1 /**
2  *
3  * \file
4  *
5  * \brief SAM DSU CRC32 driver.
6  *
7  * This file defines a useful set of functions for DSU CRC32 on SAM devices.
8  *
9  * Copyright (c) 2016-2017 Atmel Corporation. All rights reserved.
10  *
11  * \asf_license_start
12  *
13  * \page License
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions are met:
17  *
18  * 1. Redistributions of source code must retain the above copyright notice,
19  *    this list of conditions and the following disclaimer.
20  *
21  * 2. Redistributions in binary form must reproduce the above copyright notice,
22  *    this list of conditions and the following disclaimer in the documentation
23  *    and/or other materials provided with the distribution.
24  *
25  * 3. The name of Atmel may not be used to endorse or promote products derived
26  *    from this software without specific prior written permission.
27  *
28  * 4. This software may only be redistributed and used in connection with an
29  *    Atmel microcontroller product.
30  *
31  * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
32  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
33  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
34  * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
35  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
40  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGE.
42  *
43  * \asf_license_stop
44  *
45  */
46 /*
47  * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
48  */
49 
50 #include <system_interrupt.h>
51 #include <pac.h>
52 #include <crc32.h>
53 
54 /**
55  * \brief Calculate CRC32 value of the input memory
56  *
57  * Calculate CRC32 value of the input memory.
58  *
59  * The read value must be complemented to match standard CRC32 implementations
60  * or kept non-inverted if used as starting point for subsequent CRC32 calculations.
61  *
62  * \param[in] addr    Memory address to calculate CRC32
63  * \param[in] len     Memory length to calculate CRC32
64  * \param[in,out] pcrc32 Initial value used for the CRC32 calculation, and CRC32 result after calculation
65  *
66  * \return Status of the configuration procedure.
67  *
68  * \retval STATUS_OK      If CRC32 calculation OK
69  * \retval STATUS_ERR_BAD_ADDRESS  The address was not aligned with 4 bytes.
70 
71  * \retval STATUS_ERR_IO  A bus error is detected
72  */
dsu_crc32_cal(const uint32_t addr,const uint32_t len,uint32_t * pcrc32)73 enum status_code dsu_crc32_cal(const uint32_t addr, const uint32_t len, uint32_t *pcrc32)
74 {
75 	if (addr & 0x00000003) {
76 		return STATUS_ERR_BAD_ADDRESS;
77 	}
78 
79 	system_interrupt_disable_global();
80 	system_peripheral_unlock(SYSTEM_PERIPHERAL_ID(DSU), ~SYSTEM_PERIPHERAL_ID(DSU));
81 
82 	DSU->DATA.reg = *pcrc32;
83 	DSU->ADDR.reg = addr;
84 	DSU->LENGTH.reg = len;
85 
86 	DSU->CTRL.bit.CRC = 1;
87 	while ((DSU->STATUSA.reg & DSU_STATUSA_DONE) != 1) {
88 	}
89 
90 	if (DSU->STATUSA.reg & DSU_STATUSA_BERR) {
91 		system_peripheral_lock(SYSTEM_PERIPHERAL_ID(DSU), ~SYSTEM_PERIPHERAL_ID(DSU));
92 		system_interrupt_enable_global();
93 		return STATUS_ERR_IO;
94 	}
95 
96 	*pcrc32 = DSU->DATA.reg;
97 	DSU->STATUSA.reg = DSU_STATUSA_DONE;
98 
99 	system_peripheral_lock(SYSTEM_PERIPHERAL_ID(DSU), ~SYSTEM_PERIPHERAL_ID(DSU));
100 	system_interrupt_enable_global();
101 	return STATUS_OK;
102 }