Description
Name
Bits
When set to zero, the start condition is the sync buffer flag must be equal
to the value in bits 31:24. When set to one, the start condition is equal to
or greater than the value in bits 31:24. This is a circular buffer and Greater
is defined as the buffer flag is within 128 counts of the bits 31:24. From
a mathematical perspective, the bits 31:24 are subtracted from the sync
buffer flag value and if the result is less than 128, the start condition is
met.
Greater
1
Sync information is valid in this descriptor.
Valid
2
Must be set to zero by firmware.
Reserved
3
This bit enables synchronized interrupt across DMA channels. When
this bit set, the controller internally considers Increment and Greater
flags to be set, irrespective of their actual value. The controller checks
StartValue against sync buffer flag; if Greater condition is not met, the
controller proceeds straight to sync buffer value update operation and
increments the buffer flag value. If Greater, then condition is met, and
the controller generates an interrupt on that channel and performs an
Increment operation. The descriptor flash command is considered a NOP
and ignored. This bit is valid only when the
Valid
bit is set. Setting of
this bit also means that the
Int
bit in the Commands Flags field is
ignored.
SyncInt
4
Must be set to zero by firmware.
Reserved
15:5
Value to be stored to the sync buffer flag upon the successful completion
of the operation unless the type is set to Increment.
EndValue
23:16
Start value of the sync buffer flag. The value required to start an operation.
StartValue
31:24
NAND Reset Commands
The host software can use channel reset commands to stop a channel from processing the next descriptor
in the descriptor chain. There are two types of reset commands.
Related Information
on page 10-19
Type 0 Reset Commands
The Type 0 reset command resets the selected channel after the descriptor completes the flash operation
and status has been updated for the descriptor. Sync status is updated if the command is received while
waiting for the flash operation to complete. If this command is received while DMA channel is performing
sync update, the channel finishes the sync update before idling.
Altera Corporation
NAND Flash Controller
10-23
NAND Reset Commands
cv_54010
2013.12.30