///***************************************************************************
// Product: DPP example, STM32F4-Discovery board, preemptive QK kernel
// Last Updated for Version: 5.9.5
// Date of the Last Update:  2017-07-20
//
//                    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:
// https://state-machine.com
// mailto:info@state-machine.com
//****************************************************************************
#include "qpcpp.h"
#include "dpp.h"
#include "bsp.h"

#include "stm32f4xx.h"      // CMSIS-compliant header file for the MCU used
#include "stm32f4xx_exti.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "stm32f4xx_usart.h"
// add other drivers if necessary...

Q_DEFINE_THIS_FILE

// namespace DPP *************************************************************
namespace DPP {

// !!!!!!!!!!!!!!!!!!!!!!!!!!!!! CAUTION !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
// Assign a priority to EVERY ISR explicitly by calling NVIC_SetPriority().
// DO NOT LEAVE THE ISR PRIORITIES AT THE DEFAULT VALUE!
//
enum KernelUnawareISRs { // see NOTE00
    USART2_PRIO,
    // ...
    MAX_KERNEL_UNAWARE_CMSIS_PRI  // keep always last
};
// "kernel-unaware" interrupts can't overlap "kernel-aware" interrupts
Q_ASSERT_COMPILE(MAX_KERNEL_UNAWARE_CMSIS_PRI <= QF_AWARE_ISR_CMSIS_PRI);

enum KernelAwareISRs {
    SYSTICK_PRIO = QF_AWARE_ISR_CMSIS_PRI, // see NOTE00
    // ...
    MAX_KERNEL_AWARE_CMSIS_PRI // keep always last
};
// "kernel-aware" interrupts should not overlap the PendSV priority
Q_ASSERT_COMPILE(MAX_KERNEL_AWARE_CMSIS_PRI <= (0xFF >>(8-__NVIC_PRIO_BITS)));

// Local-scope objects -------------------------------------------------------
#define LED_GPIO_PORT     GPIOD
#define LED_GPIO_CLK      RCC_AHB1Periph_GPIOD

#define LED4_PIN          GPIO_Pin_12
#define LED3_PIN          GPIO_Pin_13
#define LED5_PIN          GPIO_Pin_14
#define LED6_PIN          GPIO_Pin_15

#define BTN_GPIO_PORT     GPIOA
#define BTN_GPIO_CLK      RCC_AHB1Periph_GPIOA
#define BTN_B1            GPIO_Pin_0

static uint32_t l_rnd; // random seed
static QP::QMutex l_rndMutex; // to protect the random number generator

#ifdef Q_SPY

    QP::QSTimeCtr QS_tickTime_;
    QP::QSTimeCtr QS_tickPeriod_;

    // QS source IDs
    static uint8_t const l_SysTick = (uint8_t)0;

    enum AppRecords { // application-specific trace records
        PHILO_STAT = QP::QS_USER,
        COMMAND_STAT
    };

#endif

// ISRs used in this project =================================================
extern "C" {

//............................................................................
void SysTick_Handler(void); // prototype
void SysTick_Handler(void) {
    // 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;

    QK_ISR_ENTRY();   // inform QK about entering an ISR

#ifdef Q_SPY
    {
        tmp = SysTick->CTRL; // clear SysTick_CTRL_COUNTFLAG
        QS_tickTime_ += QS_tickPeriod_; // account for the clock rollover
    }
#endif

    QP::QF::TICK_X(0U, &l_SysTick); // 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 = BTN_GPIO_PORT->IDR; // read BTN GPIO
    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 QP::QEvt const pauseEvt = { DPP::PAUSE_SIG, 0U, 0U};
            QP::QF::PUBLISH(&pauseEvt, &l_SysTick);
        }
        else {            // the button is released
            static QP::QEvt const serveEvt = { DPP::SERVE_SIG, 0U, 0U};
            QP::QF::PUBLISH(&serveEvt, &l_SysTick);
        }
    }

    QK_ISR_EXIT();  // inform QK about exiting an ISR
}

//............................................................................
void USART2_IRQHandler(void); // prototype
#ifdef Q_SPY
// ISR for receiving bytes from the QSPY Back-End
// NOTE: This ISR is "QF-unaware" meaning that it does not interact with
// the QF/QK and is not disabled. Such ISRs don't need to call QK_ISR_ENTRY/
// QK_ISR_EXIT and they cannot post or publish events.
//
void USART2_IRQHandler(void) {
    if ((USART2->SR & USART_SR_RXNE) != 0) {
        uint32_t b = USART2->DR;
        QP::QS::rxPut(b);
    }
}
#else
void USART2_IRQHandler(void) {}
#endif // Q_SPY

