Figure 16-2: Thread Operating States
Executing
Cache
Miss
Updating
PC
Waiting
for Event
At Barrier
Waiting for
Peripheral
Completing
Faulting
Completing
Faulting
Stopped
C
C
C
C
C
C
C
C
M
Killing
C
C
C
In the above figure, the DMAC permits all of the following:
• Only DMA channel threads can use states shown in blue
• Arcs with no letter designator indicate state transitions for the DMA manager and DMA channel threads,
otherwise use is restricted as follows:
• C—DMA channel threads only
• M—DMA manager thread only
• States within the dotted line can transition to the Faulting completing, Faulting, or Killing
After the DMAC exits from reset, it sets all DMA channel threads to the Stopped state, and DMA manager
thread moves to the Stopped state.
The following sections describe the
Thread Operating
states:
Stopped
The thread has an invalid PC (Program Counter) and it is not fetching instructions. Depending on the thread
type, you can cause the thread to move to the Executing state by all of the following:
• DMA manager thread—Issuing the DMAGO instruction through the slave interface
• DMA channel thread—Programming the DMA manager thread to execute
DMAGO
for a DMA channel
thread in the Stopped state
Altera Corporation
DMA Controller
16-5
Operating States
cv_54016
2013.12.30