Samsung S5PC100 User Manual page 962

S5PC100 USER'S MANUAL (REV1.0)
9.2 BLOCK SIZE REGISTER
Host DMA Buffer Boundary and Transfer Block Size Register
•
BLKSIZE0, R/W, Address = 0xED80_0004
•
BLKSIZE1, R/W, Address = 0xED90_0004
•
BLKSIZE2, R/W, Address = 0xEDA0_0004
This register is used to configure the number of bytes in a data block.
BLKSIZE Bit
[15]
BUF [14:12] Host DMA Buffer Boundary
BOUND
Reserved
The large contiguous memory space may not be available in the virtual
memory system. To perform long SDMA transfer, System Address
register is updated at every system memory boundary during SDMA
transfer. These bits specify the size of contiguous buffer in the system
memory. The SDMA transfer waits at the every boundary specified by
these fields and the Host Controller generates the DMA Interrupt to
request the Host Driver to update the SDMA System Address register. At
the end of transfer, the Host Controller issue or not issue DMA Interrupt.
In particular, DMA Interrupt is not issued after Transfer Complete
Interrupt is issued.
If this register is set to 0 (buffer size = 4K bytes), lower 12-bit of byte
address points data in the contiguous buffer and the upper 20-bit points
the location of the buffer in the system memory. The DMA transfer stops if
the Host Controller detects carry out of the address from bit 11 to 12.
These bits are supported if the SDMA Support in the Capabilities register
is set to 1 and this function is active if DMA Enable in the Transfer Mode
register is set to 1.
000b = 4K bytes (Detects A11 carry out)
001b = 8K bytes (Detects A12 carry out)
010b = 16K Bytes (Detects A13 carry out)
011b = 32K Bytes (Detects A14 carry out)
100b = 64K bytes (Detects A15 carry out)
101b = 128K Bytes (Detects A16 carry out)
110b = 256K Bytes (Detects A17 carry out)
111b = 512K Bytes (Detects A18 carry out)
Description
SD/MMC CONTROLLER
Reset Value
0
0
8.12-27