// check temperature of FB-DIMM modules on tyan s2696
// http://lists.lm-sensors.org/pipermail/lm-sensors/2007-January/018655.html
// http://lists.lm-sensors.org/pipermail/lm-sensors/2007-January/018661.html
// g++ -o ~alpha/bin/fbdimm_temp fbdimm_temp.c

#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>

int main(int argc,char* argv)
{
  int fd = open("/dev/mem", O_RDONLY);
  if ( fd == -1 ) {
    perror("failed to open /dev/mem"); return(1);
  }
  unsigned char* addr = (unsigned char*) mmap(0, 128*1024*1024, PROT_READ, MAP_PRIVATE, fd, 0xFE000000);
  if ( addr == MAP_FAILED ) {
    perror("mmap failed"); return(1);
  }
  // we want function 3, 4 channels, 16AMB/channel
  for (int i=0, dimm=0; i < 64; i++ ) {
    char buf[128];
    int idx = i*2048;
    if ( addr[idx] != 0xff || addr[idx+1] != 0xff ) {
      sprintf(buf, "Intel sig at %i: %02x %02x", i, addr[idx], addr[idx+1]);
      // offset 85h function 3
      usleep(1000);	// delay to get correct value
      printf("FB-DIMM %d temp is: %.1f deg C (%s)\n", ++dimm, addr[idx+(256*3)+0x85]/2., buf);
    }
  }
  munmap(addr, 128*1024*1024);
  return(0);
}