Added syscalls.

CMakeLists.txt

@@ -7,10 +7,10 @@ project(hello)
 set(TARGET_LDSCRIPT "${CMAKE_SOURCE_DIR}/stx7105.ld")
 
 set(TARGET_SOURCES
-    "lib/printf/printf.c"
     "src/main.c"
     "src/stx7105_exc.c"
     "src/stx7105_utils.c"
+    "src/syscalls.c"
     "startup_stx7105.S"
 )
 

src/main.c

@@ -1,7 +1,6 @@
 #include <stdint.h>
 #include <stdio.h>
 
-#include "printf.h"
 #include "stx7105.h"
 #include "stx7105_utils.h"
 
@@ -16,8 +15,8 @@
 #define SYSTEM_CONFIG34 (0xFE001188U) /* PIO4 */
 #define SYSTEM_CONFIG7  (0xFE00111CU) /* RXSEL */
 
-#define MEMTEST_START 0x80010000
-#define MEMTEST_END   0x8FFE0000
+#define MEMTEST_START 0x82000000
+#define MEMTEST_END   0x8F000000
 
 void uart_init(void) {
     PIO4->CLR_PC0 = 1U; /* PC = 110, AFOUT, PP */
@@ -39,19 +38,19 @@ static void memory_test(void) {
         *(uint32_t *)i = i;
 
         if (i % 0x10000 == 0U) {
-            printf("Write to 0x%08x...\r\n", i);
+            printf("Write to 0x%08lx...\r\n", i);
         }
     }
 
     for (uint32_t i = MEMTEST_START; i < MEMTEST_END; i += 4) {
         if (*(uint32_t *)i != i) {
-            printf("Read back error at 0x%08x\r\n", i);
+            printf("Read back error at 0x%08lx\r\n", i);
 
             return;
         }
 
         if (i % 0x10000 == 0U) {
-            printf("Read from 0x%08x...\r\n", i);
+            printf("Read from 0x%08lx...\r\n", i);
         }
     }
 }
@@ -60,6 +59,9 @@ int main(void) {
     init_led(LED_RED_GPIO, LED_RED_PIN, 0U);
     init_led(LED_BLUE_GPIO, LED_BLUE_PIN, 0U);
 
+    setbuf(stdout,NULL);
+    setbuf(stderr,NULL);
+
     uart_init();
 
     printf("Hello world\r\n");
@@ -86,10 +88,3 @@ int main(void) {
 
     return 0;
 }
-
-void _putchar(char ch) {
-    while (CONSOLE_ASC->STA & 1 << 9U) {
-        // wait for TX FIFO slot.
-    }
-    CONSOLE_ASC->TX_BUF = ch;
-}

src/syscalls.c

@@ -0,0 +1,69 @@
+#include <sys/errno.h>
+#include <sys/stat.h>
+
+#include "stx7105.h"
+
+#define CONSOLE_ASC ASC2
+
+#define HEAP_SIZE 0x10000
+
+extern char     _end;
+static uint32_t s_heap_size = 0U;
+
+caddr_t _sbrk(int incr) {
+    char *heap_base = &_end;
+
+    caddr_t ret = heap_base + s_heap_size;
+
+    if (s_heap_size + incr >= HEAP_SIZE) {
+        return (void *)(-ENOMEM);
+    }
+
+    s_heap_size += incr;
+
+    return ret;
+}
+
+int _write(int file, char *ptr, int len) {
+    for (int i = 0; i < len; i++) {
+        while (CONSOLE_ASC->STA & 1 << 9U) {
+            // wait for TX FIFO slot.
+        }
+        CONSOLE_ASC->TX_BUF = ptr[i];
+    }
+    return len;
+}
+
+int _open(const char *name, int flags, int mode) {
+  return -1;
+}
+
+
+int _read(int file, char *ptr, int len) {
+    return 0;
+}
+
+int _lseek(int file, int ptr, int dir) {
+    return 0;
+}
+
+int _close(int file) {
+    return -1;
+}
+
+int _isatty(int file) {
+    return -1;
+}
+
+pid_t _getpid(void) {
+    return -1;
+}
+
+void _kill(int pid, int sig) {
+    return;
+}
+
+int _fstat(int file, struct stat *st) {
+    st->st_mode = S_IFCHR;
+    return 0;
+}