1 /* $NetBSD: bcm2835_com.c,v 1.9 2023/12/11 12:53:08 mlelstv Exp $ */
2
3 /*-
4 * Copyright (c) 2017 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. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: bcm2835_com.c,v 1.9 2023/12/11 12:53:08 mlelstv Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/intr.h>
36 #include <sys/systm.h>
37 #include <sys/termios.h>
38
39 #include <arm/broadcom/bcm2835reg.h>
40 #include <arm/broadcom/bcm2835var.h>
41 #include <arm/broadcom/bcm2835_intr.h>
42
43 #include <dev/fdt/fdtvar.h>
44
45 #include <dev/ic/comvar.h>
46
47 static int bcm_com_match(device_t, cfdata_t, void *);
48 static void bcm_com_attach(device_t, device_t, void *);
49
50 CFATTACH_DECL_NEW(bcmcom, sizeof(struct com_softc),
51 bcm_com_match, bcm_com_attach, NULL, NULL);
52
53 static const struct device_compatible_entry compat_data[] = {
54 { .compat = "brcm,bcm2835-aux-uart" },
55 DEVICE_COMPAT_EOL
56 };
57
58 static int
bcm_com_match(device_t parent,cfdata_t cf,void * aux)59 bcm_com_match(device_t parent, cfdata_t cf, void *aux)
60 {
61 struct fdt_attach_args * const faa = aux;
62
63 return of_compatible_match(faa->faa_phandle, compat_data);
64 }
65
66 static void
bcm_com_attach(device_t parent,device_t self,void * aux)67 bcm_com_attach(device_t parent, device_t self, void *aux)
68 {
69 struct com_softc * const sc = device_private(self);
70 struct fdt_attach_args * const faa = aux;
71 const int phandle = faa->faa_phandle;
72
73 bus_space_tag_t bst = faa->faa_bst;
74 bus_space_handle_t bsh;
75 bus_addr_t addr;
76 bus_size_t size;
77 void *ih;
78
79 sc->sc_dev = self;
80 sc->sc_type = COM_TYPE_BCMAUXUART;
81
82 int error = fdtbus_get_reg(phandle, 0, &addr, &size);
83 if (error) {
84 aprint_error_dev(sc->sc_dev, "unable to map device\n");
85 return;
86 }
87
88 if (com_is_console(bst, addr, &bsh) == 0 &&
89 bus_space_map(bst, addr, size, 0, &bsh) != 0) {
90 aprint_error(": can't map device\n");
91 return;
92 }
93
94 /* Enable clocks */
95 struct clk *clk;
96 for (int i = 0; (clk = fdtbus_clock_get_index(phandle, i)); i++) {
97 if (clk_enable(clk) != 0) {
98 aprint_error(": failed to enable clock #%d\n", i);
99 return;
100 }
101 /* First clock is UARTCLK */
102 if (i == 0)
103 sc->sc_frequency = clk_get_rate(clk);
104 }
105
106 sc->sc_frequency *= 2;
107
108 com_init_regs_stride(&sc->sc_regs, bst, bsh, addr, 2);
109
110 com_attach_subr(sc);
111 aprint_naive("\n");
112
113 char intrstr[128];
114 if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) {
115 aprint_error(": failed to decode interrupt\n");
116 return;
117 }
118
119 ih = fdtbus_intr_establish_xname(phandle, 0, IPL_SERIAL, FDT_INTR_MPSAFE,
120 comintr, sc, device_xname(sc->sc_dev));
121 if (ih == NULL) {
122 aprint_error_dev(self, "failed to establish interrupt %s\n",
123 intrstr);
124 return;
125 }
126 aprint_normal_dev(self, "interrupting on %s, clock %u Hz\n",
127 intrstr, sc->sc_frequency);
128 }
129
130 static int
bcmaux_com_console_match(int phandle)131 bcmaux_com_console_match(int phandle)
132 {
133
134 return of_compatible_match(phandle, compat_data);
135 }
136
137 static void
bcmaux_com_console_consinit(struct fdt_attach_args * faa,u_int uart_freq)138 bcmaux_com_console_consinit(struct fdt_attach_args *faa, u_int uart_freq)
139 {
140 const int phandle = faa->faa_phandle;
141 bus_space_tag_t bst = faa->faa_bst;
142 bus_space_handle_t dummy_bsh;
143 struct com_regs regs;
144 bus_addr_t addr;
145 tcflag_t flags;
146 int speed;
147
148 fdtbus_get_reg(phandle, 0, &addr, NULL);
149 speed = fdtbus_get_stdout_speed();
150 if (speed < 0)
151 speed = 115200; /* default */
152 flags = fdtbus_get_stdout_flags();
153
154 memset(&dummy_bsh, 0, sizeof(dummy_bsh));
155 com_init_regs_stride(®s, bst, dummy_bsh, addr, 2);
156
157 if (comcnattach1(®s, speed, uart_freq, COM_TYPE_BCMAUXUART,
158 flags))
159 panic("Cannot initialize bcm com console");
160
161 cn_set_magic("+++++");
162 }
163
164 static const struct fdt_console bcmaux_com_console = {
165 .match = bcmaux_com_console_match,
166 .consinit = bcmaux_com_console_consinit,
167 };
168
169 FDT_CONSOLE(bcmcom, &bcmaux_com_console);
170