1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2016 The FreeBSD Foundation
5 * Copyright (c) 2019 Colin Percival
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/bus.h>
36
37#include <machine/bus.h>
38
39#include <dev/uart/uart.h>
40#include <dev/uart/uart_bus.h>
41#include <dev/uart/uart_cpu.h>
42#include <dev/uart/uart_cpu_acpi.h>
43
44#include <contrib/dev/acpica/include/acpi.h>
45#include <contrib/dev/acpica/include/accommon.h>
46#include <contrib/dev/acpica/include/actables.h>
47
48static struct acpi_uart_compat_data *
49uart_cpu_acpi_scan(uint8_t interface_type)
50{
51	struct acpi_uart_compat_data **cd, *curcd;
52	int i;
53
54	SET_FOREACH(cd, uart_acpi_class_and_device_set) {
55		curcd = *cd;
56		for (i = 0; curcd[i].cd_hid != NULL; i++) {
57			if (curcd[i].cd_port_subtype == interface_type)
58				return (&curcd[i]);
59		}
60	}
61
62	SET_FOREACH(cd, uart_acpi_class_set) {
63		curcd = *cd;
64		for (i = 0; curcd[i].cd_hid != NULL; i++) {
65			if (curcd[i].cd_port_subtype == interface_type)
66				return (&curcd[i]);
67		}
68	}
69
70	return (NULL);
71}
72
73int
74uart_cpu_acpi_spcr(int devtype, struct uart_devinfo *di)
75{
76	vm_paddr_t spcr_physaddr;
77	ACPI_TABLE_SPCR *spcr;
78	struct acpi_uart_compat_data *cd;
79	struct uart_class *class;
80	int error = ENXIO;
81
82	/* SPCR only tells us about consoles. */
83	if (devtype != UART_DEV_CONSOLE)
84		return (error);
85
86	/* Look for the SPCR table. */
87	spcr_physaddr = acpi_find_table(ACPI_SIG_SPCR);
88	if (spcr_physaddr == 0)
89		return (error);
90	spcr = acpi_map_table(spcr_physaddr, ACPI_SIG_SPCR);
91	if (spcr == NULL) {
92		printf("Unable to map the SPCR table!\n");
93		return (error);
94	}
95
96	/* Search for information about this SPCR interface type. */
97	cd = uart_cpu_acpi_scan(spcr->InterfaceType);
98	if (cd == NULL)
99		goto out;
100	class = cd->cd_class;
101
102	/* Fill in some fixed details. */
103	di->bas.chan = 0;
104	di->bas.rclk = 0;
105	di->databits = 8;
106	di->stopbits = 1;
107	di->parity = UART_PARITY_NONE;
108	di->ops = uart_getops(class);
109
110	/* Fill in details from SPCR table. */
111	switch (spcr->SerialPort.SpaceId) {
112	case 0:
113		di->bas.bst = uart_bus_space_mem;
114		break;
115	case 1:
116		di->bas.bst = uart_bus_space_io;
117		break;
118	default:
119		printf("UART in unrecognized address space: %d!\n",
120		    (int)spcr->SerialPort.SpaceId);
121		goto out;
122	}
123	switch (spcr->SerialPort.AccessWidth) {
124	case 0: /* EFI_ACPI_6_0_UNDEFINED */
125		/* FALLTHROUGH */
126	case 1: /* EFI_ACPI_6_0_BYTE */
127		di->bas.regiowidth = 1;
128		break;
129	case 2: /* EFI_ACPI_6_0_WORD */
130		di->bas.regiowidth = 2;
131		break;
132	case 3: /* EFI_ACPI_6_0_DWORD */
133		di->bas.regiowidth = 4;
134		break;
135	case 4: /* EFI_ACPI_6_0_QWORD */
136		di->bas.regiowidth = 8;
137		break;
138	default:
139		printf("UART unsupported access width: %d!\n",
140		    (int)spcr->SerialPort.AccessWidth);
141		goto out;
142	}
143	switch (spcr->SerialPort.BitWidth) {
144	case 0:
145		/* FALLTHROUGH */
146	case 8:
147		di->bas.regshft = 0;
148		break;
149	case 16:
150		di->bas.regshft = 1;
151		break;
152	case 32:
153		di->bas.regshft = 2;
154		break;
155	case 64:
156		di->bas.regshft = 3;
157		break;
158	default:
159		printf("UART unsupported bit width: %d!\n",
160		    (int)spcr->SerialPort.BitWidth);
161		goto out;
162	}
163	switch (spcr->BaudRate) {
164	case 0:
165		/* Special value; means "keep current value unchanged". */
166		di->baudrate = 0;
167		break;
168	case 3:
169		di->baudrate = 9600;
170		break;
171	case 4:
172		di->baudrate = 19200;
173		break;
174	case 6:
175		di->baudrate = 57600;
176		break;
177	case 7:
178		di->baudrate = 115200;
179		break;
180	default:
181		printf("SPCR has reserved BaudRate value: %d!\n",
182		    (int)spcr->BaudRate);
183		goto out;
184	}
185
186	/* Apply device tweaks. */
187	if ((cd->cd_quirks & UART_F_IGNORE_SPCR_REGSHFT) ==
188	    UART_F_IGNORE_SPCR_REGSHFT) {
189		di->bas.regshft = cd->cd_regshft;
190	}
191
192	/* Create a bus space handle. */
193	error = bus_space_map(di->bas.bst, spcr->SerialPort.Address,
194	    uart_getrange(class), 0, &di->bas.bsh);
195
196out:
197	acpi_unmap_table(spcr);
198	return (error);
199}
200