System Calls cleanup, multiple Processes and context switch

[cortex-from-scratch] / systick.c

diff --git a/systick.c b/systick.c
index 2c49820..f459512 100644 (file)
--- a/systick.c
+++ b/systick.c
@@ -21,31 +21,6 @@
 #include <lib/regfunc.h>
 #include <lib/tinyprintf.h>
 
-#define NUMB_TASKS 3
-
-int count;
-int next_task;
-int curr_task;
-uint32_t currentp;
-uint32_t nextp;
-
-//struct proces {
-//     int32_t nr;
-//     uint32_t *stack_ptr;
-//     uint32_t mask;
-//};
-//
-//struct proces p1, p2, p3;
-//
-//
-//     uint32_t oldpsp;
-//     uint32_t newpsp;
-//
-//uint32_t task0_stack[50];
-//uint32_t task1_stack[50];
-//uint32_t task2_stack[50];
-//uint32_t PSP_array[3];
-
 struct interrupt_frame {
 
         uint32_t r0; // N-32
@@ -61,25 +36,7 @@ struct interrupt_frame {
 //__attribute__ ((interrupt))
 void * systick_handler(/* struct interrupt_frame * frame */) {
 
-       //printf("Ticking...\n");
-       //printf("Current task: %d", curr_task);
-       //count++;
-
-
-
-
-       //switch(curr_task) {
-       //      case(0): next_task = 1; break;
-       //      case(1): next_task = 2; break;
-       //      case(2): next_task = 0; break;
-       //      default: next_task = 0; break;
-       //} 
-
-       //if (curr_task != next_task) {
-       
-               
-       
-       //} 
+       printf("Ticking...\n");
 
 }
 
@@ -114,10 +71,6 @@ uint32_t set_psp(uint32_t stackie) {
 
 void systick_init() {
 
-//     count = 0;
-//     curr_task = 0;
-//     next_task = 1;
-
        /* Every time the counter counts down to zero
         * a systick exception is invoked. Systick has
         * exception number 15. in the vector table  */
@@ -137,56 +90,4 @@ void systick_init() {
        rsetbit(STK_CTRL, 0);
        rsetbit(STK_CTRL, 1);
 
-//     extern void task0(void), task1(void), task2(void);
-//
-//     int size_stack = sizeof(task0_stack);
-//     
-//     p1.stack_ptr  = ((unsigned int) task0_stack) + size_stack - 0x1C;
-//     p1.stack_ptr[6] = (uint32_t) task0;
-//     p1.stack_ptr[7] = 0x01000000;
-//     p2.stack_ptr  = ((unsigned int) task0_stack) + size_stack - 0x1C;
-//     p2.stack_ptr[6] = (uint32_t) task1;
-//     p2.stack_ptr[7] = 0x01000000;
-//     p3.stack_ptr  = ((unsigned int) task0_stack) + size_stack - 0x1C;
-//     p3.stack_ptr[6] = (uint32_t) task2;
-//     p3.stack_ptr[7] = 0x01000000;
-//
-//     set_psp(p1.stack_ptr[-7]);
-//
-//     for(;;);        
-
-       /* Initialize processes */
-       //PSP_array[0] = ((unsigned int) task0_stack) + sizeof(task0_stack) - 32*4;
-       //HW_ADDR(PSP_array[0] + 0x18) = (unsigned long) task0;
-        //HW_ADDR(PSP_array[0] + 0x1C) = 0x01000000;   
-       //PSP_array[1] = ((unsigned int) task1_stack) + sizeof(task1_stack) - 32*4;
-       //HW_ADDR(PSP_array[1] + 0x18) = (unsigned long) task1;
-        //HW_ADDR(PSP_array[1] + 0x1C) = 0x01000000;   
-       //PSP_array[2] = ((unsigned int) task2_stack) + sizeof(task2_stack) - 32*4;
-       //HW_ADDR(PSP_array[2] + 0x18) = (unsigned long) task2;
-        //HW_ADDR(PSP_array[2] + 0x1C) = 0x01000000;   
-
-       //extern void pendsv_handler;
-
-       ivt_set_gate(14, pendsv_handler_c, 0);
-
-       //set_psp((PSP_array[curr_task] + 32*4 ));
-       
-       //int startpsp = PSP_array[curr_task] + 16*4;
-
-       //asm volatile ("msr psp, %0" : : "r" (startpsp));
-       
-       
-       //asm volatile ("mov r0, 0x3" "\n\t" 
-       //"msr control, r0" "\n\t"
-       //"isb" "\n\t"); 
-
-       //for(;;);
-
-       //set current PSP
-       //printf("0: %x\n", PSP_array[0]);
-       //printf("1: %x", PSP_array[0]);
-
-       //task0();
-
 }