From ff3a78a64798c8cce7f2a10256a26a3e91c0351c Mon Sep 17 00:00:00 2001
From: Drew Barbier <dbarbi1@gmail.com>
Date: Mon, 2 Jul 2018 15:23:10 -0500
Subject: add busy wait and extra buttons/irq

---
 software/clic_vectored/clic_vectored.c | 68 ++++++++++++++++++++++++++--------
 1 file changed, 52 insertions(+), 16 deletions(-)

(limited to 'software')

diff --git a/software/clic_vectored/clic_vectored.c b/software/clic_vectored/clic_vectored.c
index db2435d..38a564e 100644
--- a/software/clic_vectored/clic_vectored.c
+++ b/software/clic_vectored/clic_vectored.c
@@ -1,5 +1,4 @@
 // See LICENSE for license details.
-
 #include <stdio.h>
 #include <stdlib.h>
 #include "platform.h"
@@ -8,6 +7,7 @@
 #include <unistd.h>
 #include "sifive/devices/clic.h"
 #include "clic/clic_driver.h"
+#include "sifive/devices/clint.h"
 
 #ifndef _SIFIVE_COREPLEXIP_ARTY_H
 #error 'local_interrupts' demo only supported for Core IP Eval Kits
@@ -27,31 +27,34 @@ clic_instance_t clic;
 
 const char * instructions_msg = " \
 \n\
-                         SiFive, Inc\n\
- E21 Core IP Eval Kit 'clic_interrupts' demo.\n\
+              SiFive, Inc\n\
+ E21 Core IP Eval Kit 'clic_vectored' demo.\n\
+ This demo uses buttons 0, 1, and 2 on the\n\
+ Arty board to trigger vectored clic interrupts.\n\
 \n\
-The Buttons 0-3 and Switch 3 are enabled as local\n\
-interrupts sources. A .5 s 'debounce' timer is used \n\
-between these interrupts. Software interrupts are\n\
-used to print a message while debouncing.\n\
-Note the priority of the interrupts sources.\n\
 \n";
 
 void print_instructions() {
+  write (STDERR_FILENO, instructions_msg, strlen(instructions_msg));
+}
 
-  //write (STDERR_FILENO, instructions_msg, strlen(instructions_msg));
-  printf(instructions_msg);
 
+//busy wait for the specified time
+void wait_ms(uint64_t ms) {
+  static const uint64_t ms_tick = RTC_FREQ/1000;
+  volatile uint64_t * mtime  = (uint64_t*) (CLINT_CTRL_ADDR + CLINT_MTIME);
+  uint64_t then = (ms_tick * ms) + *mtime;
+  while(*mtime<then);
 }
 
 void button_0_isr(void) __attribute__((interrupt));
 void button_0_isr(void) {
   // Toggle Red LED
-  	  
-  const char button_0_msg[] = "Button 0 was pressed. Toggle Red.\n";
-  write (STDOUT_FILENO, button_0_msg, strlen(button_0_msg));  
+  printf("Button 0 was pressed. Toggle Red.\n");
+  GPIO_REG(GPIO_OUTPUT_VAL) = GPIO_REG(GPIO_OUTPUT_VAL) ^ (0x1 << RED_LED_OFFSET);
+  wait_ms(500);
+  clic_enable_interrupt(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_0));
   GPIO_REG(GPIO_OUTPUT_VAL) = GPIO_REG(GPIO_OUTPUT_VAL) ^ (0x1 << RED_LED_OFFSET);
-  clic_clear_pending(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_0));
 }
 
 void button_0_setup(void) {
@@ -59,6 +62,36 @@ void button_0_setup(void) {
   clic_enable_interrupt(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_0));
 }
 
+void button_1_isr(void) __attribute__((interrupt));
+void button_1_isr(void) {
+  // Toggle Red LED
+  printf("Button 1 was pressed. Toggle Blue.\n");
+  GPIO_REG(GPIO_OUTPUT_VAL) = GPIO_REG(GPIO_OUTPUT_VAL) ^ (0x1 << BLUE_LED_OFFSET);
+  wait_ms(500);
+  clic_enable_interrupt(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_1));
+  GPIO_REG(GPIO_OUTPUT_VAL) = GPIO_REG(GPIO_OUTPUT_VAL) ^ (0x1 << BLUE_LED_OFFSET);
+}
+
+void button_1_setup(void) {
+  clic_install_handler(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_1), button_1_isr);
+  clic_enable_interrupt(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_1));
+}
+
+void button_2_isr(void) __attribute__((interrupt));
+void button_2_isr(void) {
+  // Toggle Red LED
+  printf("Button 2 was pressed. Toggle Green.\n");
+  GPIO_REG(GPIO_OUTPUT_VAL) = GPIO_REG(GPIO_OUTPUT_VAL) ^ (0x1 << GREEN_LED_OFFSET);
+  wait_ms(500);
+  clic_enable_interrupt(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_2));
+  GPIO_REG(GPIO_OUTPUT_VAL) = GPIO_REG(GPIO_OUTPUT_VAL) ^ (0x1 << GREEN_LED_OFFSET);
+}
+
+void button_2_setup(void) {
+  clic_install_handler(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_2), button_2_isr);
+  clic_enable_interrupt(&clic, (LOCALINTIDBASE + LOCAL_INT_BTN_2));
+}
+
 void config_gpio()  {
   // Configure LEDs as outputs.
   GPIO_REG(GPIO_INPUT_EN)    &= ~((0x1<< RED_LED_OFFSET) | (0x1<< GREEN_LED_OFFSET) | (0x1 << BLUE_LED_OFFSET)) ;
@@ -72,16 +105,19 @@ int main(int argc, char **argv)
   clear_csr(mie, IRQ_M_SOFT);
   clear_csr(mie, IRQ_M_TIMER);
 
-
+  //initialize clic registers and vector table
   clic_init(&clic, CLIC_HART0_ADDR, 
             (interrupt_function_ptr_t*)localISR,
             default_handler,
             CLIC_NUM_INTERRUPTS,
             CLIC_NUM_CONFIG_BITS);
 
-
+  //initialize gpio and buttons.
+  //each button registers an interrupt handler
   config_gpio();
   button_0_setup();
+  button_1_setup();
+  button_2_setup();
 
   // Enable all global interrupts
   set_csr(mstatus, MSTATUS_MIE);
-- 
cgit v1.2.1-18-gbd029