1 /* $NetBSD: bcm2835_com_acpi.c,v 1.2 2021/08/08 18:55:12 jmcneill Exp $ */
2
3 /*
4 * Copyright (c) 2021 Jared McNeill <jmcneill@invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. The name of the author may not be used to endorse or promote products
13 * derived from this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: bcm2835_com_acpi.c,v 1.2 2021/08/08 18:55:12 jmcneill Exp $");
30
31 #include <sys/param.h>
32 #include <sys/device.h>
33 #include <sys/systm.h>
34 #include <sys/termios.h>
35
36 #include <dev/acpi/acpivar.h>
37 #include <dev/acpi/acpi_intr.h>
38
39 #include <dev/ic/comvar.h>
40
41 #include <arm/broadcom/bcm2835_mbox.h>
42 #include <evbarm/rpi/vcio.h>
43 #include <evbarm/rpi/vcprop.h>
44
45 static int bcmcom_acpi_match(device_t, cfdata_t , void *);
46 static void bcmcom_acpi_attach(device_t, device_t, void *);
47
48 static u_int bcmcom_acpi_get_clockrate(device_t);
49
50 struct vcmbox_clockrate_request {
51 struct vcprop_buffer_hdr vb_hdr;
52 struct vcprop_tag_clockrate vbt_clockrate;
53 struct vcprop_tag end;
54 } __packed;
55
56 CFATTACH_DECL_NEW(bcmcom_acpi, sizeof(struct com_softc), bcmcom_acpi_match,
57 bcmcom_acpi_attach, NULL, NULL);
58
59 static const struct device_compatible_entry compat_data[] = {
60 { .compat = "BCM2836", .value = COM_TYPE_BCMAUXUART },
61 DEVICE_COMPAT_EOL
62 };
63
64 static int
bcmcom_acpi_match(device_t parent,cfdata_t match,void * aux)65 bcmcom_acpi_match(device_t parent, cfdata_t match, void *aux)
66 {
67 struct acpi_attach_args *aa = aux;
68
69 return acpi_compatible_match(aa, compat_data);
70 }
71
72 static void
bcmcom_acpi_attach(device_t parent,device_t self,void * aux)73 bcmcom_acpi_attach(device_t parent, device_t self, void *aux)
74 {
75 struct com_softc *sc = device_private(self);
76 struct acpi_attach_args *aa = aux;
77 const struct device_compatible_entry *dce;
78 struct acpi_resources res;
79 struct acpi_mem *mem;
80 struct acpi_irq *irq;
81 bus_space_tag_t iot;
82 bus_space_handle_t ioh;
83 bus_addr_t base;
84 bus_size_t size;
85 ACPI_STATUS rv;
86 void *ih;
87
88 sc->sc_dev = self;
89
90 rv = acpi_resource_parse(sc->sc_dev, aa->aa_node->ad_handle, "_CRS",
91 &res, &acpi_resource_parse_ops_default);
92 if (ACPI_FAILURE(rv)) {
93 return;
94 }
95
96 mem = acpi_res_mem(&res, 0);
97 if (mem == NULL) {
98 aprint_error_dev(self, "couldn't find mem resource\n");
99 goto cleanup;
100 }
101
102 iot = aa->aa_memt;
103 base = mem->ar_base + 0x40;
104 size = mem->ar_length - 0x40;
105
106 irq = acpi_res_irq(&res, 0);
107 if (irq == NULL) {
108 aprint_error_dev(self, "couldn't find irq resource\n");
109 goto cleanup;
110 }
111
112 dce = acpi_compatible_lookup(aa, compat_data);
113 KASSERT(dce != NULL);
114
115 sc->sc_type = dce->value;
116
117 if (!com_is_console(iot, base, &ioh)) {
118 if (bus_space_map(iot, base, size, 0, &ioh)) {
119 aprint_error_dev(self, "can't map mem space\n");
120 goto cleanup;
121 }
122 }
123
124 com_init_regs_stride(&sc->sc_regs, iot, ioh, base, 2);
125
126 aprint_normal("%s", device_xname(self));
127
128 sc->sc_frequency = bcmcom_acpi_get_clockrate(self);
129
130 com_attach_subr(sc);
131
132 ih = acpi_intr_establish(self,
133 (uint64_t)(uintptr_t)aa->aa_node->ad_handle,
134 IPL_SERIAL, true, comintr, sc, device_xname(self));
135 if (ih == NULL) {
136 aprint_error_dev(self, "couldn't establish interrupt\n");
137 goto cleanup;
138 }
139
140 if (!pmf_device_register(self, NULL, com_resume))
141 aprint_error_dev(self, "couldn't establish a power handler\n");
142
143 cleanup:
144 acpi_resource_cleanup(&res);
145 }
146
147 static u_int
bcmcom_acpi_get_clockrate(device_t dev)148 bcmcom_acpi_get_clockrate(device_t dev)
149 {
150 struct vcmbox_clockrate_request vb;
151 uint32_t res;
152 int error;
153
154 VCPROP_INIT_REQUEST(vb);
155 VCPROP_INIT_TAG(vb.vbt_clockrate, VCPROPTAG_GET_CLOCKRATE);
156 vb.vbt_clockrate.id = htole32(VCPROP_CLK_CORE);
157 error = bcmmbox_request(BCMMBOX_CHANARM2VC, &vb, sizeof(vb), &res);
158 if (error != 0) {
159 aprint_error_dev(dev, "MBOX request failed: %d\n", error);
160 return 0;
161 }
162 if (!vcprop_buffer_success_p(&vb.vb_hdr) ||
163 !vcprop_tag_success_p(&vb.vbt_clockrate.tag)) {
164 return 0;
165 }
166
167 return le32toh(vb.vbt_clockrate.rate) * 2;
168 }
169