xref: /freebsd-14.2/sys/dev/uart/uart_cpu_acpi.c (revision f48bd752)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 
35 #include <machine/bus.h>
36 
37 #include <dev/pci/pcireg.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 static int
uart_cpu_acpi_init_devinfo(struct uart_devinfo * di,struct uart_class * class,ACPI_GENERIC_ADDRESS * addr)74 uart_cpu_acpi_init_devinfo(struct uart_devinfo *di, struct uart_class *class,
75     ACPI_GENERIC_ADDRESS *addr)
76 {
77 	/* Fill in some fixed details. */
78 	di->bas.chan = 0;
79 	di->bas.rclk = 0;
80 	di->databits = 8;
81 	di->stopbits = 1;
82 	di->parity = UART_PARITY_NONE;
83 	di->ops = uart_getops(class);
84 
85 	/* Fill in details from SPCR table. */
86 	switch (addr->SpaceId) {
87 	case 0:
88 		di->bas.bst = uart_bus_space_mem;
89 		break;
90 	case 1:
91 		di->bas.bst = uart_bus_space_io;
92 		break;
93 	default:
94 		printf("UART in unrecognized address space: %d!\n",
95 		    (int)addr->SpaceId);
96 		return (ENXIO);
97 	}
98 	switch (addr->AccessWidth) {
99 	case 0: /* EFI_ACPI_6_0_UNDEFINED */
100 		/* FALLTHROUGH */
101 	case 1: /* EFI_ACPI_6_0_BYTE */
102 		di->bas.regiowidth = 1;
103 		break;
104 	case 2: /* EFI_ACPI_6_0_WORD */
105 		di->bas.regiowidth = 2;
106 		break;
107 	case 3: /* EFI_ACPI_6_0_DWORD */
108 		di->bas.regiowidth = 4;
109 		break;
110 	case 4: /* EFI_ACPI_6_0_QWORD */
111 		di->bas.regiowidth = 8;
112 		break;
113 	default:
114 		printf("UART unsupported access width: %d!\n",
115 		    (int)addr->AccessWidth);
116 		return (ENXIO);
117 	}
118 	switch (addr->BitWidth) {
119 	case 0:
120 		/* FALLTHROUGH */
121 	case 8:
122 		di->bas.regshft = 0;
123 		break;
124 	case 16:
125 		di->bas.regshft = 1;
126 		break;
127 	case 32:
128 		di->bas.regshft = 2;
129 		break;
130 	case 64:
131 		di->bas.regshft = 3;
132 		break;
133 	default:
134 		printf("UART unsupported bit width: %d!\n",
135 		    (int)addr->BitWidth);
136 		return (ENXIO);
137 	}
138 
139 	return (0);
140 }
141 
142 int
uart_cpu_acpi_spcr(int devtype,struct uart_devinfo * di)143 uart_cpu_acpi_spcr(int devtype, struct uart_devinfo *di)
144 {
145 	vm_paddr_t spcr_physaddr;
146 	ACPI_TABLE_SPCR *spcr;
147 	struct acpi_uart_compat_data *cd;
148 	struct uart_class *class;
149 	int error = ENXIO;
150 
151 	/* SPCR only tells us about consoles. */
152 	if (devtype != UART_DEV_CONSOLE)
153 		return (error);
154 
155 	/* Look for the SPCR table. */
156 	spcr_physaddr = acpi_find_table(ACPI_SIG_SPCR);
157 	if (spcr_physaddr == 0)
158 		return (error);
159 	spcr = acpi_map_table(spcr_physaddr, ACPI_SIG_SPCR);
160 	if (spcr == NULL) {
161 		printf("Unable to map the SPCR table!\n");
162 		return (error);
163 	}
164 
165 	/* Search for information about this SPCR interface type. */
166 	cd = uart_cpu_acpi_scan(spcr->InterfaceType);
167 	if (cd == NULL)
168 		goto out;
169 	class = cd->cd_class;
170 
171 	error = uart_cpu_acpi_init_devinfo(di, class, &spcr->SerialPort);
172 	if (error != 0)
173 		goto out;
174 
175 	switch (spcr->BaudRate) {
176 	case 0:
177 		/* Special value; means "keep current value unchanged". */
178 		di->baudrate = 0;
179 		break;
180 	case 3:
181 		di->baudrate = 9600;
182 		break;
183 	case 4:
184 		di->baudrate = 19200;
185 		break;
186 	case 6:
187 		di->baudrate = 57600;
188 		break;
189 	case 7:
190 		di->baudrate = 115200;
191 		break;
192 	default:
193 		printf("SPCR has reserved BaudRate value: %d!\n",
194 		    (int)spcr->BaudRate);
195 		goto out;
196 	}
197 	if (spcr->PciVendorId != PCIV_INVALID &&
198 	    spcr->PciDeviceId != PCIV_INVALID) {
199 		di->pci_info.vendor = spcr->PciVendorId;
200 		di->pci_info.device = spcr->PciDeviceId;
201 	}
202 
203 	/* Apply device tweaks. */
204 	if ((cd->cd_quirks & UART_F_IGNORE_SPCR_REGSHFT) ==
205 	    UART_F_IGNORE_SPCR_REGSHFT) {
206 		di->bas.regshft = cd->cd_regshft;
207 	}
208 
209 	/* Create a bus space handle. */
210 	error = bus_space_map(di->bas.bst, spcr->SerialPort.Address,
211 	    uart_getrange(class), 0, &di->bas.bsh);
212 
213 out:
214 	acpi_unmap_table(spcr);
215 	return (error);
216 }
217