UM_S3C2501X Datasheet, PDF (356/465 Pages) Samsung semiconductor – 32-BIT RISC MICROPROCESSOR

S3C2501X
GDMA CONTROLLER
The following is the problem solving with software.
1. Method 1
DPRIR
0
0
0
0
0
0
Channel
Expected
Real
Bus
System Bus
Occupancy Occupancy
GDMA 0
1/3
4/6
GDMA 1
1/3
1/6
GDMA 2
1/3
1/6
⇒
0
0
0
0
0
0
Problem
DPRIR
Channel Occupancy
0
GDMA 0
1/3
3
GDMA 1
1/3
3
GDMA 2
1/3
0
0
0
0
0
0
Problem Solving by Method 1
Writing "0x000330", instead of "0x0" will give each channel of three GDMA with the same amount of bus
occupancy.
2. Method 2
DPRIR
0
0
0
0
0
0
Channel
Expected
Real
Bus
System Bus
Occupancy Occupancy
GDMA 0
1/3
4/6
GDMA 1
1/3
1/6
GDMA 2
1/3
1/6
⇒
0
0
0
0
0
0
Problem
DPRIR
Channel Occupancy
0
GDMA 0
1/3
0
0
0
GDMA 2
1/3
0
0
0
GDMA 4
1/3
0
0
Problem Solving by Method 2
With leaving DPRIR as "0x0" and using every other channel, each channel of three GDMA gets the same bus
occupancy, as seen above.
9-7