1 /*-
2 * Copyright (c) 2016 Jared McNeill <[email protected]>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
19 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
21 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
22 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 #include <sys/kernel.h>
36 #include <sys/module.h>
37 #include <machine/bus.h>
38
39 #include <dev/uart/uart.h>
40 #include <dev/uart/uart_bus.h>
41 #include <dev/uart/uart_cpu_fdt.h>
42 #include <dev/uart/uart_dev_ns8250.h>
43
44 #include <dev/ofw/ofw_bus.h>
45 #include <dev/ofw/ofw_bus_subr.h>
46
47 #ifdef EXT_RESOURCES
48 #include <dev/extres/clk/clk.h>
49 #include <dev/extres/hwreset/hwreset.h>
50 #endif
51
52 #include "uart_if.h"
53
54 struct snps_softc {
55 struct ns8250_softc ns8250;
56
57 #ifdef EXT_RESOURCES
58 clk_t baudclk;
59 clk_t apb_pclk;
60 hwreset_t reset;
61 #endif
62 };
63
64 /*
65 * To use early printf on 64 bits Allwinner SoC, add to kernel config
66 * options SOCDEV_PA=0x0
67 * options SOCDEV_VA=0x40000000
68 * options EARLY_PRINTF
69 *
70 * To use early printf on 32 bits Allwinner SoC, add to kernel config
71 * options SOCDEV_PA=0x01C00000
72 * options SOCDEV_VA=0x10000000
73 * options EARLY_PRINTF
74 *
75 * remove the if 0
76 */
77 #if 0
78 #ifdef EARLY_PRINTF
79 static void
80 uart_snps_early_putc(int c)
81 {
82 volatile uint32_t *stat;
83 volatile uint32_t *tx;
84
85 #ifdef ALLWINNER_64
86 stat = (uint32_t *) (SOCDEV_VA + 0x1C2807C);
87 tx = (uint32_t *) (SOCDEV_VA + 0x1C28000);
88 #endif
89 #ifdef ALLWINNER_32
90 stat = (uint32_t *) (SOCDEV_VA + 0x2807C);
91 tx = (uint32_t *) (SOCDEV_VA + 0x28000);
92 #endif
93
94 while ((*stat & (1 << 2)) == 0)
95 continue;
96 *tx = c;
97 }
98 early_putc_t *early_putc = uart_snps_early_putc;
99 #endif /* EARLY_PRINTF */
100 #endif
101
102 static kobj_method_t snps_methods[] = {
103 KOBJMETHOD(uart_probe, ns8250_bus_probe),
104 KOBJMETHOD(uart_attach, ns8250_bus_attach),
105 KOBJMETHOD(uart_detach, ns8250_bus_detach),
106 KOBJMETHOD(uart_flush, ns8250_bus_flush),
107 KOBJMETHOD(uart_getsig, ns8250_bus_getsig),
108 KOBJMETHOD(uart_ioctl, ns8250_bus_ioctl),
109 KOBJMETHOD(uart_ipend, ns8250_bus_ipend),
110 KOBJMETHOD(uart_param, ns8250_bus_param),
111 KOBJMETHOD(uart_receive, ns8250_bus_receive),
112 KOBJMETHOD(uart_setsig, ns8250_bus_setsig),
113 KOBJMETHOD(uart_transmit, ns8250_bus_transmit),
114 KOBJMETHOD(uart_grab, ns8250_bus_grab),
115 KOBJMETHOD(uart_ungrab, ns8250_bus_ungrab),
116 KOBJMETHOD_END
117 };
118
119 struct uart_class uart_snps_class = {
120 "snps",
121 snps_methods,
122 sizeof(struct snps_softc),
123 .uc_ops = &uart_ns8250_ops,
124 .uc_range = 8,
125 .uc_rclk = 0,
126 };
127
128 static struct ofw_compat_data compat_data[] = {
129 { "snps,dw-apb-uart", (uintptr_t)&uart_snps_class },
130 { "marvell,armada-38x-uart", (uintptr_t)&uart_snps_class },
131 { NULL, (uintptr_t)NULL }
132 };
133 UART_FDT_CLASS(compat_data);
134
135 #ifdef EXT_RESOURCES
136 static int
snps_get_clocks(device_t dev,clk_t * baudclk,clk_t * apb_pclk)137 snps_get_clocks(device_t dev, clk_t *baudclk, clk_t *apb_pclk)
138 {
139
140 *baudclk = NULL;
141 *apb_pclk = NULL;
142
143 /* Baud clock is either named "baudclk", or there is a single
144 * unnamed clock.
