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|
/*
* The MIT License (MIT)
*
* Copyright (c) 2019 Ha Thach (tinyusb.org)
*
* 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.
*
* This file is part of the TinyUSB stack.
*/
/* metadata:
manufacturer: Microchip
*/
#include "sam.h"
#include "bsp/board_api.h"
// Suppress warning caused by mcu driver
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wcast-qual"
#endif
#include "hal/include/hal_gpio.h"
#include "hal/include/hal_init.h"
#include "hpl/gclk/hpl_gclk_base.h"
// SAMD21 specific includes
#if defined(__SAMD21E15A__) || defined(__SAMD21E16A__) || defined(__SAMD21E17A__) || defined(__SAMD21E18A__) || \
defined(__SAMD21G15A__) || defined(__SAMD21G16A__) || defined(__SAMD21G17A__) || defined(__SAMD21G18A__) || \
defined(__SAMD21J15A__) || defined(__SAMD21J16A__) || defined(__SAMD21J17A__) || defined(__SAMD21J18A__)
#define SAMD21_FAMILY
#include "hri/hri_nvmctrl_d21.h"
#include "hpl_pm_config.h"
#include "hpl/pm/hpl_pm_base.h"
#endif
// SAML21/22 specific includes
#if defined(__SAML21E15B__) || defined(__SAML21E16B__) || defined(__SAML21E17B__) || defined(__SAML21E18B__) || \
defined(__SAML21G16B__) || defined(__SAML21G17B__) || defined(__SAML21G18B__) || \
defined(__SAML21J16B__) || defined(__SAML21J17B__) || defined(__SAML21J18B__) || \
defined(__SAML22G16A__) || defined(__SAML22G17A__) || defined(__SAML22G18A__) || \
defined(__SAML22J16A__) || defined(__SAML22J17A__) || defined(__SAML22J18A__) || \
defined(__SAML22N16A__) || defined(__SAML22N17A__) || defined(__SAML22N18A__)
#define SAML2X_FAMILY
#include "hpl_mclk_config.h"
#endif
#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif
#include "board.h"
// board_vbus_set is defined in board.h for boards that support it
#if !defined(board_vbus_set)
#define board_vbus_set(rhport, state) do { (void)(rhport); (void)(state); } while(0)
#endif
//--------------------------------------------------------------------+
// MACRO TYPEDEF CONSTANT ENUM DECLARATION
//--------------------------------------------------------------------+
#ifdef SAMD21_FAMILY
/* Referenced GCLKs, should be initialized firstly */
#define _GCLK_INIT_1ST (1u << 0 | 1u << 1)
/* Not referenced GCLKs, initialized last */
#define _GCLK_INIT_LAST (~_GCLK_INIT_1ST)
#endif
#ifdef SAML2X_FAMILY
/* Referenced GCLKs (out of 0~4), should be initialized firstly */
#define _GCLK_INIT_1ST 0x00000000
/* Not referenced GCLKs, initialized last */
#define _GCLK_INIT_LAST 0x0000001F
#endif
//--------------------------------------------------------------------+
// Forward USB interrupt events to TinyUSB IRQ Handler
//--------------------------------------------------------------------+
void USB_Handler(void) {
#if CFG_TUD_ENABLED
tud_int_handler(0);
#endif
#if CFG_TUH_ENABLED && !CFG_TUH_MAX3421
tuh_int_handler(0);
#endif
}
//--------------------------------------------------------------------+
// Implementation
//--------------------------------------------------------------------+
static void uart_init(void);
