2 * Copyright © 2012 Keith Packard <keithp@keithp.com>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
26 volatile AO_TICK_TYPE ao_tick_count;
35 volatile __data uint8_t ao_data_interval = 1;
36 volatile __data uint8_t ao_data_count;
39 void stm_systick_isr(void)
41 if (stm_systick.csr & (1 << STM_SYSTICK_CSR_COUNTFLAG)) {
44 if (ao_task_alarm_tick && (int16_t) (ao_tick_count - ao_task_alarm_tick) >= 0)
45 ao_task_check_alarm((uint16_t) ao_tick_count);
48 if (++ao_data_count == ao_data_interval) {
51 #if (AO_DATA_ALL & ~(AO_DATA_ADC))
52 ao_wakeup((void *) &ao_data_count);
61 ao_timer_set_adc_interval(uint8_t interval)
64 ao_data_interval = interval;
70 #define SYSTICK_RELOAD (AO_SYSTICK / 100 - 1)
75 stm_systick.rvr = SYSTICK_RELOAD;
77 stm_systick.csr = ((1 << STM_SYSTICK_CSR_ENABLE) |
78 (1 << STM_SYSTICK_CSR_TICKINT) |
79 (STM_SYSTICK_CSR_CLKSOURCE_HCLK_8 << STM_SYSTICK_CSR_CLKSOURCE));
90 /* Switch to MSI while messing about */
91 stm_rcc.cr |= (1 << STM_RCC_CR_MSION);
92 while (!(stm_rcc.cr & (1 << STM_RCC_CR_MSIRDY)))
95 /* reset SW, HPRE, PPRE1, PPRE2, MCOSEL and MCOPRE */
96 stm_rcc.cfgr &= (uint32_t)0x88FFC00C;
98 /* reset HSION, HSEON, CSSON and PLLON bits */
99 stm_rcc.cr &= 0xeefefffe;
101 /* reset PLLSRC, PLLMUL and PLLDIV bits */
102 stm_rcc.cfgr &= 0xff02ffff;
104 /* Disable all interrupts */
109 stm_rcc.cr |= (1 << STM_RCC_CR_HSEBYP);
111 stm_rcc.cr &= ~(1 << STM_RCC_CR_HSEBYP);
113 /* Enable HSE clock */
114 stm_rcc.cr |= (1 << STM_RCC_CR_HSEON);
115 while (!(stm_rcc.cr & (1 << STM_RCC_CR_HSERDY)))
118 #define STM_RCC_CFGR_SWS_TARGET_CLOCK (STM_RCC_CFGR_SWS_HSE << STM_RCC_CFGR_SWS)
119 #define STM_RCC_CFGR_SW_TARGET_CLOCK (STM_RCC_CFGR_SW_HSE)
120 #define STM_PLLSRC AO_HSE
121 #define STM_RCC_CFGR_PLLSRC_TARGET_CLOCK (1 << STM_RCC_CFGR_PLLSRC)
123 #define STM_HSI 16000000
124 #define STM_RCC_CFGR_SWS_TARGET_CLOCK (STM_RCC_CFGR_SWS_HSI << STM_RCC_CFGR_SWS)
125 #define STM_RCC_CFGR_SW_TARGET_CLOCK (STM_RCC_CFGR_SW_HSI)
126 #define STM_PLLSRC STM_HSI
127 #define STM_RCC_CFGR_PLLSRC_TARGET_CLOCK (0 << STM_RCC_CFGR_PLLSRC)
130 #if !AO_HSE || HAS_ADC
131 /* Enable HSI RC clock 16MHz */
132 stm_rcc.cr |= (1 << STM_RCC_CR_HSION);
133 while (!(stm_rcc.cr & (1 << STM_RCC_CR_HSIRDY)))
137 /* Set flash latency to tolerate 32MHz SYSCLK -> 1 wait state */
139 /* Enable 64-bit access and prefetch */
140 stm_flash.acr |= (1 << STM_FLASH_ACR_ACC64);
141 stm_flash.acr |= (1 << STM_FLASH_ACR_PRFEN);
143 /* Enable 1 wait state so the CPU can run at 32MHz */
144 /* (haven't managed to run the CPU at 32MHz yet, it's at 16MHz) */
145 stm_flash.acr |= (1 << STM_FLASH_ACR_LATENCY);
147 /* Enable power interface clock */
148 stm_rcc.apb1enr |= (1 << STM_RCC_APB1ENR_PWREN);
