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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_gpio.h"
#include "hal_init.h"
#include "hpl/gclk/hpl_gclk_base.h"
#include "hpl_mclk_config.h"
#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif
static inline void board_vbus_set(uint8_t rhport, bool state) TU_ATTR_UNUSED;
#include "board.h"
//--------------------------------------------------------------------+
// MACRO TYPEDEF CONSTANT ENUM DECLARATION
//--------------------------------------------------------------------+
/* Referenced GCLKs, should be initialized firstly */
#define _GCLK_INIT_1ST 0xFFFFFFFF
/* Not referenced GCLKs, initialized last */
#define _GCLK_INIT_LAST (~_GCLK_INIT_1ST)
//--------------------------------------------------------------------+
// Forward USB interrupt events to TinyUSB IRQ Handler
//--------------------------------------------------------------------+
TU_ATTR_ALWAYS_INLINE static inline void USB_Any_Handler(void) {
#if CFG_TUD_ENABLED
tud_int_handler(0);
#endif
#if CFG_TUH_ENABLED && !CFG_TUH_MAX3421
tuh_int_handler(0);
#endif
}
void USB_0_Handler(void) { USB_Any_Handler(); }
void USB_1_Handler(void) { USB_Any_Handler(); }
void USB_2_Handler(void) { USB_Any_Handler(); }
void USB_3_Handler(void) { USB_Any_Handler(); }
//--------------------------------------------------------------------+
// Implementation
//--------------------------------------------------------------------+
#if CFG_TUH_ENABLED && CFG_TUH_MAX3421
#define MAX3421_SERCOM TU_XSTRCAT(SERCOM, MAX3421_SERCOM_ID)
#define MAX3421_EIC_Handler TU_XSTRCAT3(EIC_, MAX3421_INTR_EIC_ID, _Handler)
static void max3421_init(void);
#endif
#if defined(TRACE_ETM)
// same54_xplained routes 4-bit trace to its 20-pin Cortex Debug+ETM header:
// TRACECLK=PC27, D0=PC28, D1=PC26, D2=PC25, D3=PC24 - all peripheral
// function H (CM4 trace). TPIU/ETM are ROM-table-discoverable; the debugger
// arms them, firmware only muxes the pins.
static void trace_etm_init(void) {
// the CM4 trace unit runs from its own GCLK channel (47): feed it GCLK0
// (CPU clock) - without this the pins mux fine but the port stays silent
GCLK->PCHCTRL[47].reg = GCLK_PCHCTRL_GEN_GCLK0 | GCLK_PCHCTRL_CHEN;
while (!(GCLK->PCHCTRL[47].reg & GCLK_PCHCTRL_CHEN)) {}
const uint8_t pin[] = {24, 25, 26, 27, 28};
for (unsigned i = 0; i < 5; i++) {
PORT->Group[2].PINCFG[pin[i]].reg = PORT_PINCFG_PMUXEN | PORT_PINCFG_DRVSTR;
if (pin[i] & 1) {
PORT->Group[2].PMUX[pin[i] >> 1].bit.PMUXO = 7; // function H
} else {
PORT->Group[2].PMUX[pin[i] >> 1].bit.PMUXE = 7;
}
}
}
#else
#define trace_etm_init()
#endif
void board_init(void) {
// Clock init ( follow hpl_init.c )
hri_nvmctrl_set_CTRLA_RWS_bf(NVMCTRL, 0);
_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);
// 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;
trace_etm_init();
#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
gpio_set_pin_direction(LED_PIN, GPIO_DIRECTION_OUT);
gpio_set_pin_level(LED_PIN, 0);
#ifdef BUTTON_PIN
// Button init
gpio_set_pin_direction(BUTTON_PIN, GPIO_DIRECTION_IN);
gpio_set_pin_pull_mode(BUTTON_PIN, GPIO_PULL_UP);
#endif
#if CFG_TUSB_OS == OPT_OS_FREERTOS
// If freeRTOS is used, IRQ priority is limit by max syscall ( smaller is higher )
NVIC_SetPriority(USB_0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY);
NVIC_SetPriority(USB_1_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY);
NVIC_SetPriority(USB_2_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY);