#if CFG_TUH_ENABLED && CFG_TUH_MAX3421
#define MAX3421_SERCOM TU_XSTRCAT(SERCOM, MAX3421_SERCOM_ID)
static void max3421_init(void);
#endif
void board_init(void) {
#ifdef SAMD21_FAMILY
// Clock init for SAMD21 ( follow hpl_init.c )
hri_nvmctrl_set_CTRLB_RWS_bf(NVMCTRL, 2);
_pm_init();
_sysctrl_init_sources();
#if _GCLK_INIT_1ST
_gclk_init_generators_by_fref(_GCLK_INIT_1ST);
#endif
_sysctrl_init_referenced_generators();
_gclk_init_generators_by_fref(_GCLK_INIT_LAST);
#endif
#ifdef SAML2X_FAMILY
// Clock init for SAML2x ( follow hpl_init.c )
hri_nvmctrl_set_CTRLB_RWS_bf(NVMCTRL, CONF_NVM_WAIT_STATE);
_set_performance_level(2);
_osc32kctrl_init_sources();
_oscctrl_init_sources();
_mclk_init();
#if _GCLK_INIT_1ST
_gclk_init_generators_by_fref(_GCLK_INIT_1ST);
#endif
_oscctrl_init_referenced_generators();
_gclk_init_generators_by_fref(_GCLK_INIT_LAST);
#if (CONF_PORT_EVCTRL_PORT_0 | CONF_PORT_EVCTRL_PORT_1 | CONF_PORT_EVCTRL_PORT_2 | CONF_PORT_EVCTRL_PORT_3)
hri_port_set_EVCTRL_reg(PORT, 0, CONF_PORTA_EVCTRL);
hri_port_set_EVCTRL_reg(PORT, 1, CONF_PORTB_EVCTRL);
#endif
#endif
// Update SystemCoreClock since it is hard coded with asf4 and not correct
// Init 1ms tick timer (samd SystemCoreClock may not correct)
SystemCoreClock = CONF_CPU_FREQUENCY;
#if CFG_TUSB_OS == OPT_OS_NONE
SysTick_Config(CONF_CPU_FREQUENCY / 1000);
#elif CFG_TUSB_OS == OPT_OS_FREERTOS
// Explicitly disable systick to prevent its ISR from running before scheduler start
SysTick->CTRL &= ~1U;
#endif
// Led init
#ifdef LED_PIN
gpio_set_pin_direction(LED_PIN, GPIO_DIRECTION_OUT);
board_led_write(false);
#endif
// Button init
#ifdef BUTTON_PIN
gpio_set_pin_direction(BUTTON_PIN, GPIO_DIRECTION_IN);
gpio_set_pin_pull_mode(BUTTON_PIN, BUTTON_STATE_ACTIVE ? GPIO_PULL_DOWN : GPIO_PULL_UP);
#endif
uart_init();
#if CFG_TUSB_OS == OPT_OS_FREERTOS
// If freeRTOS is used, IRQ priority is limit by max syscall ( smaller is higher )
NVIC_SetPriority(USB_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY);
#endif
/* USB Clock init
* The USB module requires a GCLK_USB of 48 MHz ~ 0.25% clock
* for low speed and full speed operation. */
#ifdef SAMD21_FAMILY
_pm_enable_bus_clock(PM_BUS_APBB, USB);
_pm_enable_bus_clock(PM_BUS_AHB, USB);
_gclk_enable_channel(USB_GCLK_ID, GCLK_CLKCTRL_GEN_GCLK0_Val);
#endif
#ifdef SAML2X_FAMILY
hri_gclk_write_PCHCTRL_reg(GCLK, USB_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK1_Val | GCLK_PCHCTRL_CHEN);
hri_mclk_set_AHBMASK_USB_bit(MCLK);
hri_mclk_set_APBBMASK_USB_bit(MCLK);
#endif
// USB Pin Init
gpio_set_pin_direction(PIN_PA24, GPIO_DIRECTION_OUT);
gpio_set_pin_level(PIN_PA24, false);
gpio_set_pin_pull_mode(PIN_PA24, GPIO_PULL_OFF);
gpio_set_pin_direction(PIN_PA25, GPIO_DIRECTION_OUT);
gpio_set_pin_level(PIN_PA25, false);
gpio_set_pin_pull_mode(PIN_PA25, GPIO_PULL_OFF);
gpio_set_pin_function(PIN_PA24, PINMUX_PA24G_USB_DM);
gpio_set_pin_function(PIN_PA25, PINMUX_PA25G_USB_DP);
#ifdef SAMD21_FAMILY
// Output 500hz PWM on D12 (PA19 - TCC0 WO[3]) so we can validate the GCLK0 clock speed with a Saleae.
