libethdrivers/src/plat/tx2/uboot/wait_bit.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Wait for bit with timeout and ctrlc
 *
 * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
 */

#pragma once

#include "../unimplemented.h"
#include "../io.h"
#include "tx2_configs.h"

#define ETIMEDOUT       110

/**
 * 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;                           \
    volatile unsigned long count = 0; \
                                    \
    while (count != timeout_ms) {                           \
        val = *((type *)reg);                   \
                                    \
        if (!set)                       \
            val = ~val;                 \
                                    \
        if ((val & mask) == mask)               \
            return 0;                   \
        \
                                    \
        udelay(1000);                       \
        count++; \
    }                               \
                                    \
                                    \
    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