DEVICE，该函数什么都不做。
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E0C000
=============BUFF MSG============
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
=============BUFF END============
<UT>:coset 0x43
[62750.244259]
[D]Paddr:0xAB859000 Paddr:0xEB859000
[D]coset 0x43
=============BUFF MSG============
[D] 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43
[D] 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43
[D] 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43
[D] 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43
[D]
[D]=============BUFF END============
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E0C000
=============BUFF MSG============
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
=============BUFF END============
<UT>:cotocc
cotocc
func_get_coherent_arg ioctl paddr 0xab859000, size 0x00001000,
Dma Cp [0xAB859000] -> [0xAC800000] oK,Use time: 1009 us
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E0C000
=============BUFF MSG============
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88 88
=============BUFF END============
<UT>:setinv 0xac800000
[62763.252850]
[62763.252850] [D]Paddr:0xAC800000 Size:0x00001000
setinv 0xac800000
INVALIDE addr is 0xAC800000
func_get_coherent_arg ioctl paddr 0xab859000, size 0x00001000,
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E0C000
=============BUFF MSG============
43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43
43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43
43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43
43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43 43
=============BUFF END============
<UT>:
已验证cache invalidate将cache中的dirty位清除。当再次读取时，会重内存中读取数据。
2.7 验证3 clean清理功能将cache写入内存
验证Clean功能，使用函数
dma_sync_single_for_device(NULL,paddr, size, DMA_TO_DEVICE);
<UT>:showd
showd
pMemDstVirtAddr is 0xB5EA8000
=============BUFF MSG============
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F
20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F
72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F 90 91
92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1
=============BUFF END============
<UT>:ccdstn
ccdstn
<UT>:showd
showd
pMemDstVirtAddr is 0xB5EA8000
=============BUFF MSG============
32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51
52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71
72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F 90 91
92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1
=============BUFF END============
<UT>:showd
showd
pMemDstVirtAddr is 0xB5EA8000
=============BUFF MSG============
32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51
52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71
72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F 90 91
92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1
=============BUFF END============
<UT>:cctoco
cctoco
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
Dma Cp [0xAC800000] -> [0xAB85A000] oK,Use time: 1008 us
<UT>:coshow
[71527.657295]
[D]Paddr:0xAB85A000 Paddr:0xEB85A000
[D]coshow
=============BUFF MSG============
[D] 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F
[D] 20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F
[D] 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F
[D] 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F
[D]
[D]=============BUFF END============
<UT>:setwb 0xac800000
[71532.627374]
[71532.627374] [D]Paddr:0xAC800000 Size:0x00001000
setwb 0xac800000
WRITE_CB addr is 0xAC800000
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
<UT>:cctoco
cctoco
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
Dma Cp [0xAC800000] -> [0xAB85A000] oK,Use time: 1008 us
<UT>:coshow
[71541.280669]
[D]Paddr:0xAB85A000 Paddr:0xEB85A000
[D]coshow
=============BUFF MSG============
[D] 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51
[D] 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71
[D] 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F 90 91
[D] 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1
[D]
[D]=============BUFF END============
2.8 验证4 clean清理功能cache改写才能写入内存
<UT>:showd
showd
pMemDstVirtAddr is 0xB5EA8000
=============BUFF MSG============
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
=============BUFF END============
<UT>:coset 0
[74406.875787]
[D]Paddr:0xAB85A000 Paddr:0xEB85A000
[D]coset 0
=============BUFF MSG============
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D]
[D]=============BUFF END============
<UT>:showd
showd
pMemDstVirtAddr is 0xB5EA8000
=============BUFF MSG============
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
=============BUFF END============
<UT>:cotocc
cotocc
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
Dma Cp [0xAB85A000] -> [0xAC800000] oK,Use time: 1008 us
<UT>:showd
showd
pMemDstVirtAddr is 0xB5EA8000
=============BUFF MSG============
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
=============BUFF END============
<UT>:setwb 0xac800000
[74412.795170]
[74412.795170] [D]Paddr:0xAC800000 Size:0x00001000
setwb 0xac800000