_pm_enable_bus_clock(PM_BUS_APBC, TCC0);
TCC0->PER.bit.PER = 48000000 / 1000;
TCC0->CC[3].bit.CC = 48000000 / 2000;
TCC0->CTRLA.bit.ENABLE = true;
gpio_set_pin_function(PIN_PA19, PINMUX_PA19F_TCC0_WO3);
_gclk_enable_channel(TCC0_GCLK_ID, GCLK_CLKCTRL_GEN_GCLK0_Val);
#endif
#if CFG_TUH_ENABLED
#if CFG_TUH_MAX3421
max3421_init();
#else
// VBUS Power
board_vbus_set(0, true);
#endif
#endif
}
//--------------------------------------------------------------------+
// Board porting API
//--------------------------------------------------------------------+
void board_led_write(bool state) {
(void) state;
#ifdef LED_PIN
gpio_set_pin_level(LED_PIN, state ? LED_STATE_ON : (1 - LED_STATE_ON));
#endif
}
uint32_t board_button_read(void) {
#ifdef BUTTON_PIN
return BUTTON_STATE_ACTIVE == gpio_get_pin_level(BUTTON_PIN);
#else
return 0;
#endif
}
#if defined(UART_SERCOM)
#define BOARD_SERCOM2(n) SERCOM ## n
#define BOARD_SERCOM(n) BOARD_SERCOM2(n)
static void uart_init(void)
{
#if UART_SERCOM == 0
#if UART_TX_PIN == 6
gpio_set_pin_function(PIN_PA06, PINMUX_PA06D_SERCOM0_PAD2);
#elif UART_TX_PIN == 10
gpio_set_pin_function(PIN_PA10, PINMUX_PA10C_SERCOM0_PAD2);
#else
#error "UART_TX_PIN not supported"
#endif
#if UART_RX_PIN == 7
gpio_set_pin_function(PIN_PA07, PINMUX_PA07D_SERCOM0_PAD3);
#elif UART_RX_PIN == 11
gpio_set_pin_function(PIN_PA11, PINMUX_PA11C_SERCOM0_PAD3);
#else
#error "UART_RX_PIN not supported"
#endif
#ifdef SAMD21_FAMILY
// setup clock (48MHz)
_pm_enable_bus_clock(PM_BUS_APBC, SERCOM0);
_gclk_enable_channel(SERCOM0_GCLK_ID_CORE, GCLK_CLKCTRL_GEN_GCLK0_Val);
#endif
#ifdef SAML2X_FAMILY
// setup clock (48MHz)
hri_gclk_write_PCHCTRL_reg(GCLK, SERCOM0_GCLK_ID_CORE, GCLK_PCHCTRL_GEN_GCLK1_Val | GCLK_PCHCTRL_CHEN);
hri_mclk_set_APBCMASK_SERCOM0_bit(MCLK);
#endif
SERCOM0->USART.CTRLA.bit.SWRST = 1; /* reset SERCOM & enable config */
while(SERCOM0->USART.SYNCBUSY.bit.SWRST);
SERCOM0->USART.CTRLA.reg = /* CMODE = 0 -> async, SAMPA = 0, FORM = 0 -> USART frame, SMPR = 0 -> arithmetic baud rate */
SERCOM_USART_CTRLA_SAMPR(1) | /* 0 = 16x / arithmetic baud rate, 1 = 16x / fractional baud rate */
// SERCOM_USART_CTRLA_FORM(0) | /* 0 = USART Frame, 2 = LIN Master */
SERCOM_USART_CTRLA_DORD | /* LSB first */
SERCOM_USART_CTRLA_MODE(1) | /* 0 = Asynchronous, 1 = USART with internal clock */
SERCOM_USART_CTRLA_RXPO(3) | /* pad 3 */
SERCOM_USART_CTRLA_TXPO(1); /* pad 2 */
SERCOM0->USART.CTRLB.reg =
SERCOM_USART_CTRLB_TXEN | /* tx enabled */
SERCOM_USART_CTRLB_RXEN; /* rx enabled */
/* 115200 */
SERCOM0->USART.BAUD.reg = SERCOM_USART_BAUD_FRAC_FP(0) | SERCOM_USART_BAUD_FRAC_BAUD(26);
SERCOM0->USART.CTRLA.bit.ENABLE = 1; /* activate SERCOM */
while(SERCOM0->USART.SYNCBUSY.bit.ENABLE); /* wait for SERCOM to be ready */
#endif
}
static inline void uart_send_buffer(uint8_t const *text, size_t len)
{
for (size_t i = 0; i < len; ++i) {
BOARD_SERCOM(UART_SERCOM)->USART.DATA.reg = text[i];
while((BOARD_SERCOM(UART_SERCOM)->USART.INTFLAG.reg & SERCOM_USART_INTFLAG_TXC) == 0);
}
}
static inline void uart_send_str(const char* text)
{
while (*text) {
BOARD_SERCOM(UART_SERCOM)->USART.DATA.reg = *text++;
