/*****************************************************************************
* Product: DPP example, NUCLEO-L053R8 board, CMSIS-RTOS RTX
* Last Updated for Version: 5.5.0
* Date of the Last Update:  2015-08-20
*
*                    Q u a n t u m     L e a P s
*                    ---------------------------
*                    innovating embedded systems
*
* Copyright (C) Quantum Leaps, LLC. All rights reserved.
*
* This program is open source software: you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published
* by the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Alternatively, this program may be distributed and modified under the
* terms of Quantum Leaps commercial licenses, which expressly supersede
* the GNU General Public License and are specifically designed for
* licensees interested in retaining the proprietary status of their code.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Contact information:
* http://www.state-machine.com
* mailto:info@state-machine.com
*****************************************************************************/
#include "qpc.h"
#include "dpp.h"
#include "bsp.h"

#include "stm32l0xx.h"  /* CMSIS-compliant header file for the MCU used */
/* add other drivers if necessary... */

Q_DEFINE_THIS_FILE

/* Local-scope defines -----------------------------------------------------*/
/* LED pins available on the board (just one user LED LD2--Green on PA.5) */
#define LED_LD2  (1U << 5)

/* Button pins available on the board (just one user Button B1 on PC.13) */
#define BTN_B1   (1U << 13)


static uint32_t l_rnd;  /* random seed */

#ifdef Q_SPY
    /* event-source identifiers used for tracing */
    static uint8_t const l_rtx_ticker = 0U;
    static uint8_t const l_EXTI0_IRQHandler = 0U;

    enum AppRecords { /* application-specific trace records */
        PHILO_STAT = QS_USER
    };

#endif

/* ISRs used in this project ===============================================*/
/* example ISR handler for CMSIS-RTX */
void EXTI0_IRQHandler(void); /* prototype */
void EXTI0_IRQHandler(void) {
    QACTIVE_POST(AO_Table, Q_NEW(QEvt, MAX_SIG), /* for testing... */
                 &l_EXTI0_IRQHandler);
    /* NOTE:
    * There is no need to explicitly pend the PendSV exception, because
    * RTX handles this when signaling the task. (See OS_PEND_IRQ() macro
    * in RTX source code).
    */
}

/* RTX callbacks ===========================================================*/
void os_idle_demon(void); /* prototype */
void os_idle_demon(void) {
    /* The idle demon is a system thread, running when no other thread is
    * ready to run.
    */

    for (;;) { /*  idle loop */

        /* toggle an LED on and then off (not enough LEDs, see NOTE01) */
        QF_INT_DISABLE();
        //GPIOA->BSRR |= (LED_LD2);         /* turn LED[n] on  */
        //GPIOA->BSRR |= (LED_LD2 << 16);   /* turn LED[n] off */
        QF_INT_ENABLE();

#ifdef Q_SPY
        if ((USART2->ISR & 0x0080U) != 0) { /* is TXE empty? */
            uint16_t b;

            QF_INT_DISABLE();
            b = QS_getByte();
            QF_INT_ENABLE();

            if (b != QS_EOD) {  /* not End-Of-Data? */
                USART2->TDR  = (b & 0xFFU); /* put into the DR register */
            }
        }
#elif defined NDEBUG
        /* Put the CPU and peripherals to the low-power mode.
        * you might need to customize the clock management for your application,
        * see the datasheet for your particular Cortex-M3 MCU.
        */
        /* !!!CAUTION!!!
        * The WFI instruction stops the CPU clock, which unfortunately disables
        * the JTAG port, so the ST-Link debugger can no longer connect to the
        * board. For that reason, the call to __WFI() has to be used with CAUTION.
        *
        * NOTE: If you find your board "frozen" like this, strap BOOT0 to VDD and
        * reset the board, then connect with ST-Link Utilities and erase the part.
        * The trick with BOOT(0) is it gets the part to run the System Loader
        * instead of your broken code. When done disconnect BOOT0, and start over.
        */
        //__WFI(); /* Wait-For-Interrupt */
#endif
    } /* idle loop */
}
/*..........................................................................*/
/* This function is called when RTX detects a runtime error.
* Parameter 'error_code' holds the runtime error code.
*/
void os_error(uint32_t err_code); /* prototype */
void os_error(uint32_t error_code) {
    /* perform customized error handling...  */
    Q_ERROR_ID(error_code);  /* NOTE: does not return */
}


/* BSP functions ===========================================================*/
void BSP_init(void) {
    /* NOTE: SystemInit() has been already called from the startup code
    *  but SystemCoreClock needs to be updated
    */
    SystemCoreClockUpdate();

    /* enable GPIOA clock port for the LED LD2 */
    RCC->IOPENR |= (1U << 0);

