///***************************************************************************
// Product: DPP example, EK-TM4C123GXL board, cooperative QV kernel
// Last updated for version 5.9.5
// Last updated on  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 <www.gnu.org/licenses/>.
//
// Contact information:
// https://state-machine.com
// <info@state-machine.com>
//****************************************************************************
#include "qpcpp.hpp"
#include "dpp.hpp"
#include "bsp.hpp"

#include "TM4C123GH6PM.h"        // the device specific header (TI)
#include "rom.h"                 // the built-in ROM functions (TI)
#include "sysctl.h"              // system control driver (TI)
#include "gpio.h"                // GPIO driver (TI)
// 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
    UART0_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 {
    GPIOA_PRIO = QF_AWARE_ISR_CMSIS_PRI, // see NOTE00
    SYSTICK_PRIO,
    // ...
    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_RED     (1U << 1)
#define LED_GREEN   (1U << 3)
#define LED_BLUE    (1U << 2)

#define BTN_SW1     (1U << 4)
#define BTN_SW2     (1U << 0)

static uint32_t l_rnd; // random seed

#ifdef Q_SPY

    QP::QSTimeCtr QS_tickTime_;
    QP::QSTimeCtr QS_tickPeriod_;
    static uint8_t l_SysTick_Handler;
    static uint8_t l_GPIOPortA_IRQHandler;

    #define UART_BAUD_RATE      115200U
    #define UART_FR_TXFE        (1U << 7)
    #define UART_FR_RXFE        (1U << 4)
    #define UART_TXFIFO_DEPTH   16U

    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;

#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_Handler); // 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 = ~GPIOF->DATA_Bits[BTN_SW1 | BTN_SW2]; // read SW1 and SW2
    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_SW1) != 0U) {  // debounced SW1 state changed?
        if ((buttons.depressed & BTN_SW1) != 0U) { // is SW1 depressed?
            static QP::QEvt const pauseEvt = { DPP::PAUSE_SIG, 0U, 0U};
            QP::QF::PUBLISH(&pauseEvt, &l_SysTick_Handler);
        }
        else {            // the button is released
            static QP::QEvt const serveEvt = { DPP::SERVE_SIG, 0U, 0U};
            QP::QF::PUBLISH(&serveEvt, &l_SysTick_Handler);
        }
    }
}
//............................................................................
void GPIOPortA_IRQHandler(void);  // prototype
void GPIOPortA_IRQHandler(void) {
    // for testing..
    DPP::AO_Table->POST(Q_NEW(QP::QEvt, DPP::MAX_PUB_SIG),
                        &l_GPIOPortA_IRQHandler);
}

//............................................................................
void UART0_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 UART0_IRQHandler(void) {
    uint32_t status = UART0->RIS; // get the raw interrupt status
    UART0->ICR = status;          // clear the asserted interrupts

    while ((UART0->FR & UART_FR_RXFE) == 0) { // while RX FIFO NOT empty
        uint8_t b = static_cast<uint8_t>(UART0->DR);
        QP::QS::rxPut(b);
    }
}
#else
void UART0_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...
    // 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 option should be used with CAUTION.
    //
    FPU->FPCCR &= ~((1U << FPU_FPCCR_ASPEN_Pos) | (1U << FPU_FPCCR_LSPEN_Pos));

    // enable clock for to the peripherals used by this application...
    SYSCTL->RCGCGPIO |= (1U << 5); // enable Run mode for GPIOF

    // configure the LEDs and push buttons
    GPIOF->DIR |= (LED_RED | LED_GREEN | LED_BLUE); // set direction: output
    GPIOF->DEN |= (LED_RED | LED_GREEN | LED_BLUE); // digital enable
    GPIOF->DATA_Bits[LED_RED]   = 0U;  // turn the LED off
    GPIOF->DATA_Bits[LED_GREEN] = 0U;  // turn the LED off
    GPIOF->DATA_Bits[LED_BLUE]  = 0U;  // turn the LED off

    // configure the Buttons
    GPIOF->DIR &= ~(BTN_SW1 | BTN_SW2); //  set direction: input
    ROM_GPIOPadConfigSet(GPIOF_BASE, (BTN_SW1 | BTN_SW2),
                         GPIO_STRENGTH_2MA, GPIO_PIN_TYPE_STD_WPU);

    BSP::randomSeed(1234U);

    if (!QS_INIT((void *)0)) { // initialize the QS software tracing
        Q_ERROR();
    }
    QS_OBJ_DICTIONARY(&l_SysTick_Handler);
    QS_OBJ_DICTIONARY(&l_GPIOPortA_IRQHandler);
    QS_USR_DICTIONARY(PHILO_STAT);
    QS_USR_DICTIONARY(COMMAND_STAT);
}
//............................................................................
void BSP::displayPhilStat(uint8_t n, char const *stat) {
    GPIOF->DATA_Bits[LED_RED]   = ((stat[0] == 'h') ? 0xFFU : 0U);
    GPIOF->DATA_Bits[LED_GREEN] = ((stat[0] == 'e') ? 0xFFU : 0U);

    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) {
    GPIOF->DATA_Bits[LED_RED] = ((paused != 0U) ? 0xFFU : 0U);
}
//............................................................................
uint32_t BSP::random(void) { // a very cheap pseudo-random-number generator
    // The flating point code is to exercise the FPU
    float volatile x = 3.1415926F;
    x = x + 2.7182818F;

