atsam/start/iocopy.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /*
0004  * Copyright (c) 2018 embedded brains GmbH & Co. KG
0005  *
0006  * Redistribution and use in source and binary forms, with or without
0007  * modification, are permitted provided that the following conditions
0008  * are met:
0009  * 1. Redistributions of source code must retain the above copyright
0010  *    notice, this list of conditions and the following disclaimer.
0011  * 2. Redistributions in binary form must reproduce the above copyright
0012  *    notice, this list of conditions and the following disclaimer in the
0013  *    documentation and/or other materials provided with the distribution.
0014  *
0015  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0016  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0017  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0018  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0019  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0020  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0021  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0022  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0023  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0024  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0025  * POSSIBILITY OF SUCH DAMAGE.
0026  */
0027
0028 #include <bsp/iocopy.h>
0029
0030 static void atsam_do_copy(
0031   uint8_t *dst,
0032   const uint8_t *src,
0033   size_t n,
0034   bool aligned
0035 )
0036 {
0037   if (aligned) {
0038     while (n > 3) {
0039       *(uint32_t *)dst = *(uint32_t *)src;
0040       dst += 4;
0041       src += 4;
0042       n -= 4;
0043     }
0044   }
0045
0046   while (n > 0) {
0047     *dst = *src;
0048     ++dst;
0049     ++src;
0050     --n;
0051   }
0052 }
0053
0054 void atsam_copy_to_io(void *dst, const void *src, size_t n)
0055 {
0056   atsam_do_copy(dst, src, n, ((uintptr_t)dst) % 4 == 0);
0057 }
0058
0059 void atsam_copy_from_io(void *dst, const void *src, size_t n)
0060 {
0061   atsam_do_copy(dst, src, n, ((uintptr_t)src) % 4 == 0);
0062 }