initial commit. working on tasking

1 files changed, 92 insertions, 0 deletions

diff --git a/arch/x86_64/hal/serial_com.c b/arch/x86_64/hal/serial_com.c
new file mode 100644
index 0000000..3967cd7
--- /dev/null
+++ b/arch/x86_64/hal/serial_com.c
@@ -0,0 +1,92 @@
+#include "serial_com.h"
+#include "port.h"
+#include "jove.h"
+#include "hal/obj.h"
+#include "init.h"
+#include "lib/printf.h"
+
+static int
+serial_com_recv(uint16_t port)
+{
+    return inb(SERIAL_COM_LSR(port)) & 1;
+}
+
+static char
+serial_com_getc(uint16_t port)
+{
+    while(serial_com_recv(port) == 0);
+    return inb(port);
+}
+
+static int
+serial_com_put_ready(uint16_t port)
+{
+    return inb(SERIAL_COM_LSR(port)) & 0x20;
+}
+
+static void 
+serial_com_putc(uint16_t port, char c)
+{
+    while(serial_com_put_ready(port) == 0);
+    outb(port, c);
+}
+
+int
+serial_com_init_port(
+        uint16_t port,
+        uint16_t baud_divisor)
+{
+    uint8_t div_low = (uint8_t)baud_divisor;
+    uint8_t div_high = (uint8_t)(baud_divisor >> 8);
+
+    outb(SERIAL_COM_IER(port), 0x00); // Disable all interrupts
+    outb(SERIAL_COM_LCR(port), 0x80); // Enable DLAB mode.
+    outb(SERIAL_COM_DLAB_BAUD_LO(port), div_low);
+    outb(SERIAL_COM_DLAB_BAUD_HI(port), div_high);
+    outb(SERIAL_COM_LCR(port), 0x03); // 8 bits, no parity, one stop bit.
+    outb(SERIAL_COM_FIFO(port), 0xC7); // Enable FIFO, clear them, 14 byte threshold.
+    outb(SERIAL_COM_MCR(port), 0x0B); // Enable IRQs, set RTS/DSR.
+ 
+    //Test to check if the serial port actually works.
+    outb(SERIAL_COM_MCR(port), 0x1E); // Set loopback mode.
+    outb(port, 0xAE); // Send test byte.
+    if(inb(port) != 0xAE) {
+        return 1;
+    }
+
+    //Set the port to normal operation mode.
+    //(no loopback, IRQs enabled, OUT#1 and OUT#2 enabled.)
+    outb(SERIAL_COM_MCR(port), 0x0F);
+    return 0;
+}
+
+void
+serial_com_init(void)
+{
+    if(serial_com_init_port(SERIAL_COM1, 3)) {
+        hcf();
+    }
+    
+    {
+        jove_owned_obj_t *com_obj = obj_take(objdir_getlocal(_rootdir_obj, ROOTDIR_SERIAL_COM_I));
+        obj_settype(com_obj, JOVE_OBJ_SERIAL_COM);
+        obj_setvalue(com_obj, SERIAL_COM1);
+        obj_release(com_obj);
+    }
+
+    kprintf("Initialized COM1 on port %X for obj %X\n", SERIAL_COM1, ROOTDIR_SERIAL_COM_I);
+}
+
+int
+serial_com_write(
+        jove_owned_obj_t *obj, 
+        const char *s, size_t len)
+{
+    if(obj->type != JOVE_OBJ_SERIAL_COM) {
+        reterr(EBADOBJ);
+    }
+    for(size_t i = 0; i < len; i++) {
+        serial_com_putc((uint16_t)obj->value, s[i]);
+    }
+    return len;
+}