aboutsummaryrefslogtreecommitdiffstats
path: root/wirish/stm32f2-f4/boards_setup.cpp
blob: aa44a11f59df046a3f09dc74f7361294d31da4f2 (plain)
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
/******************************************************************************
 * The MIT License
 *
 * Copyright (c) 2012 LeafLabs, LLC.
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *****************************************************************************/

/**
 * @file wirish/stm32f2/boards_setup.cpp
 * @author Marti Bolivar <mbolivar@leaflabs.com>
 * @brief STM32F2 chip setup.
 *
 * This file controls how init() behaves on the STM32F2. Be very
 * careful when changing anything here. Many of these values depend
 * upon each other.
 */

#include "boards_private.h"

#include <libmaple/gpio.h>
#include <libmaple/syscfg.h>
#include <libmaple/libmaple_types.h>
#include <wirish/wirish_types.h>
#include <board/board.h>

// Not used by STM32F2
#define FPU_CPACR 0xE000ED88

/* See libmaple/stm32f2-f4/rcc.c for constraints on these values, or the vendor
 * user manual */
#if STM32_MCU_SERIES == STM32_SERIES_F2
    // PLL config for 25 MHz external crystal --> 120 MHz SYSCLK, with
    // 48 MHz PLL48CK.
#   ifndef BOARD_PLL_Q
#   define BOARD_PLL_Q 5
#   endif
#   ifndef BOARD_PLL_P
#   define BOARD_PLL_P 2
#   endif
#   ifndef BOARD_PLL_N
#   define BOARD_PLL_N 240
#   endif
#   ifndef BOARD_PLL_M
#   define BOARD_PLL_M 25
#   endif
#elif STM32_MCU_SERIES == STM32_SERIES_F4
    // PLL config for 8 MHz external crystal --> 84 MHz SYSCLK, with
    // 48 MHz PLL48CK.
#   ifndef BOARD_PLL_Q
#   define BOARD_PLL_Q 7
#   endif
#   ifndef BOARD_PLL_P
#   define BOARD_PLL_P 4
#   endif
#   ifndef BOARD_PLL_N
#   define BOARD_PLL_N 336
#   endif
#   ifndef BOARD_PLL_M
#   define BOARD_PLL_M 8
#   endif
#else
#   error "Unsupported STM32_MCU_SERIES"
#endif

static stm32f2_rcc_pll_data pll_data = {BOARD_PLL_Q,
                                        BOARD_PLL_P,
                                        BOARD_PLL_N,
                                        BOARD_PLL_M};

namespace wirish {
    namespace priv {
        // PLL clocked off of HSE, with above configuration data.
        __weak rcc_pll_cfg w_board_pll_cfg = {RCC_PLLSRC_HSE, &pll_data};

        // Global ADC prescaler
        //
        // On F2, with f_APB2 = 60 MHz, we need f_ADC = f_PCLK2 / 2 to
        // get the (maximum) f_ADC = 30 MHz.
        __weak adc_prescaler w_adc_pre = ADC_PRE_PCLK2_DIV_2;

        // Conservative ADC sample rate. Goal is error less than 1/4
        // LSB with 50 KOhm input impedance.
        //
        // On F2, with f_ADC = 30 MHz, error is acceptable assuming an
        // internal sample and hold capacitance C_ADC at most 8.8 pF
        // (ST doesn't specify the maximum C_ADC, so we had to take a
        // guess). See Equation 1 and Table 61 in the F2 datasheet for
        // more details.
        __weak adc_smp_rate w_adc_smp = ADC_SMPR_144;

        __weak void board_reset_pll(void) {
            // Set PLLCFGR to its reset value.
            RCC_BASE->PLLCFGR = 0x24003010; // FIXME lose the magic number.
        }

        __weak void board_setup_clock_prescalers(void) {
#if STM32_MCU_SERIES == STM32_SERIES_F2
            // On F2, with f_SYSCLK = 120 MHz (as determined by
            // board_pll_cfg),
            //
            // f_AHB  = f_SYSCLK / 1 = 120 MHz
            // f_APB1 = f_AHB / 4    =  30 MHz
            // f_APB2 = f_AHB / 2    =  60 MHz
            rcc_set_prescaler(RCC_PRESCALER_AHB, RCC_AHB_SYSCLK_DIV_1);
            rcc_set_prescaler(RCC_PRESCALER_APB1, RCC_APB1_HCLK_DIV_4);
            rcc_set_prescaler(RCC_PRESCALER_APB2, RCC_APB2_HCLK_DIV_2);
#elif STM32_MCU_SERIES == STM32_SERIES_F4
            // On F2, with f_SYSCLK = 84 MHz (as determined by
            // board_pll_cfg),
            //
            // f_AHB  = f_SYSCLK / 1 = 84 MHz
            // f_APB1 = f_AHB / 2    = 42 MHz
            // f_APB2 = f_AHB / 1    = 84 MHz
            rcc_set_prescaler(RCC_PRESCALER_AHB, RCC_AHB_SYSCLK_DIV_1);
            rcc_set_prescaler(RCC_PRESCALER_APB1, RCC_APB1_HCLK_DIV_2);
            rcc_set_prescaler(RCC_PRESCALER_APB2, RCC_APB2_HCLK_DIV_1);
#else
#   error "Unsupported STM32_MCU_SERIES"
#endif
        }

        __weak void board_setup_gpio(void) {
            gpio_init_all();
        }

        __weak void board_setup_usb(void) {
            // Nothing to do.
        }

        __weak void series_init(void) {
            // We need SYSCFG for external interrupts
            syscfg_init();
            // Turn on the I/O compensation cell, since we drive the
            // GPIOs quickly by default.
            syscfg_enable_io_compensation();

#if STM32_MCU_SERIES == STM32_SERIES_F4
            /* enable fpu with full access */
            *(volatile unsigned int*)FPU_CPACR |= 0xF << 20;
#endif
        }

    }
}