Re: [pci] IO Mapping Trouble

["Jeremy Fillingim" <jfilling@aros.net>]

The size of each image was definitely too large.

 

I made the recommended modifications and everything seems to be working as it should.  I am now able to create several IO space mappings and read and write to them from Linux.  For verification purposes I am communicating with a UART16550 core (from OpenCores) via IO reads and writes.

 

Thank you very much for the help.

 

----- Original Message -----

From: Miha Dolenc

To: pci@opencores.org

Sent: Friday, September 13, 2002 1:17 AM

Subject: Re: [pci] IO Mapping Trouble

Hi!

 

I would guess, that I/O image is too large. As you probably know, PC based computers have separate I/O space, whose size is only 64KB. In CRT application, the minimum image size is 16MB (to save resources).

What you have to do is:

Set PCI_NUM_OF_DEC_ADDR_LINES 20 in pci_user_constants.v.

This will give you a minimum image size of 4KB.

Set PCI_AM2 20'hFFFF_F.

 

This should help.

You also have to be careful about memory mapped images here.

Set PCI_AM0 20'hFFFF_F also.

Set PCI_AM1 to the value, that will represent the size of an image you want.

That would be:

20'hFFFF_F for 4KB

20'hFFFF_E for 8KB

20'hFFFF_C for 16KB

.

.

20'hFFF0_0 for 1MB

20'hFFE0_0 for 2MB

etc..

 

Hope this works!

Let me know, because we haven't been testing I/O accesses in hardware yet!

 

Regards,

Miha Dolenc

----- Original Message -----

From: Jeremy Fillingim

To: pci@opencores.org

Sent: Thursday, September 12, 2002 8:09 PM

Subject: [pci] IO Mapping Trouble

I have been successfully using the OpenCore PCI core in a Spartan-2 200k part.  I have been able to access configuration space directly and through the memory mapped image, I also am able to access a memory mapped image.

 

My only problem comes in when I try to add an additional PCI image that uses an IO mapping, instead of a Memory mapping.

 

I get an error message at boot time saying:

 

PCI I/O Port Conflict: Bus 00, Device 0F, Function 00

 

I press escape to continue booting into Linux.  Once the machine has finished booting, the results of lspci -v are:

 

00:0f.0 Bridge: Unknown device 2321:0001 (rev 01)
 Flags: medium devsel, IRQ 9
 Memory at fe000000 (32-bit, non-prefetchable) [disabled] [size=16M]
 Memory at f7000000 (32-bit, non-prefetchable) [disabled] [size=16M]
 I/O ports at <unassigned> [disabled]

 

When I don't include the IO space image, region 0 and region 1 are fully functional.

 

The changes that I make in pci_user_constants.v over the default crt application version are:

 

`define PCI_IMAGE2

`define PCI_BA2_MEM_IO 1'b1

 

Information and/or suggestions are greatly appreciated.