Make sure cursor is initialized

* i386/i386at/kd.c (kd_xga_init): Add start, stop variables, read them
from CRT registers, make sure the cursor is enabled and is not reduced
to 0, and write them back to CRT registers.
* i386/i386at/kd.h (C_START, C_STOP): New macros.

2 files changed, 21 insertions, 0 deletions

diff --git a/i386/i386at/kd.c b/i386/i386at/kd.c
index 3c66cc5..f70175c 100644
--- a/i386/i386at/kd.c
+++ b/i386/i386at/kd.c
@@ -2498,6 +2498,7 @@ kd_xga_init(void)
 {
 	csrpos_t	xga_getpos();
 	unsigned char	screen;
+	unsigned char	start, stop;
 
 	outb(CMOS_ADDR, CMOS_EB);
 	screen = inb(CMOS_DATA) & CM_SCRMSK;
@@ -2552,6 +2553,24 @@ kd_xga_init(void)
 		printf("kd: unknown screen type, defaulting to EGA\n");
 	}
 
+	outb(kd_index_reg, C_START);
+	start = inb(kd_io_reg);
+	/* Make sure cursor is enabled */
+	start &= ~0x20;
+	outb(kd_io_reg, start);
+	outb(kd_index_reg, C_STOP);
+	stop = inb(kd_io_reg);
+
+	if (!start && !stop)
+	{
+		/* Some firmware seem not to be initializing the cursor size
+		 * any more...  Try using standard values.  */
+		outb(kd_index_reg, C_START);
+		outb(kd_io_reg, 14);
+		outb(kd_index_reg, C_STOP);
+		outb(kd_io_reg, 15);
+	}
+
 	kd_setpos(xga_getpos());
 }
 
diff --git a/i386/i386at/kd.h b/i386/i386at/kd.h
index 0907e23..6c869d6 100644
--- a/i386/i386at/kd.h
+++ b/i386/i386at/kd.h
@@ -113,6 +113,8 @@ WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 /*
  * Commands sent to graphics adapter.
  */
+#define C_START 	0x0a		/* return cursor line start */
+#define C_STOP 		0x0b		/* return cursor line stop */
 #define C_LOW 		0x0f		/* return low byte of cursor addr */
 #define C_HIGH 		0x0e		/* high byte */