Pull out systick code into system.c

Makefile

@@ -1,8 +1,8 @@
 PROJECT := main
 BUILD_DIR := bin
 
-# CFILES := main.c
-CFILES += $(wildcard *.c)
+CFILES := main.c system.c
+# CFILES += $(wildcard *.c)
 OPENCM3_DIR := ./libopencm3
 
 # Check if libopencm3 is available before including anything

main.c

@@ -4,42 +4,13 @@
 #include <libopencm3/stm32/gpio.h>
 #include <libopencm3/stm32/rcc.h>
 #include <stdint.h>
-
-volatile uint64_t ticks;
+#include "system.h"
 
 static void gpio_setup(void) {
     rcc_periph_clock_enable(RCC_GPIOC);
     gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO13);
 }
 
-void sys_tick_handler(void) { ticks++; }
-
-static void sys_tick_setup(void) {
-    ticks = 0;
-    // rcc_clock_setup_pll(&rcc_hse_configs[RCC_CLOCK_HSE16_72MHZ]);
-
-    // systick_set_clocksource(STK_CSR_CLKSOURCE_AHB_DIV8);
-    systick_set_clocksource(STK_CSR_CLKSOURCE_AHB);
-
-    // systick_set_reload(48000 - 1);
-    systick_set_frequency(1000, 72000000);
-
-    systick_clear();
-
-    systick_interrupt_enable();
-    systick_counter_enable();
-
-    return;
-}
-
-static uint64_t sys_ticks_get(void) { return ticks; }
-
-static void delay(volatile uint32_t count) {
-    while (count-- > 0) {
-        __asm__("nop");
-    }
-}
-
 int main(void) {
     rcc_clock_setup_pll(&rcc_hse_configs[RCC_CLOCK_HSE8_72MHZ]);
     // rcc_clock_setup_pll(&rcc_hse_configs[RCC_CLOCK_HSI_48MHZ]);

system.c

@@ -2,30 +2,19 @@
 #include <libopencm3/cm3/systick.h>
 #include <stdint.h>
 
-volatile uint64_t ticks = 0;
+volatile uint64_t ticks;
 
 void sys_tick_handler(void) { ticks++; }
 
-uint64_t get_ticks(void) { return ticks; }
-
-void systick_setup(void) {
-    // systick_set_frequency(1000, 72000000);
-    systick_set_clocksource(STK_CSR_CLKSOURCE_AHB);
-    systick_set_reload(72000000 / 1000 - 1); // 1ms tick
-    systick_clear();
-    systick_interrupt_enable();
-    systick_counter_enable();
-}
+uint64_t sys_ticks_get(void) { return ticks; }
 
 void sys_tick_setup(void) {
+    /* Make sure clocks are setup */
     ticks = 0;
-    // rcc_clock_setup_pll(&rcc_hse_configs[RCC_CLOCK_HSE16_72MHZ]);
 
-    // systick_set_clocksource(STK_CSR_CLKSOURCE_AHB_DIV8);
     systick_set_clocksource(STK_CSR_CLKSOURCE_AHB);
-
-    // systick_set_reload(8999);
     systick_set_frequency(1000, 72000000);
+
     systick_clear();
 
     systick_interrupt_enable();
@@ -33,3 +22,8 @@ void sys_tick_setup(void) {
 
     return;
 }
+
+void delay_ms(uint64_t ms) {
+    uint64_t start = sys_ticks_get();
+    while ((sys_ticks_get() - start) < ms);
+}

system.h

@@ -1,6 +1,8 @@
 #pragma once
 #include <stdint.h>
 
-void sys_tick_handler(void);
-uint64_t get_ticks(void);
-void systick_setup(void);
+void     sys_tick_handler(void);
+uint64_t sys_get_ticks(void);
+void     sys_tick_setup(void);
+uint64_t sys_ticks_get(void);
+void     delay_ms(uint64_t ms);