I use a legacy guest OS which sends the command 0xfd to the keyboard
controller during initialization. To get rid of the message
"qemu: unsupported keyboard cmd=0x%02x\n" I added support for
the pulse output bit commands.
Signed-off-by: Bernhard Kohl <bernhard.k...@nsn.com>
---
hw/pckbd.c | 23 ++++++++++++++++++++---
1 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/hw/pckbd.c b/hw/pckbd.c
index 7998aa6..554fbe4 100644
--- a/hw/pckbd.c
+++ b/hw/pckbd.c
@@ -50,7 +50,9 @@
#define KBD_CCMD_WRITE_MOUSE 0xD4 /* Write the following byte to
the mouse */
#define KBD_CCMD_DISABLE_A20 0xDD /* HP vectra only ? */
#define KBD_CCMD_ENABLE_A20 0xDF /* HP vectra only ? */
-#define KBD_CCMD_RESET 0xFE
+#define KBD_CCMD_PULSE_BITS_3_0 0xF0 /* Pulse bits 3-0 of the output
port P2. */
+#define KBD_CCMD_RESET 0xFE /* Pulse bit 0 of the output
port P2 = CPU reset. */
+#define KBD_CCMD_NO_OP 0xFF /* Pulse no bits of the output
port P2. */
/* Keyboard Commands */
#define KBD_CMD_SET_LEDS 0xED /* Set keyboard leds */
@@ -203,6 +205,21 @@ static void kbd_write_command(void *opaque,
uint32_t addr, uint32_t val)
#ifdef DEBUG_KBD
printf("kbd: write cmd=0x%02x\n", val);
#endif
+
+ /* Bits 3-0 of the output port P2 of the keyboard controller may be
pulsed
+ * low for approximately 6 micro seconds. Bits 3-0 of the
KBD_CCMD_PULSE
+ * command specify the output port bits to be pulsed.
+ * 0: Bit should be pulsed. 1: Bit should not be modified.
+ * The only useful version of this command is pulsing bit 0,
+ * which does a CPU reset.
+ */
+ if((val & KBD_CCMD_PULSE_BITS_3_0) == KBD_CCMD_PULSE_BITS_3_0) {
+ if(!(val & 1))
+ val = KBD_CCMD_RESET;
+ else
+ val = KBD_CCMD_NO_OP;
+ }
+
switch(val) {
case KBD_CCMD_READ_MODE:
kbd_queue(s, s->mode, 0);
@@ -265,8 +282,8 @@ static void kbd_write_command(void *opaque, uint32_t
addr, uint32_t val)
case KBD_CCMD_RESET:
qemu_system_reset_request();
break;
- case 0xff:
- /* ignore that - I don't know what is its use */
+ case KBD_CCMD_NO_OP:
+ /* ignore that */
break;
default:
fprintf(stderr, "qemu: unsupported keyboard cmd=0x%02x\n", val);
--
1.6.6.1
