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PCI burst write cycles

dataman
dataman asked
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Hello,

I'm currently developing a device driver to support our custom made PCI board. I can read/write a buffer from/to our PCI device but the system does not use burst write cycles.
Does anyone know how I can use burst write cycles to write from the PC memory to my PCI card. (My PCI card is no busmaster). Do I have to configure something in the PCI bridge ??? I'm using kernel 2.4 (RedHat)

Thanks in advance!
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Commented:
from what I know, dealing with scramnet cards, the burst mode should be already implemented in the firmware, and by You setting a specific register, bit, you should enable this feature which will enable real-time data stuff stuff stuff.
again, what is the question?  Are you actually writing the firmware or the driver for the card?
 If you are writing the driver, then by setting specific bit on card you can recieve all new data with NO work on your part, OS that is.  If you would like to process data At arrivals, then you can use "interrupts"

if you use mmap and create memory mapping it to the pci card mem, data reflects in both.  

did that help or Am I completely OFF-POINT ?

Author

Commented:
Thanks for your comments,
Burst mode must indeed be implemented at chipset level.
But because my device will be used in slave mode (data direction is from the PC to my device) it is not needed to enable burstmode on my slave device. (this would be true if the datadirection was from my device to the PC). The burst mode must be enabled on the master device and because the processor is master, I think I have to set some registers in the PCI bridge to enable burst mode transfer...

Commented:
we do have our wires crossed.
from what I know, which is NOT MUCH :-), you don't need burst mode between your device and PC.  when you map the device memory using mmap, you create a copy of that buffer, and whatever the PC, program change it automatically modified on device buffer.  You can Instantly see the chabges on CARD.
the burst mode is used between several devices, for instance if you have two PCs, each has a device and are connected to each other. Now when PC-1 changes the buffer, the data on PC-1/dev will change, and that is where the burst mode occurs, the PC-1/dev will send an update to the other card PC-2/dev and duplicate the data and visa-versa
THIS IN CASE YOU HAVE A DIRECT CONNECTIVITY BETWEEN THE TWO DEVICES.
now if you are using your OS to update PC-2/dev buffer then it is a horse of a different color, but U use interrupts on data buffer and use, serial or ethernet, to update other cards.

Commented:
dude U still there?
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Commented:
moondancer, U everywhere ain't you?

I don't know what happen to dataman he was doing okay and then Abra-Kadabra poof gone.
You are so right, garboua, it feels like I am everywhere. :)

Sorry you had to wait so long, and thank you for your help here.  I have finalized this today.

Moondancer - EE Moderator