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Altera_Forum
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20 years ago

PCI in uClinux

Does suported PCI in uClinux for NIOS II with Altera PCI Compiler 4.0 pci_mt_32 megafuntion ? Anywho uses this options ? I can't compile kernel with PCI support... http://forum.nio...
Altera_Forum's avatar
Altera_Forum
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19 years ago

I Have found out another funny thing.

The Altera PCI Bridge has PCI-Bus Access at 0x060000000.

On Page 4 from Setup Offset 0x0000000 is Config, 0x00100000 is Mem and so on.

So, when the System accesses the PCI-Bus it writes a 0x86100000 for Mem in the PCI-Bar, but the physical Bus Access is to Address 0x100000. So the PCI-Device doesn't answer. It's not the same address. I have patched the Linux kernel to mask out the highest bit. And i have told the PCI-Bridge-Setup to map the Mem to 0x061000000.

Now the access is ok. I can read the Config-Register with Memory Access.

But when the Ethernet-Driover wants to access the device it doesn't work.

Please see here a Memory Access Trace: mem_trace (http://www.mabcom.de/memtrace1.jpg)

As you see, the DEVSEL goies Low, also the TRDY, but why so late? Does the Master abort the transfer?

And why are there hundreds off accesses to the same Address?

Thanx

Marco