145 */
146 if (clk_get_by_ofw_name(dev, 0, "baudclk", baudclk) != 0 &&
147 clk_get_by_ofw_index(dev, 0, 0, baudclk) != 0)
148 return (ENOENT);
149
150 /* APB peripheral clock is optional */
151 (void)clk_get_by_ofw_name(dev, 0, "apb_pclk", apb_pclk);
152
153 return (0);
154 }
155 #endif
156
157 static int
snps_probe(device_t dev)158 snps_probe(device_t dev)
159 {
160 struct snps_softc *sc;
161 struct uart_class *uart_class;
162 phandle_t node;
163 uint32_t shift, iowidth, clock;
164 uint64_t freq;
165 int error;
166 #ifdef EXT_RESOURCES
167 clk_t baudclk, apb_pclk;
168 hwreset_t reset;
169 #endif
170
171 if (!ofw_bus_status_okay(dev))
172 return (ENXIO);
173
174 uart_class = (struct uart_class *)ofw_bus_search_compatible(dev,
175 compat_data)->ocd_data;
176 if (uart_class == NULL)
177 return (ENXIO);
178
179 freq = 0;
180 sc = device_get_softc(dev);
181 sc->ns8250.base.sc_class = uart_class;
182
183 node = ofw_bus_get_node(dev);
184 if (OF_getencprop(node, "reg-shift", &shift, sizeof(shift)) <= 0)
185 shift = 0;
186 if (OF_getencprop(node, "reg-io-width", &iowidth, sizeof(iowidth)) <= 0)
187 iowidth = 1;
188 if (OF_getencprop(node, "clock-frequency", &clock, sizeof(clock)) <= 0)
189 clock = 0;
190
191 #ifdef EXT_RESOURCES
192 if (hwreset_get_by_ofw_idx(dev, 0, 0, &reset) == 0) {
193 error = hwreset_deassert(reset);
194 if (error != 0) {
195 device_printf(dev, "cannot de-assert reset\n");
196 return (error);
197 }
198 }
199
200 if (snps_get_clocks(dev, &baudclk, &apb_pclk) == 0) {
201 error = clk_enable(baudclk);
202 if (error != 0) {
203 device_printf(dev, "cannot enable baud clock\n");
204 return (error);
205 }
206 if (apb_pclk != NULL) {
207 error = clk_enable(apb_pclk);
208 if (error != 0) {
209 device_printf(dev,
210 "cannot enable peripheral clock\n");
211 return (error);
212 }
213 }
214
215 if (clock == 0) {
216 error = clk_get_freq(baudclk, &freq);
217 if (error != 0) {
218 device_printf(dev, "cannot get frequency\n");
219 return (error);
220 }
221 clock = (uint32_t)freq;
222 }
223 }
224 #endif
225
226 if (bootverbose && clock == 0)
227 device_printf(dev, "could not determine frequency\n");
228
229 error = uart_bus_probe(dev, (int)shift, (int)iowidth, (int)clock, 0, 0, UART_F_BUSY_DETECT);
230 if (error != 0)
231 return (error);
232
233 #ifdef EXT_RESOURCES
234 /* XXX uart_bus_probe has changed the softc, so refresh it */
235 sc = device_get_softc(dev);
236
237 /* Store clock and reset handles for detach */
238 sc->baudclk = baudclk;
239 sc->apb_pclk = apb_pclk;
240 sc->reset = reset;
241 #endif
242
243 return (0);
244 }
245
246 static int
snps_detach(device_t dev)247 snps_detach(device_t dev)
248 {
249 #ifdef EXT_RESOURCES
250 struct snps_softc *sc;
251 clk_t baudclk, apb_pclk;
252 hwreset_t reset;
253 #endif
254 int error;
255
256 #ifdef EXT_RESOURCES
257 sc = device_get_softc(dev);
258 baudclk = sc->baudclk;
259 apb_pclk = sc->apb_pclk;
260 reset = sc->reset;
261 #endif
262
263 error = uart_bus_detach(dev);
264 if (error != 0)
265 return (error);
266
267 #ifdef EXT_RESOURCES
268 if (reset != NULL) {
269 error = hwreset_assert(reset);
270 if (error != 0) {
271 device_printf(dev, "cannot assert reset\n");
272 return (error);
273 }
274 hwreset_release(reset);
275 }
276 if (apb_pclk != NULL) {
277 error = clk_release(apb_pclk);
278 if (error != 0) {
279 device_printf(dev, "cannot release peripheral clock\n");
280 return (error);
281 }
282 }
283 if (baudclk != NULL) {
284 error = clk_release(baudclk);
285 if (error != 0) {
286 device_printf(dev, "cannot release baud clock\n");
287 return (error);
288 }
289 }
290 #endif
291
292 return (0);
293 }
294
295 static device_method_t snps_bus_methods[] = {
296 /* Device interface */
297 DEVMETHOD(device_probe, snps_probe),
298 DEVMETHOD(device_attach, uart_bus_attach),
299 DEVMETHOD(device_detach, snps_detach),
300 DEVMETHOD_END
301 };
302
303 static driver_t snps_uart_driver = {
304 uart_driver_name,
305 snps_bus_methods,
306 sizeof(struct snps_softc)
307 };
308
309 DRIVER_MODULE(uart_snps, simplebus, snps_uart_driver, uart_devclass, 0, 0);
310