arch/x86/kernel/eisa.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * EISA specific code
   4  */
   5 #include <linux/ioport.h>
   6 #include <linux/eisa.h>
   7 #include <linux/io.h>
   8
   9 #include <xen/xen.h>
  10
  11 static __init int eisa_bus_probe(void)
  12 {
  13         void __iomem *p;
  14
  15         if (xen_pv_domain() && !xen_initial_domain())
  16                 return 0;
  17
  18         p = ioremap(0x0FFFD9, 4);
  19         if (p && readl(p) == 'E' + ('I' << 8) + ('S' << 16) + ('A' << 24))
  20                 EISA_bus = 1;
  21         iounmap(p);
  22         return 0;
  23 }
  24 subsys_initcall(eisa_bus_probe);