Merge tag 'mmc-10-10-2019' of https://gitlab.denx.de/u-boot/custodians/u-boot-mmc
[platform/kernel/u-boot.git] / include / wait_bit.h
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Wait for bit with timeout and ctrlc
4  *
5  * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
6  */
7
8 #ifndef __WAIT_BIT_H
9 #define __WAIT_BIT_H
10
11 #include <common.h>
12 #include <console.h>
13 #include <watchdog.h>
14 #include <linux/errno.h>
15 #include <asm/io.h>
16
17 /**
18  * wait_for_bit_x()     waits for bit set/cleared in register
19  *
20  * Function polls register waiting for specific bit(s) change
21  * (either 0->1 or 1->0). It can fail under two conditions:
22  * - Timeout
23  * - User interaction (CTRL-C)
24  * Function succeeds only if all bits of masked register are set/cleared
25  * (depending on set option).
26  *
27  * @param reg           Register that will be read (using read_x())
28  * @param mask          Bit(s) of register that must be active
29  * @param set           Selects wait condition (bit set or clear)
30  * @param timeout_ms    Timeout (in milliseconds)
31  * @param breakable     Enables CTRL-C interruption
32  * @return              0 on success, -ETIMEDOUT or -EINTR on failure
33  */
34
35 #define BUILD_WAIT_FOR_BIT(sfx, type, read)                             \
36                                                                         \
37 static inline int wait_for_bit_##sfx(const void *reg,                   \
38                                      const type mask,                   \
39                                      const bool set,                    \
40                                      const unsigned int timeout_ms,     \
41                                      const bool breakable)              \
42 {                                                                       \
43         type val;                                                       \
44         unsigned long start = get_timer(0);                             \
45                                                                         \
46         while (1) {                                                     \
47                 val = read(reg);                                        \
48                                                                         \
49                 if (!set)                                               \
50                         val = ~val;                                     \
51                                                                         \
52                 if ((val & mask) == mask)                               \
53                         return 0;                                       \
54                                                                         \
55                 if (get_timer(start) > timeout_ms)                      \
56                         break;                                          \
57                                                                         \
58                 if (breakable && ctrlc()) {                             \
59                         puts("Abort\n");                                \
60                         return -EINTR;                                  \
61                 }                                                       \
62                                                                         \
63                 udelay(1);                                              \
64                 WATCHDOG_RESET();                                       \
65         }                                                               \
66                                                                         \
67         debug("%s: Timeout (reg=%p mask=%x wait_set=%i)\n", __func__,   \
68               reg, mask, set);                                          \
69                                                                         \
70         return -ETIMEDOUT;                                              \
71 }
72
73 BUILD_WAIT_FOR_BIT(8, u8, readb)
74 BUILD_WAIT_FOR_BIT(le16, u16, readw)
75 BUILD_WAIT_FOR_BIT(16, u16, readw)
76 #ifdef readw_be
77 BUILD_WAIT_FOR_BIT(be16, u16, readw_be)
78 #endif
79 BUILD_WAIT_FOR_BIT(le32, u32, readl)
80 BUILD_WAIT_FOR_BIT(32, u32, readl)
81 #ifdef readl_be
82 BUILD_WAIT_FOR_BIT(be32, u32, readl_be)
83 #endif
84
85 #endif