1 files changed, 167 insertions, 0 deletions

diff --git a/sys/dev/uart/uart_cpu_acpi.c b/sys/dev/uart/uart_cpu_acpi.c
new file mode 100644
index 000000000000..e91bdb22b779
--- /dev/null
+++ b/sys/dev/uart/uart_cpu_acpi.c
@@ -0,0 +1,167 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2016 The FreeBSD Foundation
+ * Copyright (c) 2019 Colin Percival
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+
+#include <machine/bus.h>
+
+#include <dev/uart/uart.h>
+#include <dev/uart/uart_bus.h>
+#include <dev/uart/uart_cpu.h>
+#include <dev/uart/uart_cpu_acpi.h>
+
+#include <contrib/dev/acpica/include/acpi.h>
+#include <contrib/dev/acpica/include/accommon.h>
+#include <contrib/dev/acpica/include/actables.h>
+
+extern bus_space_tag_t uart_bus_space_io;
+extern bus_space_tag_t uart_bus_space_mem;
+
+static struct acpi_uart_compat_data *
+uart_cpu_acpi_scan(uint8_t interface_type)
+{
+	struct acpi_uart_compat_data **cd, *curcd;
+	int i;
+
+	SET_FOREACH(cd, uart_acpi_class_and_device_set) {
+		curcd = *cd;
+		for (i = 0; curcd[i].cd_hid != NULL; i++) {
+			if (curcd[i].cd_port_subtype == interface_type)
+				return (&curcd[i]);
+		}
+	}
+
+	SET_FOREACH(cd, uart_acpi_class_set) {
+		curcd = *cd;
+		for (i = 0; curcd[i].cd_hid != NULL; i++) {
+			if (curcd[i].cd_port_subtype == interface_type)
+				return (&curcd[i]);
+		}
+	}
+
+	return (NULL);
+}
+
+int
+uart_cpu_acpi_spcr(int devtype, struct uart_devinfo *di)
+{
+	vm_paddr_t spcr_physaddr;
+	ACPI_TABLE_SPCR *spcr;
+	struct acpi_uart_compat_data *cd;
+	struct uart_class *class;
+	int error = ENXIO;
+
+	/* SPCR only tells us about consoles. */
+	if (devtype != UART_DEV_CONSOLE)
+		return (error);
+
+	/* Look for the SPCR table. */
+	spcr_physaddr = acpi_find_table(ACPI_SIG_SPCR);
+	if (spcr_physaddr == 0)
+		return (error);
+	spcr = acpi_map_table(spcr_physaddr, ACPI_SIG_SPCR);
+	if (spcr == NULL) {
+		printf("Unable to map the SPCR table!\n");
+		return (error);
+	}
+
+	/* Search for information about this SPCR interface type. */
+	cd = uart_cpu_acpi_scan(spcr->InterfaceType);
+	if (cd == NULL)
+		goto out;
+	class = cd->cd_class;
+
+	/* Fill in some fixed details. */
+	di->bas.chan = 0;
+	di->bas.rclk = 0;
+	di->databits = 8;
+	di->stopbits = 1;
+	di->parity = UART_PARITY_NONE;
+	di->ops = uart_getops(class);
+
+	/* Fill in details from SPCR table. */
+	switch (spcr->SerialPort.SpaceId) {
+	case 0:
+		di->bas.bst = uart_bus_space_mem;
+		break;
+	case 1:
+		di->bas.bst = uart_bus_space_io;
+		break;
+	default:
+		printf("UART in unrecognized address space: %d!\n",
+		    (int)spcr->SerialPort.SpaceId);
+		goto out;
+	}
+	if (spcr->SerialPort.AccessWidth == 0)
+		di->bas.regshft = 0;
+	else
+		di->bas.regshft = spcr->SerialPort.AccessWidth - 1;
+	di->bas.regiowidth = spcr->SerialPort.BitWidth / 8;
+	switch (spcr->BaudRate) {
+	case 0:
+		/* Special value; means "keep current value unchanged". */
+		di->baudrate = 0;
+		break;
+	case 3:
+		di->baudrate = 9600;
+		break;
+	case 4:
+		di->baudrate = 19200;
+		break;
+	case 6:
+		di->baudrate = 57600;
+		break;
+	case 7:
+		di->baudrate = 115200;
+		break;
+	default:
+		printf("SPCR has reserved BaudRate value: %d!\n",
+		    (int)spcr->BaudRate);
+		goto out;
+	}
+
+	/* Apply device tweaks. */
+	if ((cd->cd_quirks & UART_F_IGNORE_SPCR_REGSHFT) ==
+	    UART_F_IGNORE_SPCR_REGSHFT) {
+		di->bas.regshft = cd->cd_regshft;
+	}
+
+	/* Create a bus space handle. */
+	error = bus_space_map(di->bas.bst, spcr->SerialPort.Address,
+	    uart_getrange(class), 0, &di->bas.bsh);
+
+out:
+	acpi_unmap_table(spcr);
+	return (error);
+}