diff options
Diffstat (limited to 'nuttx/arch/arm/src/common/up_udelay.c')
-rw-r--r-- | nuttx/arch/arm/src/common/up_udelay.c | 129 |
1 files changed, 0 insertions, 129 deletions
diff --git a/nuttx/arch/arm/src/common/up_udelay.c b/nuttx/arch/arm/src/common/up_udelay.c deleted file mode 100644 index 8fcb93522..000000000 --- a/nuttx/arch/arm/src/common/up_udelay.c +++ /dev/null @@ -1,129 +0,0 @@ -/**************************************************************************** - * arch/arm/src/common/up_udelay.c - * - * Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved. - * Author: Gregory Nutt <gnutt@nuttx.org> - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in - * the documentation and/or other materials provided with the - * distribution. - * 3. Neither the name NuttX nor the names of its contributors may be - * used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS - * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE - * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, - * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, - * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS - * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED - * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN - * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE - * POSSIBILITY OF SUCH DAMAGE. - * - ****************************************************************************/ - -/**************************************************************************** - * Included Files - ****************************************************************************/ - -#include <nuttx/config.h> -#include <sys/types.h> -#include <nuttx/arch.h> - -/**************************************************************************** - * Definitions - ****************************************************************************/ - -#define CONFIG_BOARD_LOOPSPER100USEC ((CONFIG_BOARD_LOOPSPERMSEC+5)/10) -#define CONFIG_BOARD_LOOPSPER10USEC ((CONFIG_BOARD_LOOPSPERMSEC+50)/100) -#define CONFIG_BOARD_LOOPSPERUSEC ((CONFIG_BOARD_LOOPSPERMSEC+500)/1000) - -/**************************************************************************** - * Private Types - ****************************************************************************/ - -/**************************************************************************** - * Private Function Prototypes - ****************************************************************************/ - -/**************************************************************************** - * Private Variables - ****************************************************************************/ - -/**************************************************************************** - * Private Functions - ****************************************************************************/ - -/**************************************************************************** - * Public Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: up_udelay - * - * Description: - * Delay inline for the requested number of microseconds. NOTE: Because - * of all of the setup, several microseconds will be lost before the actual - * timing looop begins. Thus, the delay will always be a few microseconds - * longer than requested. - * - * *** NOT multi-tasking friendly *** - * - * ASSUMPTIONS: - * The setting CONFIG_BOARD_LOOPSPERMSEC has been calibrated - * - ****************************************************************************/ - -void up_udelay(useconds_t microseconds) -{ - volatile int i; - - /* We'll do this a little at a time because we expect that the - * CONFIG_BOARD_LOOPSPERUSEC is very inaccurate during to truncation in - * the divisions of its calculation. We'll use the largest values that - * we can in order to prevent significant error buildup in the loops. - */ - - while (microseconds > 1000) - { - for (i = 0; i < CONFIG_BOARD_LOOPSPERMSEC; i++) - { - } - microseconds -= 1000; - } - - while (microseconds > 100) - { - for (i = 0; i < CONFIG_BOARD_LOOPSPER100USEC; i++) - { - } - microseconds -= 100; - } - - while (microseconds > 10) - { - for (i = 0; i < CONFIG_BOARD_LOOPSPER10USEC; i++) - { - } - microseconds -= 10; - } - - while (microseconds > 0) - { - for (i = 0; i < CONFIG_BOARD_LOOPSPERUSEC; i++) - { - } - microseconds--; - } -} |