WRITE_CB addr is 0xAC800000
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
<UT>:showd
showd
pMemDstVirtAddr is 0xB5EA8000
=============BUFF MSG============
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63 63
=============BUFF END============
<UT>:cctoco
cctoco
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
Dma Cp [0xAC800000] -> [0xAB85A000] oK,Use time: 1010 us
<UT>:coshow
[74422.187135]
[D]Paddr:0xAB85A000 Paddr:0xEB85A000
[D]coshow
=============BUFF MSG============
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D]
[D]=============BUFF END============
。。。。。。。。。。。
<UT>:showd
showd
pMemDstVirtAddr is 0xB5EA8000
=============BUFF MSG============
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=============BUFF END============
验证到cache的clean功能，在cache未由cpu改写的情况下，并不能把物理内存变化的cache部分进行强制写入。
验证改写部分
<UT>:
<UT>:coset 0
[75962.455990]
[D]Paddr:0xAB85A000 Paddr:0xEB85A000
[D]coset 0
=============BUFF MSG============
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D]
[D]=============BUFF END============
<UT>:dmacp
dmacp
Dma Cp [0xAC000000] -> [0xAC800000] oK,Use time: 1010 us
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E4F000
=============BUFF MSG============
FF 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E
1F 20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E
3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E
5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E
=============BUFF END============
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E4F000
=============BUFF MSG============
FF 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E
1F 20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E
3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E
5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E
=============BUFF END============
<UT>:cotocc
cotocc
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
Dma Cp [0xAB85A000] -> [0xAC800000] oK,Use time: 1007 us
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E4F000
=============BUFF MSG============
FF 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E
1F 20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E
3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E
5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E
=============BUFF END============
<UT>:ccdstn
ccdstn
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E4F000
=============BUFF MSG============
32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51
52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71
72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F 90 91
92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1
=============BUFF END============
<UT>:setwb 0xac800000
[75993.171957]
[75993.171957] [D]Paddr:0xAC800000 Size:0x00001000
setwb 0xac800000
WRITE_CB addr is 0xAC800000
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
<UT>:cctoco
cctoco
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
Dma Cp [0xAC800000] -> [0xAB85A000] oK,Use time: 1009 us
<UT>:coshow
[76001.389677]
[D]Paddr:0xAB85A000 Paddr:0xEB85A000
[D]coshow
=============BUFF MSG============
[D] 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51
[D] 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71
[D] 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F 90 91
[D] 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1
[D]
[D]=============BUFF END============
验证结果
当cache被改写，后执行setwb 0xac800000会强制写入内存。
2.9 验证5 clean清理功能将cache改写后数据相同也有效
[D]coshow
=============BUFF MSG============
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D] 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[D]
[D]=============BUFF END============
<UT>:showd
showd
pMemDstVirtAddr is 0xB5E4F000
=============BUFF MSG============
32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51
52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71
72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F 90 91
92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1
=============BUFF END============
<UT>:ccdstn
ccdstn
<UT>:setwb 0xac800000
[76396.223846]
[76396.223846] [D]Paddr:0xAC800000 Size:0x00001000
setwb 0xac800000
WRITE_CB addr is 0xAC800000
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
<UT>:cctoco
cctoco
func_get_coherent_arg ioctl paddr 0xab85a000, size 0x00001000,
Dma Cp [0xAC800000] -> [0xAB85A000] oK,Use time: 1009 us
<UT>:coshow
[76401.636119]
[D]Paddr:0xAB85A000 Paddr:0xEB85A000
[D]coshow
=============BUFF MSG============
[D] 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51
[D] 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71
[D] 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F 90 91
[D] 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1
[D]
[D]=============BUFF END============
进一步验证得到cache对应的内容只要被再次写入，尽管是相同的数据，Clean也会强制写入内存。
2.10验证效率与flush_cache_all()对比
A. 使用上面函数dma_sync_single_for_cpu和dma_sync_single_for_device测试效率
入口位置Start前使用1次src清理和1次dst清理，DMA 完成使用1次dst清除。
B. flush_cache_all() 两次清理和一次清除所花费的时间
C. 入口位置Start前使用1次all，DMA 完成使用1次all。
3 其他
无。
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