Index: stand/efi/include/efidevp.h
===================================================================
--- stand/efi/include/efidevp.h
+++ stand/efi/include/efidevp.h
@@ -141,6 +141,9 @@
   UINT32                          CID;
 } ACPI_EXTENDED_HID_DEVICE_PATH;
 
+#define ACPI_ADR_DP                         0x03
+/* ACPI_ADR_DEVICE_PATH not defined */
+
 //
 // EISA ID Macro
 // EISA ID Definition 32-bits
Index: stand/efi/loader/bootinfo.c
===================================================================
--- stand/efi/loader/bootinfo.c
+++ stand/efi/loader/bootinfo.c
@@ -68,10 +68,11 @@
 static int
 bi_getboothowto(char *kargs)
 {
-	const char *sw;
+	const char *sw, *tmp;
 	char *opts;
 	char *console;
-	int howto;
+	int howto, speed, port;
+	char buf[50];
 
 	howto = bootenv_flags();
 
@@ -81,6 +82,35 @@
 			howto |= RB_SERIAL;
 		if (strcmp(console, "nullconsole") == 0)
 			howto |= RB_MUTE;
+		if (strcmp(console, "efi") == 0) {
+			/*
+			 * If we found a com port and com speed, we need to tell
+			 * the kernel where the serial port is, and how
+			 * fast. Ideally, we'd get the port from ACPI, but that
+			 * isn't running in the loader. Do the next best thing
+			 * by allowing it to be set by a loader.conf variable,
+			 * either a EFI specific one, or the compatible
+			 * comconsole_port if not. PCI support is needed, but
+			 * for that we'd ideally refactor the
+			 * libi386/comconsole.c code to have identical behavior.
+			 */
+			tmp = getenv("efi_com_speed");
+			if (tmp != NULL) {
+				speed = strtol(tmp, NULL, 0);
+				tmp = getenv("efi_com_port");
+				if (tmp == NULL)
+					tmp = getenv("comconsole_port");
+				/* XXX fallback to EFI variable set in rc.d? */
+				if (tmp != NULL)
+					port = strtol(tmp, NULL, 0);
+				else
+					port = 0x3f8;
+				snprintf(buf, sizeof(buf), "io:%d,br:%d", port,
+				    speed);
+				env_setenv("hw.uart.console", EV_VOLATILE, buf,
+				    NULL, NULL);
+			}
+		}
 	}
 
 	/* Parse kargs */
Index: stand/efi/loader/main.c
===================================================================
--- stand/efi/loader/main.c
+++ stand/efi/loader/main.c
@@ -72,6 +72,8 @@
 EFI_GUID fdtdtb = FDT_TABLE_GUID;
 EFI_GUID inputid = SIMPLE_TEXT_INPUT_PROTOCOL;
 
+static bool uefi_boot_mgr;
+
 /*
  * Number of seconds to wait for a keystroke before exiting with failure
  * in the event no currdev is found. -2 means always break, -1 means
@@ -496,12 +498,67 @@
 	return (howto);
 }
 
+/*
+ * Parse ConOut (the list of consoles active) and see if we can find a
+ * serial port and/or a video port. It would be nice to also walk the
+ * ACPI name space to map the UID for the serial port to a port. The
+ * latter is especially hard.
+ */
+static int
+parse_uefi_con_out(void)
+{
+	int how, rv;
+	bool vid_seen = false, com_seen = false;
+	size_t sz;
+	char buf[4096], *ep;
+	EFI_DEVICE_PATH *node;
+	ACPI_HID_DEVICE_PATH  *acpi;
+	UART_DEVICE_PATH  *uart;
+
+	how = 0;
+	sz = sizeof(buf);
+	rv = efi_global_getenv("ConOut", buf, &sz);
+	if (rv != EFI_SUCCESS)
+		goto out;
+	ep = buf + sz;
+	node = (EFI_DEVICE_PATH *)buf;
+	while ((char *)node < ep) {
+		if (DevicePathType(node) == ACPI_DEVICE_PATH &&
+		    DevicePathSubType(node) == ACPI_DP) {
+			/* Check for Serial node */
+			acpi = (void *)node;
+			if (EISA_ID_TO_NUM(acpi->HID) == 0x501)
+				com_seen = true;
+		} else if (DevicePathType(node) == MESSAGING_DEVICE_PATH &&
+		    DevicePathSubType(node) == MSG_UART_DP) {
+			char bd[16];
+
+			uart = (void *)node;
+			snprintf(bd, sizeof(bd), "%d", uart->BaudRate);
+			setenv("efi_com_speed", bd, 1);
+			printf("Console speed is %d\n", uart->BaudRate);
+		} else if (DevicePathType(node) == ACPI_DEVICE_PATH &&
+		    DevicePathSubType(node) == ACPI_ADR_DP) {
+			/* Check for AcpiAdr() Node for video */
+			vid_seen = true;
+		}
+		node = NextDevicePathNode(node); /* Skip the end node */
+	}
+	if (vid_seen && com_seen)
+		how = RB_MULTIPLE | RB_SERIAL;
+	else if (com_seen)
+		how = RB_SERIAL;
+	else if (vid_seen)
+		how = RB_RESERVED1;
+out:
+	return (how);
+}
 
 EFI_STATUS
 main(int argc, CHAR16 *argv[])
 {
 	EFI_GUID *guid;
-	int howto, i;
+	int howto, i, uhowto;
 	UINTN k;
 	bool has_kbd;
 	char *s;
@@ -550,21 +607,37 @@
 
 	howto = parse_args(argc, argv, has_kbd);
 
-	bootenv_set(howto);
-
-	/*
-	 * XXX we need fallback to this stuff after looking at the ConIn, ConOut and ConErr variables
-	 */
-	if (howto & RB_MULTIPLE) {
-		if (howto & RB_SERIAL)
-			setenv("console", "comconsole efi" , 1);
-		else
-			setenv("console", "efi comconsole" , 1);
-	} else if (howto & RB_SERIAL) {
-		setenv("console", "comconsole" , 1);
-	} else
+	uhowto = parse_uefi_con_out();
+
+	printf("howto is %#x and uhowto is %#x\n", howto, uhowto);
+	if (uhowto == 0) {
+		/*
+		 * Couldn't figure it out from the ConOut env var, so fall back to
+		 * the command line stuff passed in.
+		 */
+		bootenv_set(howto);
+
+		/*
+		 * If there's no ConOut, then we have to set things, though it's
+		 * not clear how efi would work without it.
+		 */
+		if (howto & RB_MULTIPLE) {
+			if (howto & RB_SERIAL)
+				setenv("console", "comconsole efi" , 1);
+			else
+				setenv("console", "efi comconsole" , 1);
+		} else if (howto & RB_SERIAL) {
+			setenv("console", "comconsole" , 1);
+		} else
+			setenv("console", "efi", 1);
+	} else {
+		/*
+		 * ConOut found something, so blend the command line args with what we found.
+		 */
+		uhowto &= ~RB_RESERVED1;
+		bootenv_set(uhowto | (howto & ~(RB_MULTIPLE | RB_SERIAL)));
 		setenv("console", "efi", 1);
-
+	}
 	if (efi_copy_init()) {
 		printf("failed to allocate staging area\n");
 		return (EFI_BUFFER_TOO_SMALL);
@@ -651,7 +724,6 @@
 			return (EFI_NOT_FOUND);
 
 	efi_init_environment();
-	setenv("LINES", "24", 1);	/* optional */
 
 #if !defined(__arm__)
 	for (k = 0; k < ST->NumberOfTableEntries; k++) {