while((BOARD_SERCOM(UART_SERCOM)->USART.INTFLAG.reg & SERCOM_USART_INTFLAG_TXC) == 0);
}
}
int board_uart_read(uint8_t* buf, int len)
{
(void) buf; (void) len;
return -1;
}
int board_uart_write(void const * buf, int len)
{
if (len < 0) {
uart_send_str(buf);
} else {
uart_send_buffer(buf, len);
}
return len;
}
#else // ! defined(UART_SERCOM)
static void uart_init(void) {
}
int board_uart_read(uint8_t* buf, int len) {
(void) buf;
(void) len;
return -1;
}
int board_uart_write(void const* buf, int len) {
(void) buf;
(void) len;
return -1;
}
#endif
#if CFG_TUSB_OS == OPT_OS_NONE
volatile uint32_t system_ticks = 0;
void SysTick_Handler(void) {
system_ticks++;
}
uint32_t tusb_time_millis_api(void) {
return system_ticks;
}
#endif
//--------------------------------------------------------------------+
//
//--------------------------------------------------------------------+
#if CFG_TUH_ENABLED && defined(CFG_TUH_MAX3421) && CFG_TUH_MAX3421
static void max3421_init(void) {
//------------- SPI Init -------------//
// MAX3421E max SPI clock is 26MHz however SAMD can only work reliably at 12 Mhz
uint32_t const baudrate = 12000000u;
#ifdef SAMD21_FAMILY
// Enable the APB clock for SERCOM
PM->APBCMASK.reg |= 1u << (PM_APBCMASK_SERCOM0_Pos + MAX3421_SERCOM_ID);
// Configure GCLK for SERCOM
GCLK->CLKCTRL.reg = GCLK_CLKCTRL_ID(GCLK_CLKCTRL_ID_SERCOM0_CORE_Val + MAX3421_SERCOM_ID) |
GCLK_CLKCTRL_GEN_GCLK0 | GCLK_CLKCTRL_CLKEN;
while (GCLK->STATUS.bit.SYNCBUSY);
#endif
#ifdef SAML2X_FAMILY
// Enable the APB clock for SERCOM
hri_mclk_set_APBCMASK_reg(MCLK, 1u << (MCLK_APBCMASK_SERCOM0_Pos + MAX3421_SERCOM_ID));
// Configure GCLK for SERCOM
hri_gclk_write_PCHCTRL_reg(GCLK, SERCOM0_GCLK_ID_CORE + MAX3421_SERCOM_ID,
GCLK_PCHCTRL_GEN_GCLK1_Val | GCLK_PCHCTRL_CHEN);
#endif
Sercom* sercom = MAX3421_SERCOM;
// Disable the SPI module
sercom->SPI.CTRLA.bit.ENABLE = 0;
// Reset the SPI module
sercom->SPI.CTRLA.bit.SWRST = 1;
while (sercom->SPI.SYNCBUSY.bit.SWRST);
// Set up SPI in master mode, MSB first, SPI mode 0
sercom->SPI.CTRLA.reg = SERCOM_SPI_CTRLA_DOPO(MAX3421_TX_PAD) | SERCOM_SPI_CTRLA_DIPO(MAX3421_RX_PAD) |
SERCOM_SPI_CTRLA_MODE(3);
sercom->SPI.CTRLB.reg = SERCOM_SPI_CTRLB_CHSIZE(0) | SERCOM_SPI_CTRLB_RXEN;
while (sercom->SPI.SYNCBUSY.bit.CTRLB == 1);
// Set the baud rate
sercom->SPI.BAUD.reg = (uint8_t) (SystemCoreClock / (2 * baudrate) - 1);
// Configure SPI pins
gpio_set_pin_direction(MAX3421_SCK_PIN, GPIO_DIRECTION_OUT);
gpio_set_pin_pull_mode(MAX3421_SCK_PIN, GPIO_PULL_OFF);
gpio_set_pin_function(MAX3421_SCK_PIN, MAX3421_SERCOM_FUNCTION);
gpio_set_pin_direction(MAX3421_MOSI_PIN, GPIO_DIRECTION_OUT);
gpio_set_pin_pull_mode(MAX3421_MOSI_PIN, GPIO_PULL_OFF);
gpio_set_pin_function(MAX3421_MOSI_PIN, MAX3421_SERCOM_FUNCTION);
gpio_set_pin_direction(MAX3421_MISO_PIN, GPIO_DIRECTION_IN);
gpio_set_pin_pull_mode(MAX3421_MISO_PIN, GPIO_PULL_OFF);
gpio_set_pin_function(MAX3421_MISO_PIN, MAX3421_SERCOM_FUNCTION);
// CS pin
gpio_set_pin_direction(MAX3421_CS_PIN, GPIO_DIRECTION_OUT);
gpio_set_pin_level(MAX3421_CS_PIN, 1);
// Enable the SPI module
sercom->SPI.CTRLA.bit.ENABLE = 1;
while (sercom->SPI.SYNCBUSY.bit.ENABLE);