NVIC_SetPriority(USB_3_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. */
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);
// 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_PA24H_USB_DM);
gpio_set_pin_function(PIN_PA25, PINMUX_PA25H_USB_DP);
#if CFG_TUH_ENABLED
#if defined(CFG_TUH_MAX3421) && CFG_TUH_MAX3421
max3421_init();
#else
// VBUS Power
board_vbus_set(0, true);
#endif
#endif
}
void board_init_after_tusb(void) {
}
//--------------------------------------------------------------------+
// Board porting API
//--------------------------------------------------------------------+
void board_led_write(bool state) {
gpio_set_pin_level(LED_PIN, state);
}
uint32_t board_button_read(void) {
// button is active low
#ifdef BUTTON_PIN
return gpio_get_pin_level(BUTTON_PIN) ? 0 : 1;
#else
return 0;
#endif
}
size_t board_get_unique_id(uint8_t id[], size_t max_len) {
(void) max_len;
uint32_t did_addr[4] = {0x008061FC, 0x00806010, 0x00806014, 0x00806018};
for (int i = 0; i < 4; i++) {
uint32_t did = *((uint32_t const*) did_addr[i]);
did = TU_BSWAP32(did); // swap endian to match samd51 uf2 bootloader
memcpy(id + i * 4, &did, sizeof(uint32_t));
}
return 16;
}
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;
}
#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;
}
#if 0
/* Initialize SERCOM2 for 115200 bps 8N1 using a 48 MHz clock */
static inline void uart_init(void) {
gpio_set_pin_function(PIN_PB24, PINMUX_PB24D_SERCOM2_PAD1);
gpio_set_pin_function(PIN_PB25, PINMUX_PB25D_SERCOM2_PAD0);
MCLK->APBBMASK.bit.SERCOM2_ = 1;
GCLK->PCHCTRL[SERCOM2_GCLK_ID_CORE].reg = GCLK_PCHCTRL_GEN_GCLK0 | GCLK_PCHCTRL_CHEN;
BOARD_SERCOM->USART.CTRLA.bit.SWRST = 1; /* reset and disable SERCOM -> enable configuration */
while (BOARD_SERCOM->USART.SYNCBUSY.bit.SWRST);
BOARD_SERCOM->USART.CTRLA.reg =
SERCOM_USART_CTRLA_SAMPR(0) | /* 0 = 16x / arithmetic baud rate, 1 = 16x / fractional baud rate */
SERCOM_USART_CTRLA_SAMPA(0) | /* 16x over sampling */
SERCOM_USART_CTRLA_FORM(0) | /* 0x0 USART frame, 0x1 USART frame with parity, ... */
SERCOM_USART_CTRLA_DORD | /* LSB first */
SERCOM_USART_CTRLA_MODE(1) | /* 0x0 USART with external clock, 0x1 USART with internal clock */
SERCOM_USART_CTRLA_RXPO(1) | /* SERCOM PAD[1] is used for data reception */
SERCOM_USART_CTRLA_TXPO(0); /* SERCOM PAD[0] is used for data transmission */
BOARD_SERCOM->USART.CTRLB.reg = /* RXEM = 0 -> receiver disabled, LINCMD = 0 -> normal USART transmission, SFDE = 0 -> start-of-frame detection disabled, SBMODE = 0 -> one stop bit, CHSIZE = 0 -> 8 bits */
SERCOM_USART_CTRLB_TXEN | /* transmitter enabled */
SERCOM_USART_CTRLB_RXEN; /* receiver enabled */
// BOARD_SERCOM->USART.BAUD.reg = SERCOM_USART_BAUD_FRAC_FP(0) | SERCOM_USART_BAUD_FRAC_BAUD(26); /* 48000000/(16*115200) = 26.041666667 */
BOARD_SERCOM->USART.BAUD.reg = SERCOM_USART_BAUD_BAUD(63019); /* 65536*(1−16*115200/48000000) */
BOARD_SERCOM->USART.CTRLA.bit.ENABLE = 1; /* activate SERCOM */
while (BOARD_SERCOM->USART.SYNCBUSY.bit.ENABLE); /* wait for SERCOM to be ready */
}
static inline void uart_send_buffer(uint8_t const* text, size_t len) {
for (size_t i = 0; i < len; ++i) {
BOARD_SERCOM->USART.DATA.reg = text[i];
while ((BOARD_SERCOM->USART.INTFLAG.reg & SERCOM_USART_INTFLAG_TXC) == 0);
}
}
static inline void uart_send_str(const char* text) {
while (*text) {
BOARD_SERCOM->USART.DATA.reg = *text++;
while ((BOARD_SERCOM->USART.INTFLAG.reg & SERCOM_USART_INTFLAG_TXC) == 0);
