circuitpython/ports/stm32f4/supervisor/usb.c

86 lines
3.0 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2018 hathach for Adafruit Industries
*
* 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.
*/
#include "tick.h"
#include "supervisor/usb.h"
#include "lib/utils/interrupt_char.h"
#include "lib/mp-readline/readline.h"
#include "stm32f4xx.h"
void init_usb_hardware(void) {
// Init the LED on PD14
RCC->AHB1ENR |= RCC_AHB1ENR_GPIODEN;
GPIOD->MODER |= GPIO_MODER_MODE14_0;
// USB Clock init
// PLL input- 8 MHz (External oscillator clock; HSI clock tolerance isn't
// tight enough- 1%, need 0.25%)
// VCO input- 1 to 2 MHz (2 MHz, M = 4)
// VCO output- 100 to 432 MHz (144 MHz, N = 72)
// Main PLL out- <= 180 MHz (18 MHz, P = 3- divides by 8)
// USB PLL out- 48 MHz (Q = 3)
RCC->PLLCFGR = RCC_PLLCFGR_PLLSRC_HSE | (3 << RCC_PLLCFGR_PLLQ_Pos) | \
(3 << RCC_PLLCFGR_PLLP_Pos) | (72 << RCC_PLLCFGR_PLLN_Pos) | \
(4 << RCC_PLLCFGR_PLLM_Pos);
// Wait for external clock to become ready
RCC->CR |= RCC_CR_HSEON;
while(!(RCC->CR & RCC_CR_HSERDY_Msk));
// Wait for PLL to become ready
RCC->CR |= RCC_CR_PLLON;
while(!(RCC->CR & RCC_CR_PLLRDY_Msk));
// Switch clocks!
RCC->CFGR |= RCC_CFGR_SW_1;
// Notify runtime of frequency change.
SystemCoreClockUpdate();
#if CFG_TUSB_OS == OPT_OS_NONE
// 1ms tick timer
SysTick_Config(SystemCoreClock / 1000);
#endif
RCC->AHB2ENR |= RCC_AHB2ENR_OTGFSEN;
// USB Pin Init
// PA9- VUSB, PA10- ID, PA11- DM, PA12- DP
// PC0- Power on
RCC->AHB1ENR |= RCC_AHB1ENR_GPIOAEN;
GPIOA->MODER |= GPIO_MODER_MODE9_1 | GPIO_MODER_MODE10_1 | \
GPIO_MODER_MODE11_1 | GPIO_MODER_MODE12_1;
GPIOA->AFR[1] |= (10 << GPIO_AFRH_AFSEL9_Pos) | \
(10 << GPIO_AFRH_AFSEL10_Pos) | (10 << GPIO_AFRH_AFSEL11_Pos) | \
(10 << GPIO_AFRH_AFSEL12_Pos);
// Pullup required on ID, despite the manual claiming there's an
// internal pullup already (page 1245, Rev 17)
GPIOA->PUPDR |= GPIO_PUPDR_PUPD10_0;
}