System Calls cleanup, multiple Processes and context switch

[cortex-from-scratch] / main.c

diff --git a/main.c b/main.c
index ac01416..4eb79f9 100644 (file)
--- a/main.c
+++ b/main.c
@@ -23,6 +23,7 @@
 #include <lib/stdio.h>
 #include <lib/string.h>
 #include <lib/tinyprintf.h>
+#include <lib/syscall.h>
 
 #include <drivers/uart.h>
 #include <drivers/led.h>
@@ -32,52 +33,18 @@
 //#include <drivers/mk450_joystick.h>
 #include <drivers/st7735s.h>
 
-#include <lib/syscall.h>
-
 
+/* Example of multitasking */
 process_t p1;
 process_t p2;
 
 uint32_t stackp1[500];
 uint32_t stackp2[500];
 
-extern int count;
-
-void switch_usermode() {
-
-       // user mode 
-       //asm volatile ("mov r0, 0x1" "\n\t" 
-       //"msr control, r0" "\n\t"
-       //"isb" "\n\t"); 
-
-       // system init call
-
-}
-
-void process1(void) {
-       
-       while(1) {
-               //uint32_t control = 0xFFFFFFFF;
-               printf("process 1\n");
-               //asm volatile("msr control, %0" "\n\t"
-               //             "dsb" : : "r" (control));
-               //printf("control: %x", control);       
-               //for(;;);
-               _block(100);
-               theos_switch(&p1, &p2);
-       }
+void process1(void);
+void process2(void);
 
-}
-void process2(void) {
-       while(1) {
-               printf("process 2\n");
-               _block(100);
-               theos_switch(&p2, &p1);
-       }
-       
-}
 
-int test_data_segment = 99;
 
 void main()
 {
@@ -116,38 +83,26 @@ void main()
        /* Real time clock */
        rtc_init();
 
-
-//     printf("press any key to start\n");
-//     asm volatile ("cpsid f"); // doesn't work in qemu
-
+       /* Initialize SVC handler for system calls*/
        syscall_init();
 
-       //int ret;
-       //ret = theos_test(0x1, 0x2, 0x3);
-       //ret = theos_uptime();
-
-       //printf("ret: %d\n", ret);
+       /* System call test */
+       int uptime = theos_uptime();
+       printf("UPTIME: %d\n", uptime);
 
-       int size_stack = sizeof(stackp1);
-       
-       p1.stackptr = ((unsigned int) stackp1) + size_stack - 0x1C;
-       p1.stackptr[6] = (uint32_t) process1;
-       p1.stackptr[7] = 0x01000000;
-       p2.stackptr = ((unsigned int) stackp2) + size_stack - 0x1C;
-       p2.stackptr[6] = (uint32_t) process2;
-       p2.stackptr[7] = 0x01000000;
-       
-       theos_init(&p1);
+       /* Multi processes test */
+//     int size_stack = sizeof(stackp1);
+//     p1.stackptr = ((unsigned int) stackp1) + size_stack - 0x1C;
+//     p1.stackptr[6] = (uint32_t) process1;
+//     p1.stackptr[7] = 0x01000000;
+//     p2.stackptr = ((unsigned int) stackp2) + size_stack - 0x1C;
+//     p2.stackptr[6] = (uint32_t) process2;
+//     p2.stackptr[7] = 0x01000000;
+//     theos_init(&p1);
 
        /* Cortex M* integrated systick, can be replaced
         * by the more accurate RTC. */
-       
-//     systick_init();
-
-       //      switch_usermode();      
-
-       //printf("without system call");        
-//     theos_test(0xA1, 0xA2);
+       //systick_init();
 
        /* Eeprom Driver
        eeprom_at24c_init();
@@ -169,7 +124,6 @@ void main()
        /* ADC Joystick module */
        // mk450_init();        
 
-
        /* Start up terminal */
        terminal();
        
@@ -178,3 +132,21 @@ void main()
 
        }
 }
+
+void process1(void) {
+       
+       while(1) {
+               printf("process 1\n");
+               _block(0xFFFFF);
+               theos_switch(&p1, &p2);
+       }
+
+}
+void process2(void) {
+       while(1) {
+               printf("process 2\n");
+               _block(0xFFFFF);
+               theos_switch(&p2, &p1);
+       }
+       
+}