150 /* Set voltage range to 1.8V */
152 /* poll VOSF bit in PWR_CSR. Wait until it is reset to 0 */
153 while ((stm_pwr.csr & (1 << STM_PWR_CSR_VOSF)) != 0)
156 /* Configure voltage scaling range */
158 cr &= ~(STM_PWR_CR_VOS_MASK << STM_PWR_CR_VOS);
159 cr |= (STM_PWR_CR_VOS_1_8 << STM_PWR_CR_VOS);
162 /* poll VOSF bit in PWR_CSR. Wait until it is reset to 0 */
163 while ((stm_pwr.csr & (1 << STM_PWR_CSR_VOSF)) != 0)
166 /* HCLK to 16MHz -> AHB prescaler = /1 */
168 cfgr &= ~(STM_RCC_CFGR_HPRE_MASK << STM_RCC_CFGR_HPRE);
169 cfgr |= (AO_RCC_CFGR_HPRE_DIV << STM_RCC_CFGR_HPRE);
171 while ((stm_rcc.cfgr & (STM_RCC_CFGR_HPRE_MASK << STM_RCC_CFGR_HPRE)) !=
172 (AO_RCC_CFGR_HPRE_DIV << STM_RCC_CFGR_HPRE))
175 /* APB1 Prescaler = AO_APB1_PRESCALER */
177 cfgr &= ~(STM_RCC_CFGR_PPRE1_MASK << STM_RCC_CFGR_PPRE1);
178 cfgr |= (AO_RCC_CFGR_PPRE1_DIV << STM_RCC_CFGR_PPRE1);
181 /* APB2 Prescaler = AO_APB2_PRESCALER */
183 cfgr &= ~(STM_RCC_CFGR_PPRE2_MASK << STM_RCC_CFGR_PPRE2);
184 cfgr |= (AO_RCC_CFGR_PPRE2_DIV << STM_RCC_CFGR_PPRE2);
187 /* Disable the PLL */
188 stm_rcc.cr &= ~(1 << STM_RCC_CR_PLLON);
189 while (stm_rcc.cr & (1 << STM_RCC_CR_PLLRDY))
192 /* PLLVCO to 96MHz (for USB) -> PLLMUL = 6, PLLDIV = 4 */
194 cfgr &= ~(STM_RCC_CFGR_PLLMUL_MASK << STM_RCC_CFGR_PLLMUL);
195 cfgr &= ~(STM_RCC_CFGR_PLLDIV_MASK << STM_RCC_CFGR_PLLDIV);
197 cfgr |= (AO_RCC_CFGR_PLLMUL << STM_RCC_CFGR_PLLMUL);
198 cfgr |= (AO_RCC_CFGR_PLLDIV << STM_RCC_CFGR_PLLDIV);
201 cfgr &= ~(1 << STM_RCC_CFGR_PLLSRC);
202 cfgr |= STM_RCC_CFGR_PLLSRC_TARGET_CLOCK;
206 /* Enable the PLL and wait for it */
207 stm_rcc.cr |= (1 << STM_RCC_CR_PLLON);
208 while (!(stm_rcc.cr & (1 << STM_RCC_CR_PLLRDY)))
211 /* Switch to the PLL for the system clock */
214 cfgr &= ~(STM_RCC_CFGR_SW_MASK << STM_RCC_CFGR_SW);
215 cfgr |= (STM_RCC_CFGR_SW_PLL << STM_RCC_CFGR_SW);
218 uint32_t c, part, mask, val;
221 mask = (STM_RCC_CFGR_SWS_MASK << STM_RCC_CFGR_SWS);
222 val = (STM_RCC_CFGR_SWS_PLL << STM_RCC_CFGR_SWS);
229 stm_rcc.apb2rstr = 0xffff;
230 stm_rcc.apb1rstr = 0xffff;
231 stm_rcc.ahbrstr = 0x3f;
232 stm_rcc.ahbenr = (1 << STM_RCC_AHBENR_FLITFEN);
236 stm_rcc.apb1rstr = 0;
237 stm_rcc.apb2rstr = 0;
240 /* Clear reset flags */
241 stm_rcc.csr |= (1 << STM_RCC_CSR_RMVF);
245 /* Output SYSCLK on PA8 for measurments */
247 stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOAEN);
249 stm_afr_set(&stm_gpioa, 8, STM_AFR_AF0);
250 stm_moder_set(&stm_gpioa, 8, STM_MODER_ALTERNATE);
251 stm_ospeedr_set(&stm_gpioa, 8, STM_OSPEEDR_40MHz);
253 stm_rcc.cfgr |= (STM_RCC_CFGR_MCOPRE_DIV_1 << STM_RCC_CFGR_MCOPRE);
254 stm_rcc.cfgr |= (STM_RCC_CFGR_MCOSEL_HSE << STM_RCC_CFGR_MCOSEL);