System Calls cleanup, multiple Processes and context switch

[cortex-from-scratch] / main.c

diff --git a/main.c b/main.c
index e87131a..4eb79f9 100644 (file)
--- a/main.c
+++ b/main.c
@@ -16,12 +16,14 @@
 
 #include <sys/robsys.h> 
 #include <sys/mmap.h>
+#include <sys/process.h>
 
 #include <lib/regfunc.h>
 #include <lib/pool.h>
 #include <lib/stdio.h>
 #include <lib/string.h>
 #include <lib/tinyprintf.h>
+#include <lib/syscall.h>
 
 #include <drivers/uart.h>
 #include <drivers/led.h>
@@ -32,43 +34,26 @@
 #include <drivers/st7735s.h>
 
 
-#include <lib/syscall.h>
-
-int test3(int i, int j) {
-
-       volatile uint32_t * sp = get_msp();
-       
-       /* asm volatile (
-       "tst lr, #4" "\n\t" 
-       "ite eq" "\n\t"
-       "mrseq %0, msp" "\n\t" 
-       "mrsne r0, psp" : "=r" (sp) ); */
-
-       for (int i = 0; (sp + i) < 0x20010000; i++) {
-               printf("ADDRESS: %p, VALUE: %x\n", (sp + i), *(sp + i));
-       }
+/* Example of multitasking */
+process_t p1;
+process_t p2;
 
-       for(;;);
-       return 0xCC;
-
-}
-int test2(int i, int j) {
+uint32_t stackp1[500];
+uint32_t stackp2[500];
 
-       int x = i * j;
-       test3(0x3A, 0x3B); 
-       
+void process1(void);
+void process2(void);
 
-}
-int test(int i, int j) {
 
-       test2(0x2A, 0x2B);
-       
-       return 0xAA;
-}
 
 void main()
 {
 
+       /* Load .data segment into SRAM */
+       extern uint32_t * data_lma, data_vma, data_end;
+       int size = (&data_end - &data_vma) * 4;
+       memcpy(&data_vma, &data_lma, size);
+
        /* Initialize the clock system, */
        clock_init();
 
@@ -81,11 +66,6 @@ void main()
        /* TFT screen */
        // tft_init();
        
-       /* Cortex M* integrated systick, can be replaced
-        * by the more accurate RTC.
-       systick_init();
-       */
-       
        /* Set up a very small libc library */
        init_printf(NULL, putc);
 
@@ -99,14 +79,30 @@ void main()
        /* On board LEDs*/
        led_init();
 
-       /* Real time clock */
-       //rtc_init();
 
-//     printf("press any key to start\n");
-//     asm volatile ("wfi");
+       /* Real time clock */
+       rtc_init();
 
+       /* Initialize SVC handler for system calls*/
        syscall_init();
-       theos_test(0xA1, 0xA2);
+
+       /* System call test */
+       int uptime = theos_uptime();
+       printf("UPTIME: %d\n", uptime);
+
+       /* 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();
 
        /* Eeprom Driver
        eeprom_at24c_init();
@@ -128,7 +124,6 @@ void main()
        /* ADC Joystick module */
        // mk450_init();        
 
-
        /* Start up terminal */
        terminal();
        
@@ -137,3 +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);
+       }
+       
+}