Console functionality enhancement

common/cmdline.c

@@ -46,6 +46,9 @@ bool_cmd("hpet", opt_hpet);
 bool opt_fpu = false;
 bool_cmd("fpu", opt_fpu);
 
+bool opt_qemu_console = false;
+bool_cmd("qemu_console", opt_qemu_console);
+
 const char *kernel_cmdline;
 
 void __text_init cmdline_parse(const char *cmdline) {

common/console.c

@@ -35,12 +35,9 @@
 
 #include <smp/smp.h>
 
-#define QEMU_CONSOLE   0x0e9
-#define SERIAL_CONSOLE (com_ports[0])
-
 #define VPRINTK_BUF_SIZE 1024
 
-static console_callback_t console_callbacks[2];
+static console_callback_entry_t console_callbacks[2];
 static unsigned int num_console_callbacks;
 
 static void vprintk(const char *fmt, va_list args) {
@@ -56,8 +53,11 @@ static void vprintk(const char *fmt, va_list args) {
     if (rc > (int) sizeof(buf))
         panic("vprintk() buffer overflow\n");
 
-    for (i = 0; i < num_console_callbacks; i++)
-        console_callbacks[i](buf, rc);
+    for (i = 0; i < num_console_callbacks; i++) {
+        void *arg = console_callbacks[i].arg;
+
+        console_callbacks[i].cb(arg, buf, rc);
+    }
 
     spin_unlock(&lock);
 }
@@ -82,18 +82,25 @@ void AcpiOsPrintf(const char *Format, ...) {
 }
 #endif
 
-void putchar(int c) { putc(SERIAL_CONSOLE, c); }
+void serial_console_write(void *arg, const char *buf, size_t len) {
+    io_port_t port = (io_port_t) _ul(arg);
 
-void serial_console_write(const char *buf, size_t len) {
-    serial_write(SERIAL_CONSOLE, buf, len);
+    serial_write(port, buf, len);
 }
 
-void qemu_console_write(const char *buf, size_t len) { puts(QEMU_CONSOLE, buf, len); }
+void qemu_console_write(void *arg, const char *buf, size_t len) {
+    io_port_t port = (io_port_t) _ul(arg);
 
-void vga_console_write(const char *buf, size_t len) { vga_write(buf, len, VGA_WHITE); }
+    puts(port, buf, len);
+}
+
+void vga_console_write(void *vga_memory, const char *buf, size_t len) {
+    vga_write(vga_memory, buf, len, VGA_WHITE);
+}
 
-void register_console_callback(console_callback_t cb) {
-    console_callbacks[num_console_callbacks++] = cb;
+void register_console_callback(console_callback_t cb, void *arg) {
+    console_callbacks[num_console_callbacks].cb = cb;
+    console_callbacks[num_console_callbacks++].arg = arg;
 }
 
 void __noreturn panic(const char *fmt, ...) {

common/setup.c

@@ -71,13 +71,19 @@ char cpu_identifier[49];
 unsigned get_bsp_cpu_id(void) { return bsp_cpu_id; }
 void set_bsp_cpu_id(unsigned cpu_id) { bsp_cpu_id = cpu_id; }
 
+#define QEMU_CONSOLE_PORT 0x0e9
 static void __text_init init_console(void) {
     get_com_ports();
 
     uart_init(com_ports[0], DEFAULT_BAUD_SPEED);
-    register_console_callback(serial_console_write);
+    register_console_callback(serial_console_write, _ptr(com_ports[0]));
 
     printk("COM1: %x, COM2: %x\n", com_ports[0], com_ports[1]);
+
+    if (opt_qemu_console) {
+        register_console_callback(qemu_console_write, _ptr(QEMU_CONSOLE_PORT));
+        printk("Initialized QEMU console at port 0x%x", QEMU_CONSOLE_PORT);
+    }
 }
 
 static __always_inline void zero_bss(void) {
@@ -118,7 +124,7 @@ static void __text_init init_vga_console(void) {
 
     printk("Enabling VGA support\n");
     map_vga_area();
-    register_console_callback(vga_console_write);
+    register_console_callback(vga_console_write, paddr_to_virt_kern(VGA_START_ADDR));
 }
 
 void __noreturn __text_init kernel_start(uint32_t multiboot_magic,

drivers/vga.c

@@ -50,7 +50,7 @@ void vga_scroll_up(void) {
         write_vga_buffer(--scroll_screen);
 }
 
-void vga_write(const char *buf, size_t len, vga_color_t color) {
+void vga_write(void *vga_memory, const char *buf, size_t len, vga_color_t color) {
     static int screen = 0, row = 0, col = 0;
 
     for (unsigned int i = 0; i < len; i++) {
@@ -77,7 +77,7 @@ void vga_write(const char *buf, size_t len, vga_color_t color) {
     }
 
     scroll_screen = screen;
-    write_vga_buffer(screen);
+    memcpy(vga_memory, vga_buffer[screen], sizeof(vga_buffer[screen]));
 }
 
 void map_vga_area(void) {

include/cmdline.h

@@ -63,6 +63,7 @@ extern bool opt_pit;
 extern bool opt_apic_timer;
 extern bool opt_hpet;
 extern bool opt_fpu;
+extern bool opt_qemu_console;
 extern const char *kernel_cmdline;
 
 extern void cmdline_parse(const char *cmdline);

include/console.h

@@ -27,7 +27,13 @@
 
 #include <ktf.h>
 
-typedef void (*console_callback_t)(const char *buf, size_t len);
+typedef void (*console_callback_t)(void *arg, const char *buf, size_t len);
+
+struct console_callback_entry {
+    console_callback_t cb;
+    void *arg;
+};
+typedef struct console_callback_entry console_callback_entry_t;
 
 extern void printk(const char *fmt, ...);
 
@@ -37,13 +43,11 @@ extern void printk(const char *fmt, ...);
             printk("%s (%s.%d): " fmt, __FILE__, __func__, __LINE__, ##__VA_ARGS__);     \
     } while (0)
 
-extern void putchar(int c);
-
-extern void serial_console_write(const char *buf, size_t len);
-extern void qemu_console_write(const char *buf, size_t len);
-extern void vga_console_write(const char *buf, size_t len);
+extern void serial_console_write(void *arg, const char *buf, size_t len);
+extern void qemu_console_write(void *arg, const char *buf, size_t len);
+extern void vga_console_write(void *arg, const char *buf, size_t len);
 
-extern void register_console_callback(console_callback_t func);
+extern void register_console_callback(console_callback_t func, void *arg);
 
 extern void panic(const char *fmt, ...);
 

include/drivers/vga.h

@@ -58,7 +58,7 @@ typedef enum vga_color vga_color_t;
 extern void vga_scroll_up(void);
 extern void vga_scroll_down(void);
 
-extern void vga_write(const char *buf, size_t len, vga_color_t color);
+extern void vga_write(void *vga_memory, const char *buf, size_t len, vga_color_t color);
 
 extern void map_vga_area(void);
 #endif /* KTF_DRV_VGA_H */