//------------- External Interrupt -------------//
#ifdef SAMD21_FAMILY
// Enable the APB clock for EIC (External Interrupt Controller)
PM->APBAMASK.reg |= PM_APBAMASK_EIC;
// Configure GCLK for EIC
GCLK->CLKCTRL.reg = GCLK_CLKCTRL_ID_EIC | GCLK_CLKCTRL_GEN_GCLK0 | GCLK_CLKCTRL_CLKEN;
while (GCLK->STATUS.bit.SYNCBUSY);
#endif
#ifdef SAML2X_FAMILY
// Enable the APB clock for EIC
hri_mclk_set_APBAMASK_EIC_bit(MCLK);
// Configure GCLK for EIC
hri_gclk_write_PCHCTRL_reg(GCLK, EIC_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK1_Val | GCLK_PCHCTRL_CHEN);
#endif
// Configure interrupt pin as an input with function A (external interrupt)
gpio_set_pin_direction(MAX3421_INTR_PIN, GPIO_DIRECTION_IN);
gpio_set_pin_pull_mode(MAX3421_INTR_PIN, GPIO_PULL_UP);
gpio_set_pin_function(MAX3421_INTR_PIN, 0);
// Disable EIC
EIC->CTRL.bit.ENABLE = 0;
while (EIC->STATUS.bit.SYNCBUSY);
// Configure EIC to trigger on falling edge
uint8_t const sense_shift = MAX3421_INTR_EIC_ID * 4;
EIC->CONFIG[0].reg &= ~(7 << sense_shift);
EIC->CONFIG[0].reg |= 2 << sense_shift;
#if CFG_TUSB_OS == OPT_OS_FREERTOS
// If freeRTOS is used, IRQ priority is limit by max syscall ( smaller is higher )
NVIC_SetPriority(EIC_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY);
#endif
// Enable External Interrupt
EIC->INTENSET.reg = EIC_INTENSET_EXTINT(1 << MAX3421_INTR_EIC_ID);
// Enable EIC
EIC->CTRL.bit.ENABLE = 1;
while (EIC->STATUS.bit.SYNCBUSY);
}
void EIC_Handler(void) {
// Clear the interrupt flag
EIC->INTFLAG.reg = EIC_INTFLAG_EXTINT(1 << MAX3421_INTR_EIC_ID);
// Call the TinyUSB interrupt handler
tuh_int_handler(1, true);
}
// API to enable/disable MAX3421 INTR pin interrupt
void tuh_max3421_int_api(uint8_t rhport, bool enabled) {
(void) rhport;
if (enabled) {
NVIC_EnableIRQ(EIC_IRQn);
} else {
NVIC_DisableIRQ(EIC_IRQn);
}
}
// API to control MAX3421 SPI CS
void tuh_max3421_spi_cs_api(uint8_t rhport, bool active) {
(void) rhport;
gpio_set_pin_level(MAX3421_CS_PIN, active ? 0 : 1);
}
// API to transfer data with MAX3421 SPI
// Either tx_buf or rx_buf can be NULL, which means transfer is write or read only
bool tuh_max3421_spi_xfer_api(uint8_t rhport, uint8_t const* tx_buf, uint8_t* rx_buf, size_t xfer_bytes) {
(void) rhport;
Sercom* sercom = MAX3421_SERCOM;
for (size_t count = 0; count < xfer_bytes; count++) {
// Wait for the transmit buffer to be empty
while (!sercom->SPI.INTFLAG.bit.DRE);
// Write data to be transmitted
uint8_t data = 0x00;
if (tx_buf) {
data = tx_buf[count];
}
sercom->SPI.DATA.reg = (uint32_t) data;
// Wait for the receive buffer to be filled
while (!sercom->SPI.INTFLAG.bit.RXC);
// Read received data
data = (uint8_t) sercom->SPI.DATA.reg;
if (rx_buf) {
rx_buf[count] = data;
}
}
// wait for bus idle and clear flags
while (!(sercom->SPI.INTFLAG.reg & (SERCOM_SPI_INTFLAG_TXC | SERCOM_SPI_INTFLAG_DRE)));
sercom->SPI.INTFLAG.reg = SERCOM_SPI_INTFLAG_TXC | SERCOM_SPI_INTFLAG_DRE;
return true;
}
#endif
// Stub for libc init array (required by SAML21/SAML22)
#ifdef SAML2X_FAMILY
void _init(void);
void _init(void) {
}
#endif
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