From 58f17ba344b3c0915f1f370b587240cad230cae3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A1szl=C3=B3=20Monda?= <laci@monda.hu>
Date: Thu, 10 Aug 2017 18:04:09 +0200
Subject: [PATCH] Remove microseconds_sysclk.c because we'll use the PIT
 instead for maintaining time.

---
 .../buspal/microseconds/microseconds_sysclk.c | 131 ------------------
 1 file changed, 131 deletions(-)
 delete mode 100644 right/src/buspal/microseconds/microseconds_sysclk.c

diff --git a/right/src/buspal/microseconds/microseconds_sysclk.c b/right/src/buspal/microseconds/microseconds_sysclk.c
deleted file mode 100644
index 387ce6b..0000000
--- a/right/src/buspal/microseconds/microseconds_sysclk.c
+++ /dev/null
@@ -1,131 +0,0 @@
-/*
- * @file microseconds_sysclk.c
- * @brief Microseconds sysclk timer driver source file
- *
- * Notes: The driver configure sysclk as lifetime timer
- */
-#include "microseconds/microseconds.h"
-#include "fsl_device_registers.h"
-#include <stdarg.h>
-
-////////////////////////////////////////////////////////////////////////////////
-// Definitions
-////////////////////////////////////////////////////////////////////////////////
-
-enum
-{
-    kFrequency_1MHz = 1000000UL
-};
-
-////////////////////////////////////////////////////////////////////////////////
-// Variables
-////////////////////////////////////////////////////////////////////////////////
-//! @brief Tracks number of timer rollovers for extended time keeping
-//!        with 32 bits here + the 24 bits of the counter for lower resolution
-//!        it will be years worth of time
-volatile uint32_t s_highCounter;
-uint32_t s_tickPerMicrosecondMul8; //!< This value equal to 8 times ticks per microseconds
-
-////////////////////////////////////////////////////////////////////////////////
-// Code
-////////////////////////////////////////////////////////////////////////////////
-
-//! @brief Initialize and start the timer facilities using the SysTick.
-void microseconds_init(void)
-{
-    s_highCounter = 0;
-    SysTick->LOAD = SysTick_LOAD_RELOAD_Msk; // Set reload register to max value
-    SysTick->VAL = 0;                        // As per ARM reference initialization, set initial value to 0
-                                             //  interrupts are only triggered when going from 1 to 0
-
-    SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk | // Set timer to core clock frequency
-                    SysTick_CTRL_TICKINT_Msk |   // Enable interrupts on timeout
-                    SysTick_CTRL_ENABLE_Msk;     // Enable SysTick IRQ and SysTick Timer
-
-    /* Calculate this value early
-     * The reason why use this solution is that lowest clock frequency supported by L0PB and L4KS
-     * is 0.25MHz, this solution will make sure ticks per microscond is greater than 0.
-     */
-    s_tickPerMicrosecondMul8 = (SystemCoreClock * 8) / kFrequency_1MHz;
-
-    // Make sure this value is greater than 0
-    if (!s_tickPerMicrosecondMul8)
-    {
-        s_tickPerMicrosecondMul8 = 1;
-    }
-}
-
-//! @brief Shutdown the microsecond timer
-void microseconds_shutdown(void)
-{
-    // Disable the timer and interrupts from it
-    SysTick->CTRL = SysTick->CTRL & ~(SysTick_CTRL_CLKSOURCE_Msk | SysTick_CTRL_TICKINT_Msk | SysTick_CTRL_ENABLE_Msk);
-
-    // Clear the current value register
-    SysTick->VAL = 0;
-}
-
-//! @brief Read back the running tick count
-uint64_t microseconds_get_ticks(void)
-{
-    uint64_t retVal;
-
-    //! The rollover counter keeps track of increments higher than the 24 bit SysTick counter
-    //! to combine them shift rollover up 24 bits and add the current ticks
-    uint32_t high;
-    uint32_t low;
-
-    // Check for an overflow condition between the two reads above
-    do
-    {
-        high = s_highCounter;
-        low = ~SysTick->VAL & SysTick_LOAD_RELOAD_Msk;
-    } while (high != s_highCounter);
-
-    retVal = ((uint64_t)high << 24) + low;
-
-    return retVal;
-}
-
-//! @brief Returns the conversion of ticks to actual microseconds
-//!        This is used to seperate any calculations from getting a timer
-//         value for timing sensitive scenarios
-uint32_t microseconds_convert_to_microseconds(uint32_t ticks)
-{
-    // return the total ticks divided by the number of Mhz the system clock is at to give microseconds
-    return (8 * ticks / s_tickPerMicrosecondMul8); //!< Assumes system clock will never be < 0.125 Mhz
-}
-
-//! @brief Returns the conversion of microseconds to ticks
-uint64_t microseconds_convert_to_ticks(uint32_t microseconds)
-{
-    return ((uint64_t)microseconds * s_tickPerMicrosecondMul8 / 8);
-}
-
-//! @brief Delay specified time
-//!
-//! @param us Delay time in microseconds unit
-void microseconds_delay(uint32_t us)
-{
-    uint64_t currentTicks = microseconds_get_ticks();
-
-    //! The clock value in Mhz = ticks/microsecond
-    uint64_t ticksNeeded = ((uint64_t)us * s_tickPerMicrosecondMul8 / 8) + currentTicks;
-    while (microseconds_get_ticks() < ticksNeeded)
-    {
-        ;
-    }
-}
-
-//! @brief Gets the clock value used for microseconds driver
-uint32_t microseconds_get_clock(void)
-{
-    return SystemCoreClock;
-}
-
-//! @brief Interrupt handler for the SysTick timer, this will just increment
-//         the rollover counter for extended time keeping
-void SysTick_Handler(void)
-{
-    s_highCounter++;
-}