RS/6000 device driver problem.

[Andre Scheunemann]

Help needed with RS/6000 AIX 3.1 device driver.


I am writing a device driver for a micro-channel card for the RS/6000 with
AIX 3.1.  I'm using the BUSIO_ATT() and BUSMEM_ATT() macros from <sys/adspace.h>
to access the card I/O ports and card memory respectively.  There are no problems
accessing the I/O ports.  However, when I try to access the card memory the system
crashes with a 102 320 led error code.  The following code is used:

{
ulong io_addr, mem_addr;

io_addr = BUSIO_ATT(bus_id, card_io_addr);
mem_addr = BUSMEM_ATT(bus_id, card_mem_addr);

data = BUSIO_GETC(io_addr);	/* this works and causes a read of the I/O register */

data = BUSIO_GETC(mem_addr);	/* this causes a system crash !!!!! */

BUSIO_DET(io_addr);
BUSMEM_DET(mem_addr);
}

The BUSIO_GETC() is a macro from <sys/ioacc.h>.  The same code is used in the sample
device drivers provided in the /usr/lpp/bos/samples directory.

I know that the card memory can be accessed because I can access it using ioctl's on the
/dev/bus0 device.

Can anyone tell me what I'm doing wrong?


Thanks in advance,

andre%eicon at iro.umontreal.ca