Merged mcb30-realmode-redesign back to HEAD

src/arch/i386/firmware/pcbios/bios_console.c

@@ -0,0 +1,76 @@
+/* Etherboot routines for PCBIOS firmware.
+ *
+ * Body of routines taken from old pcbios.S
+ */
+
+#include "compiler.h"
+#include "realmode.h"
+#include "console.h"
+
+#define ZF ( 1 << 6 )
+
+/**************************************************************************
+bios_putchar - Print a character on console
+**************************************************************************/
+static void bios_putchar ( int character ) {
+	REAL_EXEC ( rm_console_putc,
+		    "sti\n\t"
+		    "movb $0x0e, %%ah\n\t"
+		    "movl $1, %%ebx\n\t"
+		    "int $0x10\n\t"
+		    "cli\n\t",
+		    1,
+		    OUT_CONSTRAINTS ( "=a" ( character ) ),
+		    IN_CONSTRAINTS ( "a" ( character ) ),
+		    CLOBBER ( "ebx", "ecx", "edx", "ebp", "esi", "edi" ) );
+
+	/* NOTE: %eax may be clobbered, so must be specified as an output
+	 * parameter, even though we don't then do anything with it.
+	 */
+}
+
+/**************************************************************************
+bios_getchar - Get a character from console
+**************************************************************************/
+static int bios_getchar ( void ) {
+	uint16_t character;
+	
+	REAL_EXEC ( rm_console_getc,
+		    "sti\n\t"
+		    "xorw %%ax, %%ax\n\t"
+		    "int $0x16\n\t"
+		    "cli\n\t",
+		    1,
+		    OUT_CONSTRAINTS ( "=a" ( character ) ),
+		    IN_CONSTRAINTS (),
+		    CLOBBER ( "ebx", "ecx", "edx", "ebp", "esi", "edi" ) );
+	
+	return ( character & 0xff );
+}
+
+/**************************************************************************
+bios_iskey - Check for keyboard interrupt
+**************************************************************************/
+static int bios_iskey ( void ) {
+	uint16_t flags;
+	
+	REAL_EXEC ( rm_console_ischar,
+		    "sti\n\t"
+		    "movb $1, %%ah\n\t"
+		    "int $0x16\n\t"
+		    "pushfw\n\t"
+		    "popw %%ax\n\t"
+		    "cli\n\t",
+		    1,
+		    OUT_CONSTRAINTS ( "=a" ( flags ) ),
+		    IN_CONSTRAINTS (),
+		    CLOBBER ( "ebx", "ecx", "edx", "ebp", "esi", "edi" ) );
+	
+	return ( ( flags & ZF ) == 0 );
+}
+
+static struct console_driver bios_console __console_driver = {
+	.putchar = bios_putchar,
+	.getchar = bios_getchar,
+	.iskey = bios_iskey,
+};