1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
|
/* ----------------------------------------------------------------------------
* ATMEL Microcontroller Software Support
* ----------------------------------------------------------------------------
* Copyright (c) 2008, Atmel Corporation
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the disclaimer below.
*
* Atmel's name may not be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
* DISCLAIMED. IN NO EVENT SHALL ATMEL 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.
* ----------------------------------------------------------------------------
*/
//------------------------------------------------------------------------------
/// \unit
///
/// !Purpose
///
/// Provides the low-level initialization function that gets called on chip
/// startup.
///
/// !Usage
///
/// LowLevelInit() is called in #board_cstartup.S#.
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
// Headers
//------------------------------------------------------------------------------
#include "board.h"
#include "board_memories.h"
#include <pmc/pmc.h>
//------------------------------------------------------------------------------
// Internal definitions
//------------------------------------------------------------------------------
/* Settings at 400/133MHz */
#define BOARD_OSCOUNT (AT91C_CKGR_OSCOUNT & (64 << 8))
#define BOARD_CKGR_PLLA (AT91C_CKGR_SRCA | AT91C_CKGR_OUTA_0)
#define BOARD_PLLACOUNT (0x3F << 8)
#define BOARD_MULA (AT91C_CKGR_MULA & (199 << 16))
#define BOARD_DIVA (AT91C_CKGR_DIVA & 3)
#define BOARD_PRESCALER (0x00001300) //400/133MHz
//#define BOARD_PRESCALER (0x00001200) //400/100MHz
//------------------------------------------------------------------------------
// Internal functions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
/// Default spurious interrupt handler. Infinite loop.
//------------------------------------------------------------------------------
void defaultSpuriousHandler( void )
{
while (1);
}
//------------------------------------------------------------------------------
/// Default handler for fast interrupt requests. Infinite loop.
//------------------------------------------------------------------------------
void defaultFiqHandler( void )
{
while (1);
}
//------------------------------------------------------------------------------
/// Default handler for standard interrupt requests. Infinite loop.
//------------------------------------------------------------------------------
void defaultIrqHandler( void )
{
while (1);
}
//------------------------------------------------------------------------------
// Exported functions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
/// Performs the low-level initialization of the chip. Initialisation depends
/// on where the application is executed:
/// - in sdram: it means that sdram has previously been initialized. No further
/// initialization is required.
/// - in sram: PLL shall be initialized in LowLevelInit. Other initializations
/// can be done later by the application.
/// - in norflash: LowLevelInit can't be executed in norflash because SMC
/// settings can't be changed while executing in external flash.
/// LowLevelInit shall be executed in internal sram. It initializes
/// PLL and SMC.
/// This function also reset the AIC and disable RTT and PIT interrupts
//------------------------------------------------------------------------------
void LowLevelInit(void)
{
unsigned char i;
#if !defined(ddram)
/* Initialize main oscillator
****************************/
AT91C_BASE_PMC->PMC_MOR = BOARD_OSCOUNT | AT91C_CKGR_MOSCEN;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MOSCS));
/* Initialize PLLA */
AT91C_BASE_PMC->PMC_PLLAR = BOARD_CKGR_PLLA
| BOARD_PLLACOUNT
| BOARD_MULA
| BOARD_DIVA;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_LOCKA));
/* Wait for the master clock if it was already initialized */
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY));
/* Switch to fast clock
**********************/
/* Switch to main oscillator + prescaler */
AT91C_BASE_PMC->PMC_MCKR = BOARD_PRESCALER;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY));
/* Switch to PLL + prescaler */
AT91C_BASE_PMC->PMC_MCKR |= AT91C_PMC_CSS_PLLA_CLK;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY));
#endif
/* Initialize AIC
****************/
AT91C_BASE_AIC->AIC_IDCR = 0xFFFFFFFF;
AT91C_BASE_AIC->AIC_SVR[0] = (unsigned int) defaultFiqHandler;
for (i = 1; i < 31; i++) {
AT91C_BASE_AIC->AIC_SVR[i] = (unsigned int) defaultIrqHandler;
}
AT91C_BASE_AIC->AIC_SPU = (unsigned int) defaultSpuriousHandler;
// Unstack nested interrupts
for (i = 0; i < 8 ; i++) {
AT91C_BASE_AIC->AIC_EOICR = 0;
}
/* Watchdog initialization
*************************/
#ifndef WDT_APP // Watchdog init in application ?
AT91C_BASE_WDTC->WDTC_WDMR = AT91C_WDTC_WDDIS;
#endif
/* Remap
*******/
BOARD_RemapRam();
// Disable RTT and PIT interrupts (potential problem when program A
// configures RTT, then program B wants to use PIT only, interrupts
// from the RTT will still occur since they both use AT91C_ID_SYS)
AT91C_BASE_RTTC->RTTC_RTMR &= ~(AT91C_RTTC_ALMIEN | AT91C_RTTC_RTTINCIEN);
AT91C_BASE_PITC->PITC_PIMR &= ~AT91C_PITC_PITIEN;
#if defined(norflash)
BOARD_ConfigureNorFlash(BOARD_NORFLASH_DFT_BUS_SIZE);
#endif
}
|
