I've just implemented the Cyclades-Z interrupt mode support (the board
currently operates in Linux only in polling mode, although the HW supports
both polling and interrupt modes; once this new patch is applied, it'll
support both modes). Everything works fine for kernels 2.2.x, however in
kernels 2.0.x (namely 2.0.37pre12) I have a rather weird problem.
The first time the driver is called, it reads all the info from the PCI
config. registers, including the IRQ:
/* read PCI configuration area */
pcibios_read_config_byte(cyy_bus, cyy_dev_fn,
PCI_INTERRUPT_LINE, &cy_pci_irq);
pcibios_read_config_dword(cyy_bus, cyy_dev_fn,
PCI_BASE_ADDRESS_0,
(unsigned int *) &cy_pci_addr0);
pcibios_read_config_dword(cyy_bus, cyy_dev_fn,
PCI_BASE_ADDRESS_1,
(unsigned int *) &cy_pci_addr1);
(...)
Ok, the problem is the following: the first time the driver is called, it
reads the correct IRQ and the driver registers it and works great. If I
unload the module and reload it, the driver reads IRQ0 (zero) !!!
If I reboot the system, the driver will again see the correct IRQ and it
will work fine, until I unload / reload the module. After that, it won't
be able to allocate the IRQ (because it doesn't see the right one) and,
thus, it won't work.
The most important point here is: IT WORKS FINE UNDER 2.2.x !!!
Some more info:
- After following the module load/unload/reload procedure that causes the
problem, 'lspci -vvv' shows IRQ=0 under 2.0.x, and it shows
IRQ=<right value> under 2.2.x;
Any hints ???
Regards,
Ivan Passos
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