LXR uboot/include/linux/iopoll.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Copyright (c) 2012-2014 The Linux Foundation. All rights reserved.
   4 */
   5
   6#ifndef _LINUX_IOPOLL_H
   7#define _LINUX_IOPOLL_H
   8
   9#include <linux/delay.h>
  10#include <linux/errno.h>
  11#include <linux/io.h>
  12#include <time.h>
  13
  14/**
  15 * read_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
  16 * @op: accessor function (takes @addr as its only argument)
  17 * @val: Variable to read the value into
  18 * @cond: Break condition (usually involving @val)
  19 * @sleep_us: Maximum time to sleep in us
  20 * @timeout_us: Timeout in us, 0 means never timeout
  21 * @args: arguments for @op poll
  22 *
  23 * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
  24 * case, the last read value at @addr is stored in @val.
  25 *
  26 * When available, you'll probably want to use one of the specialized
  27 * macros defined below rather than this macro directly.
  28 */
  29#define read_poll_timeout(op, val, cond, sleep_us, timeout_us, args...) \
  30({ \
  31        unsigned long timeout = timer_get_us() + timeout_us; \
  32        for (;;) { \
  33                (val) = op(args); \
  34                if (cond) \
  35                        break; \
  36                if (timeout_us && time_after(timer_get_us(), timeout)) { \
  37                        (val) = op(args); \
  38                        break; \
  39                } \
  40                if (sleep_us) \
  41                        udelay(sleep_us); \
  42        } \
  43        (cond) ? 0 : -ETIMEDOUT; \
  44})
  45
  46#define readx_poll_sleep_timeout(op, addr, val, cond, sleep_us, timeout_us) \
  47        read_poll_timeout(op, val, cond, sleep_us, timeout_us, addr)
  48
  49#define readl_poll_sleep_timeout(addr, val, cond, sleep_us, timeout_us) \
  50        readx_poll_sleep_timeout(readl, addr, val, cond, sleep_us, timeout_us)
  51
  52#define readx_poll_timeout(op, addr, val, cond, timeout_us) \
  53        read_poll_timeout(op, val, cond, false, timeout_us, addr)
  54
  55#define readb_poll_timeout(addr, val, cond, timeout_us) \
  56        readx_poll_timeout(readb, addr, val, cond, timeout_us)
  57
  58#define readw_poll_timeout(addr, val, cond, timeout_us) \
  59        readx_poll_timeout(readw, addr, val, cond, timeout_us)
  60
  61#define readl_poll_timeout(addr, val, cond, timeout_us) \
  62        readx_poll_timeout(readl, addr, val, cond, timeout_us)
  63
  64#define readq_poll_timeout(addr, val, cond, timeout_us) \
  65        readx_poll_timeout(readq, addr, val, cond, timeout_us)
  66
  67#define readb_relaxed_poll_timeout(addr, val, cond, timeout_us) \
  68        readx_poll_timeout(readb_relaxed, addr, val, cond, timeout_us)
  69
  70#define readw_relaxed_poll_timeout(addr, val, cond, timeout_us) \
  71        readx_poll_timeout(readw_relaxed, addr, val, cond, timeout_us)
  72
  73#define readl_relaxed_poll_timeout(addr, val, cond, timeout_us) \
  74        readx_poll_timeout(readl_relaxed, addr, val, cond, timeout_us)
  75
  76#define readq_relaxed_poll_timeout(addr, val, cond, timeout_us) \
  77        readx_poll_timeout(readq_relaxed, addr, val, cond, timeout_us)
  78
  79#endif /* _LINUX_IOPOLL_H */
  80