I am trying to bringup a PCI device on an EVAL board. When linux kernel comes up the device is detected and its configuration space is accessible. But the function pci_enable_device() fails with the following error

pci 0001:03:00.0: device not available because of BAR 0 [0x000000-0xfffffff] collisions

Due to this the BAR 0 address register value is reset to 0, hence device addresses are also inaccessible.

What does this error indicate and what have i missed which is causing this issue ?
Also, could you pls let me know the flow in which pci function should be invoked, so that i can access the device.

I am using Linux kernel 2.6.32.

Thanks in advance for any help.