} // extern "C"

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

    // configure the FPU usage by choosing one of the options...
#if 1
    // OPTION 1:
    // Use the automatic FPU state preservation and the FPU lazy stacking.
    //
    // NOTE:
    // Use the following setting when FPU is used in more than one task or
    // in any ISRs. This setting is the safest and recommended, but requires
    // extra stack space and CPU cycles.
    //
    FPU->FPCCR |= (1U << FPU_FPCCR_ASPEN_Pos) | (1U << FPU_FPCCR_LSPEN_Pos);
#else
    // OPTION 2:
    // Do NOT to use the automatic FPU state preservation and
    // do NOT to use the FPU lazy stacking.
    //
    // NOTE:
    // Use the following setting when FPU is used in ONE task only and not
    // in any ISR. This setting is very efficient, but if more than one task
    // (or ISR) start using the FPU, this can lead to corruption of the
    // FPU registers. This option should be used with CAUTION.
    //
    FPU->FPCCR &= ~((1U << FPU_FPCCR_ASPEN_Pos) | (1U << FPU_FPCCR_LSPEN_Pos));
#endif

    GPIO_InitTypeDef GPIO_struct;

    // NOTE: SystemInit() already called from the startup code
    //  but SystemCoreClock needs to be updated
    SystemCoreClockUpdate();

    // Explictily Disable the automatic FPU state preservation as well as
    // the FPU lazy stacking
    FPU->FPCCR &= ~((1U << FPU_FPCCR_ASPEN_Pos) | (1U << FPU_FPCCR_LSPEN_Pos));

    // Initialize thr port for the LEDs
    RCC_AHB1PeriphClockCmd(LED_GPIO_CLK , ENABLE);

    // GPIO Configuration for the LEDs...
    GPIO_struct.GPIO_Mode  = GPIO_Mode_OUT;
    GPIO_struct.GPIO_OType = GPIO_OType_PP;
    GPIO_struct.GPIO_PuPd  = GPIO_PuPd_UP;
    GPIO_struct.GPIO_Speed = GPIO_Speed_50MHz;

    GPIO_struct.GPIO_Pin = LED3_PIN;
    GPIO_Init(LED_GPIO_PORT, &GPIO_struct);
    LED_GPIO_PORT->BSRRH = LED3_PIN; // turn LED off

    GPIO_struct.GPIO_Pin = LED4_PIN;
    GPIO_Init(LED_GPIO_PORT, &GPIO_struct);
    LED_GPIO_PORT->BSRRH = LED4_PIN; // turn LED off

    GPIO_struct.GPIO_Pin = LED5_PIN;
    GPIO_Init(LED_GPIO_PORT, &GPIO_struct);
    LED_GPIO_PORT->BSRRH = LED5_PIN; // turn LED off

    GPIO_struct.GPIO_Pin = LED6_PIN;
    GPIO_Init(LED_GPIO_PORT, &GPIO_struct);
    LED_GPIO_PORT->BSRRH = LED6_PIN; // turn LED off

    // Initialize thr port for Button
    RCC_AHB1PeriphClockCmd(BTN_GPIO_CLK , ENABLE);

    // GPIO Configuration for the Button...
    GPIO_struct.GPIO_Pin   = BTN_B1;
    GPIO_struct.GPIO_Mode  = GPIO_Mode_IN;
    GPIO_struct.GPIO_OType = GPIO_OType_PP;
    GPIO_struct.GPIO_PuPd  = GPIO_PuPd_DOWN;
    GPIO_struct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(BTN_GPIO_PORT, &GPIO_struct);

    // seed the random number generator
    randomSeed(1234U);

    if (QS_INIT((void *)0) == 0U) { // initialize the QS software tracing
        Q_ERROR();
    }
    QS_OBJ_DICTIONARY(&l_SysTick);
    QS_USR_DICTIONARY(PHILO_STAT);
    QS_USR_DICTIONARY(COMMAND_STAT);
}
//............................................................................
void BSP::displayPhilStat(uint8_t n, char const *stat) {
    (void)n;

    if (stat[0] == 'h') {
        LED_GPIO_PORT->BSRRL = LED3_PIN; // turn LED on
    }
    else {
        LED_GPIO_PORT->BSRRH = LED3_PIN; // turn LED off
    }
    if (stat[0] == 'e') {
        LED_GPIO_PORT->BSRRL = LED5_PIN; // turn LED on
    }
    else {
        LED_GPIO_PORT->BSRRH = LED5_PIN; // turn LED on
    }

