pc-bios/s390-ccw/helper.h

   1 /*
   2  * Helper Functions
   3  *
   4  * Copyright (c) 2019 IBM Corp.
   5  *
   6  * Author(s): Jason J. Herne <jjherne@us.ibm.com>
   7  *
   8  * This work is licensed under the terms of the GNU GPL, version 2 or (at
   9  * your option) any later version. See the COPYING file in the top-level
  10  * directory.
  11  */
  12
  13 #ifndef S390_CCW_HELPER_H
  14 #define S390_CCW_HELPER_H
  15
  16 #include "s390-ccw.h"
  17 #include "s390-time.h"
  18
  19 /* Avoids compiler warnings when casting a pointer to a u32 */
  20 static inline uint32_t ptr2u32(void *ptr)
  21 {
  22     IPL_assert((uint64_t)ptr <= 0xffffffffull, "ptr2u32: ptr too large");
  23     return (uint32_t)(uint64_t)ptr;
  24 }
  25
  26 /* Avoids compiler warnings when casting a u32 to a pointer */
  27 static inline void *u32toptr(uint32_t n)
  28 {
  29     return (void *)(uint64_t)n;
  30 }
  31
  32 static inline void yield(void)
  33 {
  34     asm volatile ("diag %%r0,%%r0,0x44"
  35                   : :
  36                   : "memory", "cc");
  37 }
  38
  39 static inline void sleep(unsigned int seconds)
  40 {
  41     unsigned long target = get_time_seconds() + seconds;
  42
  43     while (get_time_seconds() < target) {
  44         yield();
  45     }
  46 }
  47
  48 #endif