dw_apb_uart.c revision 1.9 1 /* $NetBSD: dw_apb_uart.c,v 1.9 2021/01/15 20:50:49 ryo Exp $ */
2
3 /*-
4 * Copyright (c) 2017 Jared McNeill <jmcneill (at) 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30
31 __KERNEL_RCSID(1, "$NetBSD: dw_apb_uart.c,v 1.9 2021/01/15 20:50:49 ryo Exp $");
32
33 #include <sys/param.h>
34 #include <sys/bus.h>
35 #include <sys/device.h>
36 #include <sys/intr.h>
37 #include <sys/systm.h>
38 #include <sys/time.h>
39 #include <sys/termios.h>
40
41 #include <dev/ic/comvar.h>
42
43 #include <dev/fdt/fdtvar.h>
44
45 static int dw_apb_uart_match(device_t, cfdata_t, void *);
46 static void dw_apb_uart_attach(device_t, device_t, void *);
47
48 static const char * const compatible[] = {
49 "snps,dw-apb-uart",
50 NULL
51 };
52
53 struct dw_apb_uart_softc {
54 struct com_softc ssc_sc;
55 void *ssc_ih;
56
57 struct clk *ssc_clk;
58 struct clk *ssc_pclk;
59 struct fdtbus_reset *ssc_rst;
60 };
61
62 CFATTACH_DECL_NEW(dw_apb_uart, sizeof(struct dw_apb_uart_softc),
63 dw_apb_uart_match, dw_apb_uart_attach, NULL, NULL);
64
65 static int
66 dw_apb_uart_match(device_t parent, cfdata_t cf, void *aux)
67 {
68 struct fdt_attach_args * const faa = aux;
69
70 return of_match_compatible(faa->faa_phandle, compatible);
71 }
72
73 static void
74 dw_apb_uart_attach(device_t parent, device_t self, void *aux)
75 {
76 struct dw_apb_uart_softc * const ssc = device_private(self);
77 struct com_softc * const sc = &ssc->ssc_sc;
78 struct fdt_attach_args * const faa = aux;
79 bus_space_tag_t bst = faa->faa_bst;
80 bus_space_handle_t bsh;
81 char intrstr[128];
82 bus_addr_t addr;
83 bus_size_t size;
84 u_int reg_shift;
85 int error;
86
87 if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) {
88 aprint_error(": couldn't get registers\n");
89 return;
90 }
91
92 if (of_getprop_uint32(faa->faa_phandle, "reg-shift", ®_shift)) {
93 /* missing or bad reg-shift property, assume 2 */
94 reg_shift = 2;
95 }
96
97 sc->sc_dev = self;
98
99 ssc->ssc_clk = fdtbus_clock_get_index(faa->faa_phandle, 0);
100 if (ssc->ssc_clk == NULL) {
101 aprint_error(": couldn't get clock\n");
102 return;
103 }
104 if (clk_enable(ssc->ssc_clk) != 0) {
105 aprint_error(": couldn't enable clock\n");
106 return;
107 }
108
109 ssc->ssc_pclk = fdtbus_clock_get(faa->faa_phandle, "apb_pclk");
110 if (ssc->ssc_pclk != NULL && clk_enable(ssc->ssc_pclk) != 0) {
111 aprint_error(": couldn't enable peripheral clock\n");
112 return;
113 }
114
115 ssc->ssc_rst = fdtbus_reset_get_index(faa->faa_phandle, 0);
116 if (ssc->ssc_rst && fdtbus_reset_deassert(ssc->ssc_rst) != 0) {
117 aprint_error(": couldn't de-assert reset\n");
118 return;
119 }
120
121 sc->sc_frequency = clk_get_rate(ssc->ssc_clk);
122 sc->sc_type = COM_TYPE_DW_APB;
123
124 error = bus_space_map(bst, addr, size, 0, &bsh);
125 if (error) {
126 aprint_error(": couldn't map %#" PRIx64 ": %d", (uint64_t)addr, error);
127 return;
128 }
129
130 com_init_regs_stride(&sc->sc_regs, bst, bsh, addr, reg_shift);
131
132 com_attach_subr(sc);
133
134 if (!fdtbus_intr_str(faa->faa_phandle, 0, intrstr, sizeof(intrstr))) {
135 aprint_error_dev(self, "failed to decode interrupt\n");
136 return;
137 }
138
139 ssc->ssc_ih = fdtbus_intr_establish_xname(faa->faa_phandle, 0,
140 IPL_SERIAL, FDT_INTR_MPSAFE, comintr, sc, device_xname(self));
141 if (ssc->ssc_ih == NULL) {
142 aprint_error_dev(self, "failed to establish interrupt on %s\n",
143 intrstr);
144 }
145 aprint_normal_dev(self, "interrupting on %s\n", intrstr);
146 }
147
148 /*
149 * Console support
150 */
151
152 static int
153 dw_apb_uart_console_match(int phandle)
154 {
155 return of_match_compatible(phandle, compatible);
156 }
157
158 static void
159 dw_apb_uart_console_consinit(struct fdt_attach_args *faa, u_int uart_freq)
160 {
161 const int phandle = faa->faa_phandle;
162 bus_space_tag_t bst = faa->faa_bst;
163 bus_space_handle_t dummy_bsh;
164 struct com_regs regs;
165 bus_addr_t addr;
166 tcflag_t flags;
167 u_int reg_shift;
168 int speed;
169
170 fdtbus_get_reg(phandle, 0, &addr, NULL);
171 speed = fdtbus_get_stdout_speed();
172 if (speed < 0)
173 speed = 115200; /* default */
174 flags = fdtbus_get_stdout_flags();
175
176 if (of_getprop_uint32(phandle, "reg-shift", ®_shift)) {
177 /* missing or bad reg-shift property, assume 2 */
178 reg_shift = 2;
179 }
180
181 memset(&dummy_bsh, 0, sizeof(dummy_bsh));
182 com_init_regs_stride(®s, bst, dummy_bsh, addr, reg_shift);
183
184 if (comcnattach1(®s, speed, uart_freq, COM_TYPE_DW_APB, flags))
185 panic("Cannot initialize dw-apb-uart console");
186 }
187
188 static const struct fdt_console dw_apb_uart_console = {
189 .match = dw_apb_uart_console_match,
190 .consinit = dw_apb_uart_console_consinit,
191 };
192
193 FDT_CONSOLE(dw_apb_uart, &dw_apb_uart_console);
194