5650 - support a second OS: soso

https://github.com/ozkl/soso

+ Much smaller than Linux; builds instantly
+ Supports graphics
- No network support
- Doesn't work on a cloud server (yet?)

1 files changed, 97 insertions, 0 deletions

diff --git a/kernel.soso/serial.c b/kernel.soso/serial.c
new file mode 100644
index 00000000..6615d845
--- /dev/null
+++ b/kernel.soso/serial.c
@@ -0,0 +1,97 @@
+#include "common.h"
+#include "serial.h"
+
+#define PORT 0x3f8   //COM1
+
+void initializeSerial()
+{
+   outb(PORT + 1, 0x00);    // Disable all interrupts
+   outb(PORT + 3, 0x80);    // Enable DLAB (set baud rate divisor)
+   outb(PORT + 0, 0x03);    // Set divisor to 3 (lo byte) 38400 baud
+   outb(PORT + 1, 0x00);    //                  (hi byte)
+   outb(PORT + 3, 0x03);    // 8 bits, no parity, one stop bit
+   outb(PORT + 2, 0xC7);    // Enable FIFO, clear them, with 14-byte threshold
+   outb(PORT + 4, 0x0B);    // IRQs enabled, RTS/DSR set
+}
+
+int serialReceived()
+{
+   return inb(PORT + 5) & 1;
+}
+
+char readSerial()
+{
+   while (serialReceived() == 0);
+
+   return inb(PORT);
+}
+
+int isTransmitEmpty()
+{
+   return inb(PORT + 5) & 0x20;
+}
+
+void writeSerial(char a)
+{
+   while (isTransmitEmpty() == 0);
+
+   outb(PORT,a);
+}
+
+void Serial_PrintF(const char *format, ...)
+{
+  char **arg = (char **) &format;
+  char c;
+  char buf[20];
+
+  //arg++;
+  __builtin_va_list vl;
+  __builtin_va_start(vl, format);
+
+  while ((c = *format++) != 0)
+    {
+      if (c != '%')
+        writeSerial(c);
+      else
+        {
+          char *p;
+
+          c = *format++;
+          switch (c)
+            {
+            case 'x':
+               buf[0] = '0';
+               buf[1] = 'x';
+               //itoa (buf + 2, c, *((int *) arg++));
+               itoa (buf + 2, c, __builtin_va_arg(vl, int));
+               p = buf;
+               goto string;
+               break;
+            case 'd':
+            case 'u':
+              //itoa (buf, c, *((int *) arg++));
+              itoa (buf, c, __builtin_va_arg(vl, int));
+              p = buf;
+              goto string;
+              break;
+
+            case 's':
+              //p = *arg++;
+              p = __builtin_va_arg(vl, char*);
+              if (! p)
+                p = "(null)";
+
+            string:
+              while (*p)
+                writeSerial(*p++);
+              break;
+
+            default:
+              //writeSerial(*((int *) arg++));
+              writeSerial(__builtin_va_arg(vl, int));
+              break;
+            }
+        }
+    }
+  __builtin_va_end(vl);
+}