    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) {
    if (paused != 0U) {
        LED_GPIO_PORT->BSRRL = LED4_PIN; // turn LED on
    }
    else {
        LED_GPIO_PORT->BSRRH = LED4_PIN; // turn LED on
    }
}
//............................................................................
uint32_t BSP::random(void) { // a very cheap pseudo-random-number generator
    // Some flating point code is to exercise the VFP...
    float volatile x = 3.1415926F;
    x = x + 2.7182818F;

    l_rndMutex.lock(); // lock the random-seed mutex
    // "Super-Duper" Linear Congruential Generator (LCG)
    // LCG(2^32, 3*7*11*13*23, 0, seed)
    //
    uint32_t rnd = l_rnd * (3U*7U*11U*13U*23U);
    l_rnd = rnd; // set for the next time
    l_rndMutex.unlock(); // unlock the random-seed mutex

    return (rnd >> 8);
}
//............................................................................
void BSP::randomSeed(uint32_t seed) {
    l_rnd = seed;
    l_rndMutex.init(N_PHILO); // ceiling <== maximum Philo priority
}

//............................................................................
void BSP::terminate(int16_t result) {
    (void)result;
}

} // namespace DPP


// namespace QP **************************************************************
namespace QP {

// QF callbacks ==============================================================
void QF::onStartup(void) {
    // set up the SysTick timer to fire at BSP::TICKS_PER_SEC rate
    SysTick_Config(SystemCoreClock / DPP::BSP::TICKS_PER_SEC);

    // assing all priority bits for preemption-prio. and none to sub-prio.
    NVIC_SetPriorityGrouping(0U);

    // set priorities of ALL ISRs used in the system, see NOTE00
    //
    // !!!!!!!!!!!!!!!!!!!!!!!!!!!! CAUTION !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    // Assign a priority to EVERY ISR explicitly by calling NVIC_SetPriority().
    // DO NOT LEAVE THE ISR PRIORITIES AT THE DEFAULT VALUE!
    //
    NVIC_SetPriority(USART2_IRQn,    DPP::USART2_PRIO);
    NVIC_SetPriority(SysTick_IRQn,   DPP::SYSTICK_PRIO);
    // ...

    // enable IRQs...
#ifdef Q_SPY
    NVIC_EnableIRQ(USART2_IRQn); // USART2 interrupt used for QS-RX
#endif
}
//............................................................................
void QF::onCleanup(void) {
}
//............................................................................
void QK::onIdle(void) {
    // toggle the User LED on and then off, see NOTE01
    QF_INT_DISABLE();
    LED_GPIO_PORT->BSRRL = LED6_PIN; // turn LED on
    __NOP(); // wait a little to actually see the LED glow
    __NOP();
    __NOP();
    __NOP();
    LED_GPIO_PORT->BSRRH = LED6_PIN; // turn LED off
    QF_INT_ENABLE();

#ifdef Q_SPY
    QS::rxParse();  // parse all the received bytes

    if ((USART2->SR & USART_FLAG_TXE) != 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->DR = (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
}

//............................................................................
extern "C" void Q_onAssert(char const *module, int loc) {
    //
    // NOTE: add here your application-specific error handling
    //
    (void)module;
    (void)loc;
    QS_ASSERTION(module, loc, static_cast<uint32_t>(10000U));
    NVIC_SystemReset();
}

// QS callbacks ==============================================================
#ifdef Q_SPY
//............................................................................
bool QS::onStartup(void const *arg) {
    static uint8_t qsBuf[2*1024]; // buffer for QS-TX channel
    static uint8_t qsRxBuf[100];  // buffer for QS-RX channel
    GPIO_InitTypeDef GPIO_struct;
    USART_InitTypeDef USART_struct;

    (void)arg; // avoid the "unused parameter" compiler warning
    initBuf(qsBuf, sizeof(qsBuf));
    rxInitBuf(qsRxBuf, sizeof(qsRxBuf));

    // enable peripheral clock for USART2
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);

    // GPIOA clock enable
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

    // GPIOA Configuration:  USART2 TX on PA2 and RX on PA3
    GPIO_struct.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3;
    GPIO_struct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_struct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_struct.GPIO_OType = GPIO_OType_PP;
    GPIO_struct.GPIO_PuPd = GPIO_PuPd_UP ;
    GPIO_Init(GPIOA, &GPIO_struct);

