xref: /freebsd/sys/dev/uart/uart_cpu_acpi.c (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)
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/pci/pcireg.h>
40 
41 #include <dev/uart/uart.h>
42 #include <dev/uart/uart_bus.h>
43 #include <dev/uart/uart_cpu.h>
44 #include <dev/uart/uart_cpu_acpi.h>
45 
46 #include <contrib/dev/acpica/include/acpi.h>
47 #include <contrib/dev/acpica/include/accommon.h>
48 #include <contrib/dev/acpica/include/actables.h>
49 
50 static struct acpi_uart_compat_data *
51 uart_cpu_acpi_scan(uint8_t interface_type)
52 {
53 	struct acpi_uart_compat_data **cd, *curcd;
54 	int i;
55 
56 	SET_FOREACH(cd, uart_acpi_class_and_device_set) {
57 		curcd = *cd;
58 		for (i = 0; curcd[i].cd_hid != NULL; i++) {
59 			if (curcd[i].cd_port_subtype == interface_type)
60 				return (&curcd[i]);
61 		}
62 	}
63 
64 	SET_FOREACH(cd, uart_acpi_class_set) {
65 		curcd = *cd;
66 		for (i = 0; curcd[i].cd_hid != NULL; i++) {
67 			if (curcd[i].cd_port_subtype == interface_type)
68 				return (&curcd[i]);
69 		}
70 	}
71 
72 	return (NULL);
73 }
74 
75 int
76 uart_cpu_acpi_spcr(int devtype, struct uart_devinfo *di)
77 {
78 	vm_paddr_t spcr_physaddr;
79 	ACPI_TABLE_SPCR *spcr;
80 	struct acpi_uart_compat_data *cd;
81 	struct uart_class *class;
82 	int error = ENXIO;
83 
84 	/* SPCR only tells us about consoles. */
85 	if (devtype != UART_DEV_CONSOLE)
86 		return (error);
87 
88 	/* Look for the SPCR table. */
89 	spcr_physaddr = acpi_find_table(ACPI_SIG_SPCR);
90 	if (spcr_physaddr == 0)
91 		return (error);
92 	spcr = acpi_map_table(spcr_physaddr, ACPI_SIG_SPCR);
93 	if (spcr == NULL) {
94 		printf("Unable to map the SPCR table!\n");
95 		return (error);
96 	}
97 
98 	/* Search for information about this SPCR interface type. */
99 	cd = uart_cpu_acpi_scan(spcr->InterfaceType);
100 	if (cd == NULL)
101 		goto out;
102 	class = cd->cd_class;
103 
104 	/* Fill in some fixed details. */
105 	di->bas.chan = 0;
106 	di->bas.rclk = 0;
107 	di->databits = 8;
108 	di->stopbits = 1;
109 	di->parity = UART_PARITY_NONE;
110 	di->ops = uart_getops(class);
111 
112 	/* Fill in details from SPCR table. */
113 	switch (spcr->SerialPort.SpaceId) {
114 	case 0:
115 		di->bas.bst = uart_bus_space_mem;
116 		break;
117 	case 1:
118 		di->bas.bst = uart_bus_space_io;
119 		break;
120 	default:
121 		printf("UART in unrecognized address space: %d!\n",
122 		    (int)spcr->SerialPort.SpaceId);
123 		goto out;
124 	}
125 	switch (spcr->SerialPort.AccessWidth) {
126 	case 0: /* EFI_ACPI_6_0_UNDEFINED */
127 		/* FALLTHROUGH */
128 	case 1: /* EFI_ACPI_6_0_BYTE */
129 		di->bas.regiowidth = 1;
130 		break;
131 	case 2: /* EFI_ACPI_6_0_WORD */
132 		di->bas.regiowidth = 2;
133 		break;
134 	case 3: /* EFI_ACPI_6_0_DWORD */
135 		di->bas.regiowidth = 4;
136 		break;
137 	case 4: /* EFI_ACPI_6_0_QWORD */
138 		di->bas.regiowidth = 8;
139 		break;
140 	default:
141 		printf("UART unsupported access width: %d!\n",
142 		    (int)spcr->SerialPort.AccessWidth);
143 		goto out;
144 	}
145 	switch (spcr->SerialPort.BitWidth) {
146 	case 0:
147 		/* FALLTHROUGH */
148 	case 8:
149 		di->bas.regshft = 0;
150 		break;
151 	case 16:
152 		di->bas.regshft = 1;
153 		break;
154 	case 32:
155 		di->bas.regshft = 2;
156 		break;
157 	case 64:
158 		di->bas.regshft = 3;
159 		break;
160 	default:
161 		printf("UART unsupported bit width: %d!\n",
162 		    (int)spcr->SerialPort.BitWidth);
163 		goto out;
164 	}
165 	switch (spcr->BaudRate) {
166 	case 0:
167 		/* Special value; means "keep current value unchanged". */
168 		di->baudrate = 0;
169 		break;
170 	case 3:
171 		di->baudrate = 9600;
172 		break;
173 	case 4:
174 		di->baudrate = 19200;
175 		break;
176 	case 6:
177 		di->baudrate = 57600;
178 		break;
179 	case 7:
180 		di->baudrate = 115200;
181 		break;
182 	default:
183 		printf("SPCR has reserved BaudRate value: %d!\n",
184 		    (int)spcr->BaudRate);
185 		goto out;
186 	}
187 	if (spcr->PciVendorId != PCIV_INVALID &&
188 	    spcr->PciDeviceId != PCIV_INVALID) {
189 		di->pci_info.vendor = spcr->PciVendorId;
190 		di->pci_info.device = spcr->PciDeviceId;
191 	}
192 
193 	/* Apply device tweaks. */
194 	if ((cd->cd_quirks & UART_F_IGNORE_SPCR_REGSHFT) ==
195 	    UART_F_IGNORE_SPCR_REGSHFT) {
196 		di->bas.regshft = cd->cd_regshft;
197 	}
198 
199 	/* Create a bus space handle. */
200 	error = bus_space_map(di->bas.bst, spcr->SerialPort.Address,
201 	    uart_getrange(class), 0, &di->bas.bsh);
202 
203 out:
204 	acpi_unmap_table(spcr);
205 	return (error);
206 }
207