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MAP11 Addressing Mapping
Table 10-7: MAP11 Addressing Mapping
Description
Name
Address Bits
Set to 0
(reserved)
31:28
Set to 3
CMD_MAP
27:26
Set to 0
(reserved)
25:2
Sets the control type as follows:
• 0 = Command cycle
• 1 = Address cycle
• 2 = Data Read/Write Cycle
TYPE
1:0
MAP11 Command Usage
Use the MAP11 command as follows:
• Use MAP11 commands only in special cases, for debugging or sending device-specific commands that
are not supported by the NAND flash controller.
• DMA must be disabled before you use MAP11 operations.
• The host can use only single beat access transfers when using MAP11 commands.
MAP11 commands provide direct, unstructured access to the NAND flash device. Incorrect use can
lead to unpredictable behavior.
Note:
Data DMA
The DMA transfers data with minimal host involvement. Software initiates data DMA with the MAP10
command.
The
flag
bit of the
dma_enable
register in the
dma
group enables data DMA functionality. Only enable
or disable this functionality when there are no active transactions pending in the NAND flash controller.
When the DMA is enabled, the flash controller initiates one DMA transfer per MAP10 command over the
DMA master interface. When the DMA is disabled, all operations with the flash controller occur through
the data/command slave interface.
The NAND flash controller supports up to four outstanding DMA commands, and ignores additional DMA
commands. If software issues more than four outstanding DMA commands, the flash controller issues the
unsup_cmd
interrupt. On receipt of a DMA command, the flash controller performs command sequencing
to transfer the number of pages requested in the DMA command. The DMA master reads or writes page
data from the system memory in programmed burst-length chunks. After the DMA command completes,
the flash controller issues an interrupt, and starts working on the next queued DMA command.
Pipelining allows the NAND flash controller to optimize its performance while executing back-to-back
commands of the same type.
With certain restrictions, non-DMA MAP10 commands can be issued to the NAND flash controller while
the flash controller is servicing DMA transactions. MAP00, MAP01, and MAP11 commands cannot be
issued while DMA mode is enabled because the flash controller is operating in an extremely tightly-coupled,
NAND Flash Controller
Altera Corporation
cv_54010
MAP11 Addressing Mapping
10-12
2013.12.30