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
|
/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012,2013 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file AT91SAM7/hal_lld.c
* @brief AT91SAM7 HAL subsystem low level driver source.
*
* @addtogroup HAL
* @{
*/
#include "ch.h"
#include "hal.h"
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver interrupt handlers. */
/*===========================================================================*/
static CH_IRQ_HANDLER(spurious_handler) {
CH_IRQ_PROLOGUE();
AT91SAM7_SPURIOUS_HANDLER_HOOK();
AT91C_BASE_AIC->AIC_EOICR = 0;
CH_IRQ_EPILOGUE();
}
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Low level HAL driver initialization.
*
* @notapi
*/
void hal_lld_init(void) {
unsigned i;
/* FIQ Handler weak symbol defined in vectors.s.*/
void FiqHandler(void);
/* Default AIC setup, the device drivers will modify it as needed.*/
AT91C_BASE_AIC->AIC_ICCR = 0xFFFFFFFF;
AT91C_BASE_AIC->AIC_IDCR = 0xFFFFFFFF;
AT91C_BASE_AIC->AIC_SVR[0] = (AT91_REG)FiqHandler;
for (i = 1; i < 31; i++) {
AT91C_BASE_AIC->AIC_SVR[i] = (AT91_REG)NULL;
AT91C_BASE_AIC->AIC_EOICR = (AT91_REG)i;
}
AT91C_BASE_AIC->AIC_SPU = (AT91_REG)spurious_handler;
}
/**
* @brief AT91SAM7 clocks and PLL initialization.
* @note All the involved constants come from the file @p board.h.
* @note This function must be invoked only after the system reset.
*
* @special
*/
void at91sam7_clock_init(void) {
/* wait for reset */
while((AT91C_BASE_RSTC->RSTC_RSR & (AT91C_RSTC_SRCMP | AT91C_RSTC_NRSTL)) != AT91C_RSTC_NRSTL)
;
/* enable reset */
AT91C_BASE_RSTC->RSTC_RMR = ((0xA5 << 24) | AT91C_RSTC_URSTEN);
/* Flash Memory: 1 wait state, about 50 cycles in a microsecond.*/
#if SAM7_PLATFORM == SAM7X512
AT91C_BASE_MC->MC0_FMR = (AT91C_MC_FMCN & (50 << 16)) | AT91C_MC_FWS_1FWS;
AT91C_BASE_MC->MC1_FMR = (AT91C_MC_FMCN & (50 << 16)) | AT91C_MC_FWS_1FWS;
#else
AT91C_BASE_MC->MC_FMR = (AT91C_MC_FMCN & (50 << 16)) | AT91C_MC_FWS_1FWS;
#endif
/* Enables the main oscillator and waits 56 slow cycles as startup time.*/
AT91C_BASE_PMC->PMC_MOR = (AT91C_CKGR_OSCOUNT & (7 << 8)) | AT91C_CKGR_MOSCEN;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MOSCS))
;
/* PLL setup: DIV = 14, MUL = 72, PLLCOUNT = 10
PLLfreq = 96109714 Hz (rounded).*/
AT91C_BASE_PMC->PMC_PLLR = (AT91C_CKGR_DIV & 14) |
(AT91C_CKGR_PLLCOUNT & (10 << 8)) |
(AT91SAM7_USBDIV) |
(AT91C_CKGR_MUL & (72 << 16));
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_LOCK))
;
/* Master clock = PLLfreq / 2 = 48054858 Hz (rounded).*/
AT91C_BASE_PMC->PMC_MCKR = AT91C_PMC_PRES_CLK_2;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY))
;
AT91C_BASE_PMC->PMC_MCKR |= AT91C_PMC_CSS_PLL_CLK;
while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY))
;
}
/** @} */
|
