u-boot/include/wait_bit.h
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

83 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Wait for bit with timeout and ctrlc
*
* (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
*/
#ifndef __WAIT_BIT_H
#define __WAIT_BIT_H
#include <common.h>
#include <console.h>
#include <watchdog.h>
#include <linux/errno.h>
#include <asm/io.h>
/**
* wait_for_bit_x() waits for bit set/cleared in register
*
* Function polls register waiting for specific bit(s) change
* (either 0->1 or 1->0). It can fail under two conditions:
* - Timeout
* - User interaction (CTRL-C)
* Function succeeds only if all bits of masked register are set/cleared
* (depending on set option).
*
* @param reg Register that will be read (using read_x())
* @param mask Bit(s) of register that must be active
* @param set Selects wait condition (bit set or clear)
* @param timeout_ms Timeout (in milliseconds)
* @param breakable Enables CTRL-C interruption
* @return 0 on success, -ETIMEDOUT or -EINTR on failure
*/
#define BUILD_WAIT_FOR_BIT(sfx, type, read) \
\
static inline int wait_for_bit_##sfx(const void *reg, \
const type mask, \
const bool set, \
const unsigned int timeout_ms, \
const bool breakable) \
{ \
type val; \
unsigned long start = get_timer(0); \
\
while (1) { \
val = read(reg); \
\
if (!set) \
val = ~val; \
\
if ((val & mask) == mask) \
return 0; \
\
if (get_timer(start) > timeout_ms) \
break; \
\
if (breakable && ctrlc()) { \
puts("Abort\n"); \
return -EINTR; \
} \
\
udelay(1); \
WATCHDOG_RESET(); \
} \
\
debug("%s: Timeout (reg=%p mask=%x wait_set=%i)\n", __func__, \
reg, mask, set); \
\
return -ETIMEDOUT; \
}
BUILD_WAIT_FOR_BIT(8, u8, readb)
BUILD_WAIT_FOR_BIT(le16, u16, readw)
#ifdef readw_be
BUILD_WAIT_FOR_BIT(be16, u16, readw_be)
#endif
BUILD_WAIT_FOR_BIT(le32, u32, readl)
#ifdef readl_be
BUILD_WAIT_FOR_BIT(be32, u32, readl_be)
#endif
#endif