text: /* SPDX-License-Identifier: GPL-2.0 */
  #ifndef _LINUX_DELAY_H
  #define _LINUX_DELAY_H
  
  /*
   * Copyright (C) 1993 Linus Torvalds
   *
   * Delay routines, using a pre-computed "loops_per_jiffy" value.
   *
   * Please note that ndelay(), udelay() and mdelay() may return early for
   * several reasons:
   *  1. computed loops_per_jiffy too low (due to the time taken to
   *     execute the timer interrupt.)
   *  2. cache behaviour affecting the time it takes to execute the
   *     loop function.
   *  3. CPU clock rate changes.
   *
   * Please see this thread:
   *   http://lists.openwall.net/linux-kernel/2011/01/09/56
   */
  
  #include <linux/kernel.h>
  
  extern unsigned long loops_per_jiffy;
  
  #include <asm/delay.h>
  
  /*
   * Using udelay() for intervals greater than a few milliseconds can
   * risk overflow for high loops_per_jiffy (high bogomips) machines. The
   * mdelay() provides a wrapper to prevent this.  For delays greater
   * than MAX_UDELAY_MS milliseconds, the wrapper is used.  Architecture
   * specific values can be defined in asm-???/delay.h as an override.
   * The 2nd mdelay() definition ensures GCC will optimize away the 
   * while loop for the common cases where n <= MAX_UDELAY_MS  --  Paul G.
   */
  
  #ifndef MAX_UDELAY_MS
  #define MAX_UDELAY_MS	5
  #endif
  
  #ifndef mdelay
  #define mdelay(n) (\
  	(__builtin_constant_p(n) && (n)<=MAX_UDELAY_MS) ? udelay((n)*1000) : \
  	({unsigned long __ms=(n); while (__ms--) udelay(1000);}))
  #endif
  
  #ifndef ndelay
  static inline void ndelay(unsigned long x)
  {
  	udelay(DIV_ROUND_UP(x, 1000));
  }
  #define ndelay(x) ndelay(x)
  #endif
  
  extern unsigned long lpj_fine;
  void calibrate_delay(void);
  void msleep(unsigned int msecs);
  unsigned long msleep_interruptible(unsigned int msecs);
  void usleep_range(unsigned long min, unsigned long max);
  
  static inline void ssleep(unsigned int seconds)
  {
  	msleep(seconds * 1000);
  }
  
  #endif /* defined(_LINUX_DELAY_H) */
  