LXR uboot/arch/arm/cpu/armv7/syslib.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * (C) Copyright 2008
   4 * Texas Instruments, <www.ti.com>
   5 *
   6 * Richard Woodruff <r-woodruff2@ti.com>
   7 * Syed Mohammed Khasim <khasim@ti.com>
   8 */
   9
  10#include <common.h>
  11#include <asm/io.h>
  12
  13/************************************************************
  14 * sdelay() - simple spin loop.  Will be constant time as
  15 *  its generally used in bypass conditions only.  This
  16 *  is necessary until timers are accessible.
  17 *
  18 *  not inline to increase chances its in cache when called
  19 *************************************************************/
  20void sdelay(unsigned long loops)
  21{
  22        __asm__ volatile ("1:\n" "subs %0, %1, #1\n"
  23                          "bne 1b":"=r" (loops):"0"(loops));
  24}
  25
  26/*********************************************************************
  27 * wait_on_value() - common routine to allow waiting for changes in
  28 *   volatile regs.
  29 *********************************************************************/
  30u32 wait_on_value(u32 read_bit_mask, u32 match_value, void *read_addr,
  31                  u32 bound)
  32{
  33        u32 i = 0, val;
  34        do {
  35                ++i;
  36                val = readl((u32)read_addr) & read_bit_mask;
  37                if (val == match_value)
  38                        return 1;
  39                if (i == bound)
  40                        return 0;
  41        } while (1);
  42}
  43