hal_lld.c
4.11 KB
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
/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012 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/>.
---
A special exception to the GPL can be applied should you wish to distribute
a combined work that includes ChibiOS/RT, without being obliged to provide
the source code for any proprietary components. See the file exception.txt
for full details of how and when the exception can be applied.
*/
/**
* @file STM8S/hal_lld.c
* @brief STM8S 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. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Low level HAL driver initialization.
* @details Clock sources initialization, HSI is assumed to be already
* started after reset.
* @note If the @p STM8S_CLOCK_INIT option is set to @p FALSE then the
* initialization is not performed and is left to the application.
*
* @notapi
*/
void hal_lld_init(void) {
#if !STM8S_NO_CLOCK_INIT
/* Makes sure that HSI is stable before proceeding.*/
CLK->ICKR |= CLK_ICKR_HSIEN;
while ((CLK->ICKR & CLK_ICKR_HSIRDY) == 0)
;
/* LSI startup and stabilization if required.*/
#if STM8S_LSI_ENABLED
CLK->ICKR |= CLK_ICKR_LSIEN;
while ((CLK->ICKR & CLK_ICKR_LSIRDY) == 0)
;
#endif
/* HSE startup and stabilization if required.*/
#if STM8S_HSE_ENABLED
CLK->ECKR |= CLK_ECKR_HSEEN;
while ((CLK->ECKR & CLK_ECKR_HSERDY) == 0)
;
#endif
/* Setting up clock dividers.*/
CLK->CKDIVR = (STM8S_HSI_DIVIDER << 3) | (STM8S_CPU_DIVIDER << 0);
/* SYSCLK switch to the selected source, not necessary if it is HSI.*/
#if STM8S_SYSCLK_SOURCE != CLK_SYSSEL_HSI
/* Switching clock (manual switch mode).*/
CLK->SWR = STM8S_SYSCLK_SOURCE;
while ((CLK->SWCR & CLK_SWCR_SWIF) == 0)
;
CLK->SWCR = CLK_SWCR_SWEN;
#endif
/* Clocks initially all disabled.*/
CLK->PCKENR1 = 0;
CLK->PCKENR2 = 0;
/* Other clock related initializations.*/
CLK->CSSR = 0;
CLK->CCOR = 0;
CLK->CANCCR = STM8S_CAN_DIVIDER_VALUE;
/* HSI disabled if it is no more required.*/
#if !STM8S_HSI_ENABLED
CLK->ICKR &= ~CLK_ICKR_HSIEN;
#endif
#endif /* !STM8S_NO_CLOCK_INIT */
}
/** @} */