blob: bd021baa4841bd8f132dc19928903da2dbb4c844 [file] [log] [blame]
Mateusz Kulikowski9afdf402016-01-23 11:54:29 +01001/*
2 * Wait for bit with timeout and ctrlc
3 *
4 * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
5 *
6 * SPDX-License-Identifier: GPL-2.0+
7 */
8
9#ifndef __WAIT_BIT_H
10#define __WAIT_BIT_H
11
12#include <common.h>
13#include <console.h>
Michal Simek3cd42182016-12-12 09:46:09 +010014#include <watchdog.h>
Masahiro Yamada1221ce42016-09-21 11:28:55 +090015#include <linux/errno.h>
Mateusz Kulikowski9afdf402016-01-23 11:54:29 +010016#include <asm/io.h>
17
18/**
Álvaro Fernández Rojas91fe4582018-01-23 17:14:54 +010019 * wait_for_bit_x() waits for bit set/cleared in register
20 *
21 * Function polls register waiting for specific bit(s) change
22 * (either 0->1 or 1->0). It can fail under two conditions:
23 * - Timeout
24 * - User interaction (CTRL-C)
25 * Function succeeds only if all bits of masked register are set/cleared
26 * (depending on set option).
27 *
28 * @param reg Register that will be read (using read_x())
29 * @param mask Bit(s) of register that must be active
30 * @param set Selects wait condition (bit set or clear)
31 * @param timeout_ms Timeout (in milliseconds)
32 * @param breakable Enables CTRL-C interruption
33 * @return 0 on success, -ETIMEDOUT or -EINTR on failure
34 */
35
36#define BUILD_WAIT_FOR_BIT(sfx, type, read) \
37 \
38static inline int wait_for_bit_##sfx(const void *reg, \
39 const type mask, \
40 const bool set, \
41 const unsigned int timeout_ms, \
42 const bool breakable) \
43{ \
44 type val; \
45 unsigned long start = get_timer(0); \
46 \
47 while (1) { \
48 val = read(reg); \
49 \
50 if (!set) \
51 val = ~val; \
52 \
53 if ((val & mask) == mask) \
54 return 0; \
55 \
56 if (get_timer(start) > timeout_ms) \
57 break; \
58 \
59 if (breakable && ctrlc()) { \
60 puts("Abort\n"); \
61 return -EINTR; \
62 } \
63 \
64 udelay(1); \
65 WATCHDOG_RESET(); \
66 } \
67 \
68 debug("%s: Timeout (reg=%p mask=%x wait_set=%i)\n", __func__, \
69 reg, mask, set); \
70 \
71 return -ETIMEDOUT; \
72}
73
74BUILD_WAIT_FOR_BIT(8, u8, readb)
75BUILD_WAIT_FOR_BIT(le16, u16, readw)
76#ifdef readw_be
77BUILD_WAIT_FOR_BIT(be16, u16, readw_be)
78#endif
79BUILD_WAIT_FOR_BIT(le32, u32, readl)
80#ifdef readl_be
81BUILD_WAIT_FOR_BIT(be32, u32, readl_be)
82#endif
Mateusz Kulikowski9afdf402016-01-23 11:54:29 +010083
84#endif