    // "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

    return (rnd >> 8);
}
//............................................................................
void BSP::randomSeed(uint32_t seed) {
    l_rnd = seed;
}
//............................................................................
void BSP::ledOn(void) {
    GPIOF->DATA_Bits[LED_RED] = 0xFFU;
}
//............................................................................
void BSP::ledOff(void) {
    GPIOF->DATA_Bits[LED_RED] = 0x00U;
}
//............................................................................
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(UART0_IRQn,     DPP::UART0_PRIO);
    NVIC_SetPriority(SysTick_IRQn,   DPP::SYSTICK_PRIO);
    NVIC_SetPriority(GPIOA_IRQn,     DPP::GPIOA_PRIO);
    // ...

    // enable IRQs...
    NVIC_EnableIRQ(GPIOA_IRQn);
#ifdef Q_SPY
    NVIC_EnableIRQ(UART0_IRQn);  // UART0 interrupt used for QS-RX
#endif
}
//............................................................................
void QF::onCleanup(void) {
}
//............................................................................
void QV::onIdle(void) { // called with interrupts disabled, see NOTE01
    // toggle the User LED on and then off, see NOTE02
    GPIOF->DATA_Bits[LED_BLUE] = 0xFFU;  // turn the Blue LED on
    GPIOF->DATA_Bits[LED_BLUE] = 0U;     // turn the Blue LED off

#ifdef Q_SPY
    QF_INT_ENABLE();

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

    if ((UART0->FR & UART_FR_TXFE) != 0U) {  // TX done?
        uint16_t fifo = UART_TXFIFO_DEPTH;   // max bytes we can accept
        uint8_t const *block;

        QF_INT_DISABLE();
        block = QS::getBlock(&fifo); // try to get next block to transmit
        QF_INT_ENABLE();

        while (fifo-- != 0U) {       // any bytes in the block?
            UART0->DR = *block++;    // put into the FIFO
        }
    }
#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-M MCU.
    //
    QV_CPU_SLEEP();  // atomically go to sleep and enable interrupts
#else
    QF_INT_ENABLE(); // just enable interrupts
#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 Quantum Spy
    static uint8_t qsRxBuf[100];  // buffer for QS receive channel
    uint32_t tmp;

    initBuf(qsBuf, sizeof(qsBuf));
    rxInitBuf(qsRxBuf, sizeof(qsRxBuf));

    // enable clock for UART0 and GPIOA (used by UART0 pins)
    SYSCTL->RCGCUART |= (1U << 0); // enable Run mode for UART0
    SYSCTL->RCGCGPIO |= (1U << 0); // enable Run mode for GPIOA

    // configure UART0 pins for UART operation
    tmp = (1U << 0) | (1U << 1);
    GPIOA->DIR   &= ~tmp;
    GPIOA->SLR   &= ~tmp;
    GPIOA->ODR   &= ~tmp;
    GPIOA->PUR   &= ~tmp;
    GPIOA->PDR   &= ~tmp;
    GPIOA->AMSEL &= ~tmp;  // disable analog function on the pins
    GPIOA->AFSEL |= tmp;   // enable ALT function on the pins
    GPIOA->DEN   |= tmp;   // enable digital I/O on the pins
    GPIOA->PCTL  &= ~0x00U;
    GPIOA->PCTL  |= 0x11U;

    // configure the UART for the desired baud rate, 8-N-1 operation
    tmp = (((SystemCoreClock * 8U) / UART_BAUD_RATE) + 1U) / 2U;
    UART0->IBRD   = tmp / 64U;
    UART0->FBRD   = tmp % 64U;
    UART0->LCRH   = (0x3U << 5); // configure 8-N-1 operation
    UART0->LCRH  |= (0x1U << 4); // enable FIFOs
    UART0->CTL    = (1U << 0)    // UART enable
                    | (1U << 8)  // UART TX enable
                    | (1U << 9); // UART RX enable

    // configure UART interrupts (for the RX channel)
    UART0->IM   |= (1U << 4) | (1U << 6); // enable RX and RX-TO interrupt
    UART0->IFLS |= (0x2U << 2);    // interrupt on RX FIFO half-full
    // NOTE: do not enable the UART0 interrupt yet. Wait till QF_onStartup()

    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_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(DPP::PHILO_STAT);
    QS_FILTER_ON(DPP::COMMAND_STAT);

    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 fifo = UART_TXFIFO_DEPTH; // Tx FIFO depth
    uint8_t const *block;
    QF_INT_DISABLE();
    while ((block = getBlock(&fifo)) != static_cast<uint8_t *>(0)) {
        QF_INT_ENABLE();
        // busy-wait until TX FIFO empty
        while ((UART0->FR & UART_FR_TXFE) == 0U) {
        }

        while (fifo-- != 0U) {    // any bytes in the block?
            UART0->DR = *block++; // put into the TX FIFO
        }
        fifo = UART_TXFIFO_DEPTH; // re-load the Tx FIFO depth
        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_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 QV:onIdle() callback is called with interrupts disabled, because the
// determination of the idle condition might change by any interrupt posting
// an event. QV::onIdle() must internally enable interrupts, ideally
// atomically with putting the CPU to the power-saving mode.
//
// NOTE02:
// 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.
//