1 /* 2 * include/asm-s390/io.h 3 * 4 * S390 version 5 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation 6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) 7 * 8 * Derived from "include/asm-i386/io.h" 9 */ 10 11 #ifndef _S390_IO_H 12 #define _S390_IO_H 13 14 #ifdef __KERNEL__ 15 16 #include <asm/page.h> 17 18 #define IO_SPACE_LIMIT 0xffffffff 19 20 /* 21 * Change virtual addresses to physical addresses and vv. 22 * These are pretty trivial 23 */ 24 static inline unsigned long virt_to_phys(volatile void * address) 25 { 26 unsigned long real_address; 27 asm volatile( 28 " lra %0,0(%1)\n" 29 " jz 0f\n" 30 " la %0,0\n" 31 "0:" 32 : "=a" (real_address) : "a" (address) : "cc"); 33 return real_address; 34 } 35 36 static inline void * phys_to_virt(unsigned long address) 37 { 38 return (void *) address; 39 } 40 41 /* 42 * Convert a physical pointer to a virtual kernel pointer for /dev/mem 43 * access 44 */ 45 #define xlate_dev_mem_ptr(p) __va(p) 46 47 /* 48 * Convert a virtual cached pointer to an uncached pointer 49 */ 50 #define xlate_dev_kmem_ptr(p) p 51 52 #endif /* __KERNEL__ */ 53 54 #endif 55