1 files changed, 134 insertions, 0 deletions
diff --git a/i386/i386at/immc.c b/i386/i386at/immc.c
new file mode 100644
index 0000000..00fc973
--- /dev/null
+++ b/i386/i386at/immc.c
@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 1995-1994 The University of Utah and
+ * the Computer Systems Laboratory at the University of Utah (CSL).
+ * All rights reserved.
+ *
+ * Permission to use, copy, modify and distribute this software is hereby
+ * granted provided that (1) source code retains these copyright, permission,
+ * and disclaimer notices, and (2) redistributions including binaries
+ * reproduce the notices in supporting documentation, and (3) all advertising
+ * materials mentioning features or use of this software display the following
+ * acknowledgement: ``This product includes software developed by the
+ * Computer Systems Laboratory at the University of Utah.''
+ *
+ * THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS
+ * IS" CONDITION.  THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF
+ * ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ *
+ * CSL requests users of this software to return to csl-dist@cs.utah.edu any
+ * improvements that they make and grant CSL redistribution rights.
+ *
+ *      Author: Bryan Ford, University of Utah CSL
+ */
+
+#if	ENABLE_IMMEDIATE_CONSOLE
+
+#include <device/cons.h>
+#include <mach/boolean.h>
+#include <i386/vm_param.h>
+#include <string.h>
+
+/* This is a special "feature" (read: kludge)
+   intended for use only for kernel debugging.
+   It enables an extremely simple console output mechanism
+   that sends text straight to CGA/EGA/VGA video memory.
+   It has the nice property of being functional right from the start,
+   so it can be used to debug things that happen very early
+   before any devices are initialized.  */
+
+boolean_t immediate_console_enable = TRUE;
+
+/*
+ * XXX we assume that pcs *always* have a console
+ */
+int
+immc_cnprobe(struct consdev *cp)
+{
+	int maj, unit, pri;
+
+	maj = 0;
+	unit = 0;
+	pri = CN_INTERNAL;
+
+	cp->cn_dev = makedev(maj, unit);
+	cp->cn_pri = pri;
+	return 0;
+}
+
+int
+immc_cninit(struct consdev *cp)
+{
+	return 0;
+}
+
+int immc_cnmaygetc(void)
+{
+	return -1;
+}
+
+int
+immc_cngetc(dev_t dev, int wait)
+{
+	if (wait) {
+		int c;
+		while ((c = immc_cnmaygetc()) < 0)
+			continue;
+		return c;
+	}
+	else
+		return immc_cnmaygetc();
+}
+
+int
+immc_cnputc(dev_t dev, int c)
+{
+	static int ofs = -1;
+
+	if (!immediate_console_enable)
+		return -1;
+	if (ofs < 0 || ofs >= 80)
+	{
+		ofs = 0;
+		immc_cnputc(dev, '\n');
+	}
+
+	if (c == '\n')
+	{
+		memmove((void *) phystokv(0xb8000),
+			(void *) phystokv(0xb8000+80*2), 80*2*24);
+		memset((void *) phystokv((0xb8000+80*2*24)), 0, 80*2);
+		ofs = 0;
+	}
+	else if (c == '\r')
+	{
+		ofs = 0;
+	}
+	else if (c == '\t')
+	{
+		ofs = (ofs & ~7) + 8;
+	}
+	else
+	{
+		volatile unsigned char *p;
+
+		if (ofs >= 80)
+		{
+			immc_cnputc(dev, '\r');
+			immc_cnputc(dev, '\n');
+		}
+
+		p = (void *) phystokv(0xb8000 + 80*2*24 + ofs*2);
+		p[0] = c;
+		p[1] = 0x0f;
+		ofs++;
+	}
+	return 0;
+}
+
+void
+immc_romputc(char c)
+{
+	immc_cnputc (0, c);
+}
+
+#endif /* ENABLE_IMMEDIATE_CONSOLE */