> 2. Can the StrongArm initiate a DMA transfer directly between its SDRAM
> and PC host memory? Any idea what is the rough performance is?
Yes. I've only made a couple of measurements:
IXP1200 --> Pentium DMA Push 64-byte block 13.10 MByte/sec
IXP1200 --> Pentium DMA Push 1500-byte block 49.01 MByte/sec
Pentium --> IXP1200 DMA Pull 64-byte block 11.47 MByte/sec
Pentium --> IXP1200 DMA Pull 1500-byte block 24.66 MByte/sec
The performance is dependant on the CPU speed, the chip set, and the
software.
Here are some numbers we measured for a PCI loopback test.
MCE->ARM->IA(IP layer turnaround)->ARM->MCE
(no the code is not available, but it gives you an idea what is possible)
Configuration 64 128 190 256 512
1024 1518
STL2(933Mhz), IXP rev C0, 32/33
frame rate 51,030 47,295 43,217 41,470 33,056 23,622
18,506
PCI Throughput 52,254,720 96,860,160 131,379,680
169,861,120 270,794,752 387,022,848 449,473,728
%gig rate 7 11 15 18 28 39 46