    /* configure LED (PA.5) pin as push-pull output, no pull-up, pull-down */
    GPIOA->MODER   &= ~((3U << 2*5));
    GPIOA->MODER   |=  ((1U << 2*5));
    GPIOA->OTYPER  &= ~((1U <<   5));
    GPIOA->OSPEEDR &= ~((3U << 2*5));
    GPIOA->OSPEEDR |=  ((1U << 2*5));
    GPIOA->PUPDR   &= ~((3U << 2*5));

    /* enable GPIOC clock port for the Button B1 */
    RCC->IOPENR |=  (1U << 2);

    /* configure Button (PC.13) pins as input, no pull-up, pull-down */
    GPIOC->MODER   &= ~(3U << 2*13);
    GPIOC->OSPEEDR &= ~(3U << 2*13);
    GPIOC->OSPEEDR |=  (1U << 2*13);
    GPIOC->PUPDR   &= ~(3U << 2*13);

    BSP_randomSeed(1234U); /* seed the random number generator */

    /* initialize the QS software tracing... */
    if (QS_INIT((void *)0) == 0U) {
        Q_ERROR();
    }
    QS_OBJ_DICTIONARY(&l_rtx_ticker);
    QS_OBJ_DICTIONARY(&l_EXTI0_IRQHandler);
}
/*..........................................................................*/
void BSP_displayPhilStat(uint8_t n, char const *stat) {
    if (stat[0] == 'h') {
        GPIOA->BSRR |= LED_LD2;  /* turn LED on  */
    }
    else {
        GPIOA->BSRR |= (LED_LD2 << 16);  /* turn LED off */
    }

    QS_BEGIN(PHILO_STAT, AO_Philo[n]) /* application-specific record begin */
        QS_U8(1, n);                  /* Philosopher number */
        QS_STR(stat);                 /* Philosopher status */
    QS_END()
}
/*..........................................................................*/
void BSP_displayPaused(uint8_t paused) {
    /* not enough LEDs to implement this feature */
    if (paused != (uint8_t)0) {
        //GPIOA->BSRR |= (LED_LD2);  /* turn LED[n] on  */
    }
    else {
        //GPIOA->BSRR |= (LED_LD2 << 16);  /* turn LED[n] off */
    }
}
/*..........................................................................*/
uint32_t BSP_random(void) { /* a very cheap pseudo-random-number generator */
    /* "Super-Duper" Linear Congruential Generator (LCG)
    * LCG(2^32, 3*7*11*13*23, 0, seed)
    */
    l_rnd = l_rnd * (3U*7U*11U*13U*23U);
    return l_rnd >> 8;
}
/*..........................................................................*/
void BSP_randomSeed(uint32_t seed) {
    l_rnd = seed;
}
/*..........................................................................*/
void BSP_terminate(int16_t result) {
    (void)result;
}

/* QF callbacks ============================================================*/
void QF_onStartup(void) {
    /* configure the QF ticker thread */
    QF_setRtxTicker(1000U/BSP_TICKS_PER_SEC, osPriorityAboveNormal);

    /* set priorities of ISRs used in the system... */
    NVIC_SetPriority(EXTI0_1_IRQn,   1U);
    /* ... */

    /* enable IRQs in the NVIC... */
    NVIC_EnableIRQ(EXTI0_1_IRQn);
    /* ... */
}
/*..........................................................................*/
void QF_onCleanup(void) {
}
/*..........................................................................*/
void QF_onRtxTicker() {
    /* state of the button debouncing, see below */
    static struct ButtonsDebouncing {
        uint32_t depressed;
        uint32_t previous;
    } buttons = { ~0U, ~0U };
    uint32_t current;
    uint32_t tmp;

    QF_TICK_X(0U, &l_rtx_ticker); /* process time events for rate 0 */

    /* Perform the debouncing of buttons. The algorithm for debouncing
    * adapted from the book "Embedded Systems Dictionary" by Jack Ganssle
    * and Michael Barr, page 71.
    */
    current = ~GPIOC->IDR; /* read Port C with the state of Button B1 */
    tmp = buttons.depressed; /* save the debounced depressed buttons */
    buttons.depressed |= (buttons.previous & current); /* set depressed */
    buttons.depressed &= (buttons.previous | current); /* clear released */
    buttons.previous   = current; /* update the history */
    tmp ^= buttons.depressed;     /* changed debounced depressed */
    if ((tmp & BTN_B1) != 0U) {  /* debounced B1 state changed? */
        if ((buttons.depressed & BTN_B1) != 0U) { /* is B1 depressed? */
            static QEvt const pauseEvt = { PAUSE_SIG, 0U, 0U};
            QF_PUBLISH(&pauseEvt, &l_rtx_ticker);
        }
        else {            /* the button is released */
            static QEvt const serveEvt = { SERVE_SIG, 0U, 0U};
            QF_PUBLISH(&serveEvt, &l_rtx_ticker);
        }
    }
}