    // Connect USART2 pins to AF2
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_USART2); // TX = PA2
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource3, GPIO_AF_USART2); // RX = PA3

    USART_struct.USART_BaudRate = 115200;
    USART_struct.USART_WordLength = USART_WordLength_8b;
    USART_struct.USART_StopBits = USART_StopBits_1;
    USART_struct.USART_Parity = USART_Parity_No;
    USART_struct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_struct.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
    USART_Init(USART2, &USART_struct);

    USART_ITConfig(USART2, USART_IT_RXNE, ENABLE); // enable RX interrupt
    USART_Cmd(USART2, ENABLE); // enable USART2

    DPP::QS_tickPeriod_ = SystemCoreClock / DPP::BSP::TICKS_PER_SEC;
    DPP::QS_tickTime_ = DPP::QS_tickPeriod_; // to start the timestamp at zero

    // setup the QS filters...
    QS_FILTER_ON(QS_SM_RECORDS); // state machine records
    QS_FILTER_ON(QS_AO_RECORDS); // active object records
    QS_FILTER_ON(QS_UA_RECORDS); // all user records

    return true; // return success
}
//............................................................................
void QS::onCleanup(void) {
}
//............................................................................
QSTimeCtr QS::onGetTime(void) {  // NOTE: invoked with interrupts DISABLED
    if ((SysTick->CTRL & SysTick_CTRL_COUNTFLAG_Msk) == 0) { // not set?
        return DPP::QS_tickTime_ - static_cast<QSTimeCtr>(SysTick->VAL);
    }
    else { // the rollover occured, but the SysTick_ISR did not run yet
        return DPP::QS_tickTime_ + DPP::QS_tickPeriod_
               - static_cast<QSTimeCtr>(SysTick->VAL);
    }
}
//............................................................................
void QS::onFlush(void) {
    uint16_t b;

    QF_INT_DISABLE();
    while ((b = getByte()) != QS_EOD) { // while not End-Of-Data...
        QF_INT_ENABLE();
        // while TXE not empty
        while ((USART2->SR & USART_FLAG_TXE) == 0) { // while TXE not empty
        }
        USART2->DR = (b & 0xFFU); // put into the DR register
        QF_INT_DISABLE();
    }
    QF_INT_ENABLE();
}
//............................................................................
//! callback function to reset the target (to be implemented in the BSP)
void QS::onReset(void) {
    NVIC_SystemReset();
}
//............................................................................
//! callback function to execute a user command (to be implemented in BSP)
extern "C" void assert_failed(char const *module, int loc);
void QS::onCommand(uint8_t cmdId, uint32_t param1,
                   uint32_t param2, uint32_t param3)
{
    (void)cmdId;
    (void)param1;
    (void)param2;
    (void)param3;

    // application-specific record
    QS_BEGIN(DPP::COMMAND_STAT, static_cast<void *>(0))
        QS_U8(2, cmdId);
        QS_U32(8, param1);
        QS_U32(8, param2);
        QS_U32(8, param3);
    QS_END()

    if (cmdId == 10U) {
        assert_failed("QS_onCommand", 11);
    }
}

#endif // Q_SPY
//----------------------------------------------------------------------------

} // namespace QP

//****************************************************************************
// NOTE00:
// The QF_AWARE_ISR_CMSIS_PRI constant from the QF port specifies the highest
// ISR priority that is disabled by the QF framework. The value is suitable
// for the NVIC_SetPriority() CMSIS function.
//
// Only ISRs prioritized at or below the QF_AWARE_ISR_CMSIS_PRI level (i.e.,
// with the numerical values of priorities equal or higher than
// QF_AWARE_ISR_CMSIS_PRI) are allowed to call the QK_ISR_ENTRY/QK_ISR_ENTRY
// macros or any other QF/QK  services. These ISRs are "QF-aware".
//
// Conversely, any ISRs prioritized above the QF_AWARE_ISR_CMSIS_PRI priority
// level (i.e., with the numerical values of priorities less than
// QF_AWARE_ISR_CMSIS_PRI) are never disabled and are not aware of the kernel.
// Such "QF-unaware" ISRs cannot call any QF/QK services. In particular they
// can NOT call the macros QK_ISR_ENTRY/QK_ISR_ENTRY. The only mechanism
// by which a "QF-unaware" ISR can communicate with the QF framework is by
// triggering a "QF-aware" ISR, which can post/publish events.
//
// 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.
//