ioremap returns NULL
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For each card Iioremap()2 * 16 MB of PCI memory space. It succeeds for the 1st card but for the 2nd card I get NULL as result. This means I cannot use the 2nd card...
I think you are screwed. The ioremap grabs from vmalloc area, which is something like 64MB on i386. The best option is to rewrite the driver to allocate less, and perhaps use fewer modules.
Running a 2G/2G split might help, I'm not sure. But that route has userland implications anyway, so don't.
-- Pete