Texas Instruments OMAP5910 Reference Manual page 138

DSP DMA
7.2.8.1 Start Address in DSP Subsystem Data Memory
7.2.8.2 Start Address in I/O Space
138 DSP Subsystem
Figure 65 is a high-level memory map for the DSP subsystem. The diagram
shows both the word addresses (23-bit addresses) used by the DSP core and
byte addresses (24-bit addresses) used by the DMA controller. To load the
source/destination start address registers:
1) Identify the correct start address. Check for any alignment constraint for
the data type; see the description for the DATATYPE bits of DMACSDP
(section 7.3.7). If you have a word address, shift it left by 1 bit to form a byte
address with 24 bits. For example, word address 02 4000h should be
converted to byte address 04 8000h.
2) Load the 16 least significant bits (LSBs) of the byte address into
DMACSSAL (for source) or DMACDSAL (for destination).
3) Load the 8 most significant bits (MSBs) of the byte address into the 8 LSBs
of DMACSSAU (for source) or DMACDSAU (for destination).
Note:
Word addresses 00 0000h-00 005Fh (which correspond to byte addresses
(00 0000h-00 00BFh) are reserved for the memory-mapped registers
(MMRs) of the DSP core.
Figure 66 is an I/O space map for the DSP subsystem. The diagram shows
both the word addresses (16-bit addresses) used by the DSP core and byte
addresses (17-bit addresses) used by the DMA controller. To load the
source/destination start address registers:
1) Identify the correct start address. Check for any alignment constraint for
the data type; see the description for the DATATYPE bits of DMACSDP
(section 7.3.7). If you have a word address, shift it left by 1 bit to form a byte
address with 17 bits. For example, word address 8000h should be
converted to byte address 1 0000h.
2) Load the 16 least significant bits (LSBs) of the byte address into
DMACSSAL (for source) or DMACDSAL (for destination).
3) Load the most significant bit (MSB) of the byte address into the LSB of
DMACSSAU (for source) or DMACDSAU (for destination).
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