1 /* $NetBSD: dw_apb_uart.c,v 1.12 2022/04/08 10:17:54 andvar 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 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 1.12 2022/04/08 10:17:54 andvar 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 struct device_compatible_entry compat_data[] = {
49 { .compat = "snps,dw-apb-uart" },
50 DEVICE_COMPAT_EOL
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
dw_apb_uart_match(device_t parent,cfdata_t cf,void * aux)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_compatible_match(faa->faa_phandle, compat_data);
71 }
72
73 static void
dw_apb_uart_attach(device_t parent,device_t self,void * aux)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 const int phandle = faa->faa_phandle;
80 bus_space_tag_t bst = faa->faa_bst;
81 bus_space_handle_t bsh;
82 char intrstr[128];
83 bus_addr_t addr;
84 bus_size_t size;
85 u_int reg_shift, reg_iowidth;
86 int error;
87
88 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
89 aprint_error(": couldn't get registers\n");
90 return;
91 }
92
93 if (of_getprop_uint32(phandle, "reg-shift", ®_shift)) {
94 /* missing or bad reg-shift property, assume 2 */
95 reg_shift = 2;
96 }
97 if (of_getprop_uint32(phandle, "reg-io-width", ®_iowidth)) {
98 /* missing or bad reg-io-width property, assume 1 */
99 reg_iowidth = 1;
100 }
101
102 sc->sc_dev = self;
103
104 ssc->ssc_clk = fdtbus_clock_get_index(phandle, 0);
105 if (ssc->ssc_clk == NULL) {
106 aprint_error(": couldn't get clock\n");
107 return;
108 }
109 if (clk_enable(ssc->ssc_clk) != 0) {
110 aprint_error(": couldn't enable clock\n");
111 return;
112 }
113
114 ssc->ssc_pclk = fdtbus_clock_get(phandle, "apb_pclk");
115 if (ssc->ssc_pclk != NULL && clk_enable(ssc->ssc_pclk) != 0) {
116 aprint_error(": couldn't enable peripheral clock\n");
117 return;
118 }
119
120 ssc->ssc_rst = fdtbus_reset_get_index(phandle, 0);
121 if (ssc->ssc_rst && fdtbus_reset_deassert(ssc->ssc_rst) != 0) {
122 aprint_error(": couldn't de-assert reset\n");
123 return;
124 }
125
126 sc->sc_frequency = clk_get_rate(ssc->ssc_clk);
127 sc->sc_type = COM_TYPE_DW_APB;
128
129 error = bus_space_map(bst, addr, size, 0, &bsh);
130 if (error) {
131 aprint_error(": couldn't map %#" PRIx64 ": %d", (uint64_t)addr, error);
132 return;
133 }
134
135 com_init_regs_stride_width(&sc->sc_regs, bst, bsh, addr, reg_shift, reg_iowidth);
136
137 com_attach_subr(sc);
138
139 if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) {
140 aprint_error_dev(self, "failed to decode interrupt\n");
141 return;
142 }
143
144 ssc->ssc_ih = fdtbus_intr_establish_xname(phandle, 0,
145 IPL_SERIAL, FDT_INTR_MPSAFE, comintr, sc, device_xname(self));
146 if (ssc->ssc_ih == NULL) {
147 aprint_error_dev(self, "failed to establish interrupt on %s\n",
148 intrstr);
149 }
150 aprint_normal_dev(self, "interrupting on %s\n", intrstr);
151 }
152
153 /*
154 * Console support
155 */
156
157 static int
dw_apb_uart_console_match(int phandle)158 dw_apb_uart_console_match(int phandle)
159 {
160 return of_compatible_match(phandle, compat_data);
161 }
162
163 static void
dw_apb_uart_console_consinit(struct fdt_attach_args * faa,u_int uart_freq)164 dw_apb_uart_console_consinit(struct fdt_attach_args *faa, u_int uart_freq)
165 {
166 const int phandle = faa->faa_phandle;
167 bus_space_tag_t bst = faa->faa_bst;
168 bus_space_handle_t dummy_bsh;
169 struct com_regs regs;
170 bus_addr_t addr;
171 tcflag_t flags;
172 u_int reg_shift, reg_iowidth;
173 int speed;
174
175 fdtbus_get_reg(phandle, 0, &addr, NULL);
176 speed = fdtbus_get_stdout_speed();
177 if (speed < 0)
178 speed = 115200; /* default */
179 flags = fdtbus_get_stdout_flags();
180
181 if (of_getprop_uint32(phandle, "reg-shift", ®_shift)) {
182 /* missing or bad reg-shift property, assume 2 */
183 reg_shift = 2;
184 }
185 if (of_getprop_uint32(phandle, "reg-io-width", ®_iowidth)) {
186 /* missing or bad reg-io-width property, assume 1 */
187 reg_iowidth = 1;
188 }
189
190 memset(&dummy_bsh, 0, sizeof(dummy_bsh));
191 com_init_regs_stride_width(®s, bst, dummy_bsh, addr, reg_shift, reg_iowidth);
192
193 if (comcnattach1(®s, speed, uart_freq, COM_TYPE_DW_APB, flags))
194 panic("Cannot initialize dw-apb-uart console");
195 }
196
197 static const struct fdt_console dw_apb_uart_console = {
198 .match = dw_apb_uart_console_match,
199 .consinit = dw_apb_uart_console_consinit,
200 };
201
202 FDT_CONSOLE(dw_apb_uart, &dw_apb_uart_console);
203