MVME2431: how to use vme?

David De Ridder s970707 at
Wed May 12 01:03:28 EST 1999

On Mon, 10 May 1999, Simone Piccardi wrote:

> I can also load the universe module without problems (at least it gave
> me the message: Universe VME bridge #1 found at bus=0, dev=13 that seems
> OK).


> Now the problem is to test VME (to be precise the real problem is that
> this is my first experience with VME, so have no idea from where to
> start).
> I read the README.universe in the kernel source, and I tried also to use
> the program vmetest.c that I found in the same directory of the kernel
> patches.

> The problem is that that program cannot compile, it start with an error:
> testvme.c:43:  'VME_attr' undeclared ....
> and then gave a lot of other errors. I suppose that this depends on some
> version mismatch (I'm using kernel 2.2.6, with related patch). 

 OK, Gabriel is currently unreachable for two weeks (correct me if
 I'm wrong). So here's some advice to all VME testers : take the
 testvme.c program from Gabriel's website - make sure you have
 a patched 2.2.6 kernel -, strip the program from everything you
 think you don't need. The problem is : use ``window'' instead
 of ``attr''. I think Gabriel was using different (newer? older?)
 include files, because this solves the problem.

 You can start from my own stripped-down version (in attachment).


   David 'Septimus' De Ridder     < at>

"Watching eyes wait for sadness to rise,
 true superstitions combine and thicken
 this poison that reaches my soul,
 this terror that blackens my soul."
 - Anne Clark

-------------- next part --------------
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/vme.h>
#include <errno.h>
#include <sys/mman.h>

#define PATTERN 0x55

#define MBUFSIZE (1<<20)
static char memorymap[MBUFSIZE];

int main(int argc, char *argv[])
	u_char *mp;
  	int fd;
	int error;
	int i, j;
	VME_window memdesc = {base:  0xd00000, 
			      limit: 0xdfffff,
			      flags: VME_AM_A24(16) | VME_USE_MAP | VME_USE_RMW
	VME_atomic_access rmw = {offset: 0,

	/* Open the VME device : */
	fd = open("/dev/vme",O_RDWR);
	if (fd<0) 
		perror("error opening vme"); 

	printf("/dev/vme opened.\n");

	error = ioctl(fd, VME_SET_WINDOW, &memdesc);
	if (error)
	 perror("Failed VME_SET_WINDOW");

	error = ioctl(fd, VME_GET_WINDOW, &memdesc);
	if (error) 
	 perror("Failed VME_GET_WINDOW");

	printf("memdesc: flags %x, vme_addr %x, length %d\n", memdesc.flags,
	       memdesc.base, memdesc.limit-memdesc.base+1);

	if ((u_long)mp == -1) 
	 perror("Mmap failed with");
 	 printf("mem mapped at %p\n", mp);


	return 0;

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