}
}
#endif
#endif
//--------------------------------------------------------------------+
// API: SPI transfer with MAX3421E, must be implemented by application
//--------------------------------------------------------------------+
#if CFG_TUH_ENABLED && 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;
struct {
volatile uint32_t* mck_apb;
uint32_t mask;
uint8_t gclk_id_core;
uint8_t gclk_id_slow;
} const sercom_clock[] = {
{ &MCLK->APBAMASK.reg, MCLK_APBAMASK_SERCOM0, SERCOM0_GCLK_ID_CORE, SERCOM0_GCLK_ID_SLOW },
{ &MCLK->APBAMASK.reg, MCLK_APBAMASK_SERCOM1, SERCOM1_GCLK_ID_CORE, SERCOM1_GCLK_ID_SLOW },
{ &MCLK->APBBMASK.reg, MCLK_APBBMASK_SERCOM2, SERCOM2_GCLK_ID_CORE, SERCOM2_GCLK_ID_SLOW },
{ &MCLK->APBBMASK.reg, MCLK_APBBMASK_SERCOM3, SERCOM3_GCLK_ID_CORE, SERCOM3_GCLK_ID_SLOW },
{ &MCLK->APBDMASK.reg, MCLK_APBDMASK_SERCOM4, SERCOM4_GCLK_ID_CORE, SERCOM4_GCLK_ID_SLOW },
{ &MCLK->APBDMASK.reg, MCLK_APBDMASK_SERCOM5, SERCOM5_GCLK_ID_CORE, SERCOM5_GCLK_ID_SLOW },
#ifdef SERCOM6_GCLK_ID_CORE
{ &MCLK->APBDMASK.reg, MCLK_APBDMASK_SERCOM6, SERCOM6_GCLK_ID_CORE, SERCOM6_GCLK_ID_SLOW },
#endif
#ifdef SERCOM7_GCLK_ID_CORE
{ &MCLK->APBDMASK.reg, MCLK_APBDMASK_SERCOM7, SERCOM7_GCLK_ID_CORE, SERCOM7_GCLK_ID_SLOW },
#endif
};
Sercom* sercom = MAX3421_SERCOM;
// Enable the APB clock for SERCOM
*sercom_clock[MAX3421_SERCOM_ID].mck_apb |= sercom_clock[MAX3421_SERCOM_ID].mask;
// Configure GCLK for SERCOM
GCLK->PCHCTRL[sercom_clock[MAX3421_SERCOM_ID].gclk_id_core].reg =
GCLK_PCHCTRL_GEN_GCLK0_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
GCLK->PCHCTRL[sercom_clock[MAX3421_SERCOM_ID].gclk_id_slow].reg =
GCLK_PCHCTRL_GEN_GCLK3_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
// 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
uint8_t baud_reg = (uint8_t) (SystemCoreClock / (2 * baudrate));
if (baud_reg) {
baud_reg--;
}
sercom->SPI.BAUD.reg = baud_reg;
// Configure PA12 as MOSI (PAD0), PA13 as SCK (PAD1), PA14 as MISO (PAD2), function C (sercom)
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 -------------//
// Enable the APB clock for EIC (External Interrupt Controller)
MCLK->APBAMASK.reg |= MCLK_APBAMASK_EIC;
// Configure GCLK for EIC
GCLK->PCHCTRL[EIC_GCLK_ID].reg = GCLK_PCHCTRL_GEN_GCLK0_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
// Configure PA20 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->CTRLA.bit.ENABLE = 0;
while (EIC->SYNCBUSY.bit.ENABLE);
// Configure EIC to trigger on falling edge
volatile uint32_t* eic_config;
uint8_t sense_shift;
if (MAX3421_INTR_EIC_ID < 8) {
eic_config = &EIC->CONFIG[0].reg;
sense_shift = MAX3421_INTR_EIC_ID * 4;
} else {
eic_config = &EIC->CONFIG[1].reg;
sense_shift = (MAX3421_INTR_EIC_ID - 8) * 4;
}
*eic_config &= ~(7 << sense_shift);
*eic_config |= 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_0_IRQn + MAX3421_INTR_EIC_ID, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY);
#endif
// Enable External Interrupt
EIC->INTENSET.reg = EIC_INTENSET_EXTINT(1 << MAX3421_INTR_EIC_ID);
// Enable EIC
EIC->CTRLA.bit.ENABLE = 1;
while (EIC->SYNCBUSY.bit.ENABLE);
}
void MAX3421_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;
const IRQn_Type irq = EIC_0_IRQn + MAX3421_INTR_EIC_ID;
if (enabled) {
NVIC_EnableIRQ(irq);
} else {
NVIC_DisableIRQ(irq);
}
}
// 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
void HardFault_Handler(void) {
__BKPT(0);
while (1);
}
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