/*..........................................................................*/
void Q_onAssert(char const *module, int loc) {
    /*
    * NOTE: add here your application-specific error handling
    */
    (void)module;
    (void)loc;
    QS_ASSERTION(module, loc, (uint32_t)10000U); /* report assertion to QS */
    NVIC_SystemReset();
}

/* QS callbacks ============================================================*/
#ifdef Q_SPY
/*..........................................................................*/
#define __DIV(__PCLK, __BAUD)       (((__PCLK / 4) *25)/(__BAUD))
#define __DIVMANT(__PCLK, __BAUD)   (__DIV(__PCLK, __BAUD)/100)
#define __DIVFRAQ(__PCLK, __BAUD)   \
    (((__DIV(__PCLK, __BAUD) - (__DIVMANT(__PCLK, __BAUD) * 100)) \
        * 16 + 50) / 100)
#define __USART_BRR(__PCLK, __BAUD) \
    ((__DIVMANT(__PCLK, __BAUD) << 4)|(__DIVFRAQ(__PCLK, __BAUD) & 0x0F))

uint8_t QS_onStartup(void const *arg) {
    static uint8_t qsBuf[1024]; /* buffer for QS */

    (void)arg; /* avoid the "unused parameter" compiler warning */
    QS_initBuf(qsBuf, sizeof(qsBuf));

    /* enable peripheral clock for USART2 */
    RCC->IOPENR  |= ( 1U <<  0);   /* Enable GPIOA clock   */
    RCC->APB1ENR |= ( 1U << 17);   /* Enable USART#2 clock */

    /* Configure PA3 to USART2_RX, PA2 to USART2_TX */
    GPIOA->AFR[0] &= ~((15U << 4* 3) | (15ul << 4* 2) );
    GPIOA->AFR[0] |=  (( 4U << 4* 3) | ( 4ul << 4* 2) );
    GPIOA->MODER  &= ~(( 3U << 2* 3) | ( 3ul << 2* 2) );
    GPIOA->MODER  |=  (( 2U << 2* 3) | ( 2ul << 2* 2) );

    USART2->BRR  = __USART_BRR(SystemCoreClock, 115200U);  /* baud rate */
    USART2->CR3  = 0x0000U;       /* no flow control */
    USART2->CR2  = 0x0000U;       /* 1 stop bit      */
    USART2->CR1  = ((1U <<  2) |  /* enable RX       */
                    (1U <<  3) |  /* enable TX       */
                    (0U << 12) |  /* 8 data bits     */
                    (0U << 28) |  /* 8 data bits     */
                    (1U <<  0) ); /* enable USART    */

    /* setup the QS filters... */
    QS_FILTER_ON(QS_QEP_STATE_ENTRY);
    QS_FILTER_ON(QS_QEP_STATE_EXIT);
    QS_FILTER_ON(QS_QEP_STATE_INIT);
    QS_FILTER_ON(QS_QEP_INIT_TRAN);
    QS_FILTER_ON(QS_QEP_INTERN_TRAN);
    QS_FILTER_ON(QS_QEP_TRAN);
    QS_FILTER_ON(QS_QEP_IGNORED);
    QS_FILTER_ON(QS_QEP_DISPATCH);
    QS_FILTER_ON(QS_QEP_UNHANDLED);

    QS_FILTER_ON(PHILO_STAT);

    return (uint8_t)1; /* return success */
}
/*..........................................................................*/
void QS_onCleanup(void) {
}
/*..........................................................................*/
QSTimeCtr QS_onGetTime(void) { /* NOTE: invoked with interrupts DISABLED */
    /* NOTE:
    * QS_onGetTime() cannot call the offical RTX osKernelSysTick() service,
    * because osKernelSysTick() is a SVC function, which can't execute
    * with interrupts disabled. Therefore, QS_onGetTime() calls directly
    * the function svcKernelSysTick().
    */
    uint32_t svcKernelSysTick(void); /* prototype declaration */
    return (QSTimeCtr)svcKernelSysTick();
}
/*..........................................................................*/
void QS_onFlush(void) {
    uint16_t b;

    QF_INT_DISABLE();
    while ((b = QS_getByte()) != QS_EOD) {    /* while not End-Of-Data... */
        QF_INT_ENABLE();
        while ((USART2->ISR & 0x0080U) == 0U) { /* while TXE not empty */
        }
        USART2->TDR  = (b & 0xFFU);  /* put into the DR register */
    }
    QF_INT_ENABLE();
}
#endif /* Q_SPY */
/*--------------------------------------------------------------------------*/

/*****************************************************************************
* NOTE01:
* The User LED is used to visualize the idle loop activity. The brightness
* of the LED is proportional to the frequency of invcations of the idle loop.
* Please note that the LED is toggled with interrupts locked, so no interrupt
* execution time contributes to the brightness of the User LED.
*/