65.14.49 SDMMC AHB Control Register
Name: | SDMMC_ACR |
Offset: | 0x208 |
Reset: | 0x00000000 |
Property: | Read/Write |
Bit | 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | |
Access | |||||||||
Reset |
Bit | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | |
Access | |||||||||
Reset |
Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
DFQOS[3:0] | BUFM[1:0] | ||||||||
Access | R/W | R/W | R/W | R/W | R/W | R/W | |||
Reset | 0 | 0 | 0 | 0 | 0 | 0 |
Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
BMAX[1:0] | |||||||||
Access | R/W | R/W | |||||||
Reset | 0 | 0 |
Bits 15:12 – DFQOS[3:0] Descriptor Fetch QOS
This field defines the QOS value of ADMA AHB access when fetching descriptor. For all other accesses, the QOS is set to 0.
Bits 9:8 – BUFM[1:0] AHB Bufferable Mode
This field defines if last access of data transfer is bufferable or not.
Value | Name | Description |
---|---|---|
0 | NEVER |
All SDMA/ADMA AHB accesses are not bufferable. |
1 | ALWAYS |
All SDMA/ADMA AHB accesses are bufferable. |
2 | BLOCK |
All SDMA/ADMA AHB accesses are bufferable except the last access of a data block. |
3 | TRANSFER |
All SDMA/ADMA AHB accesses are bufferable except the last access of a data transfer. |
Bits 1:0 – BMAX[1:0] AHB Maximum Burst
This field selects the maximum burst size in case of DMA transfer.
Value | Name | Description |
---|---|---|
0 | INCR16 | The maximum burst size is INCR16. |
1 | INCR8 | The maximum burst size is INCR8. |
2 | INCR4 | The maximum burst size is INCR4. |
3 | SINGLE | Only SINGLE transfers are performed. |