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: stable/12/sys/dev/uart/uart_cpu_acpi.c 366942 2020-10-22 17:31:41Z mw $");
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
48 static struct acpi_uart_compat_data *
uart_cpu_acpi_scan(uint8_t interface_type)49 uart_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
73 int
uart_cpu_acpi_spcr(int devtype,struct uart_devinfo * di)74 uart_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
196 out:
197 acpi_unmap_table(spcr);
198 return (error);
199 }
200