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
45static int	bcmcom_acpi_match(device_t, cfdata_t , void *);
46static void	bcmcom_acpi_attach(device_t, device_t, void *);
47
48static u_int	bcmcom_acpi_get_clockrate(device_t);
49
50struct 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
56CFATTACH_DECL_NEW(bcmcom_acpi, sizeof(struct com_softc), bcmcom_acpi_match,
57    bcmcom_acpi_attach, NULL, NULL);
58
59static const struct device_compatible_entry compat_data[] = {
60	{ .compat = "BCM2836",		.value = COM_TYPE_BCMAUXUART },
61	DEVICE_COMPAT_EOL
62};
63
64static int
65bcmcom_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
72static void
73bcmcom_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
143cleanup:
144	acpi_resource_cleanup(&res);
145}
146
147static u_int
148bcmcom_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