1/*-
2 * Copyright (c) 2009-2010 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Semihalf under sponsorship from
6 * the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/bus.h>
35#include <sys/kernel.h>
36#include <sys/module.h>
37
38#include <machine/bus.h>
39#include <machine/fdt.h>
40
41#include <dev/fdt/fdt_common.h>
42#include <dev/ofw/ofw_bus.h>
43#include <dev/ofw/ofw_bus_subr.h>
44#include <dev/uart/uart.h>
45#include <dev/uart/uart_bus.h>
46#include <dev/uart/uart_cpu.h>
47
48static int uart_fdt_probe(device_t);
49
50static device_method_t uart_fdt_methods[] = {
51	/* Device interface */
52	DEVMETHOD(device_probe,		uart_fdt_probe),
53	DEVMETHOD(device_attach,	uart_bus_attach),
54	DEVMETHOD(device_detach,	uart_bus_detach),
55	{ 0, 0 }
56};
57
58static driver_t uart_fdt_driver = {
59	uart_driver_name,
60	uart_fdt_methods,
61	sizeof(struct uart_softc),
62};
63
64static int
65uart_fdt_get_clock(phandle_t node, pcell_t *cell)
66{
67	pcell_t clock;
68
69	if ((OF_getprop(node, "clock-frequency", &clock,
70	    sizeof(clock))) <= 0)
71		return (ENXIO);
72
73	if (clock == 0)
74		/* Try to retrieve parent 'bus-frequency' */
75		/* XXX this should go to simple-bus fixup or so */
76		if ((OF_getprop(OF_parent(node), "bus-frequency", &clock,
77		    sizeof(clock))) <= 0)
78			clock = 0;
79
80	*cell = fdt32_to_cpu(clock);
81	return (0);
82}
83
84static int
85uart_fdt_get_shift(phandle_t node, pcell_t *cell)
86{
87	pcell_t shift;
88
89	if ((OF_getprop(node, "reg-shift", &shift, sizeof(shift))) <= 0)
90		shift = 0;
91	*cell = fdt32_to_cpu(shift);
92	return (0);
93}
94
95static int
96uart_fdt_probe(device_t dev)
97{
98	struct uart_softc *sc;
99	phandle_t node;
100	pcell_t clock, shift;
101	int err;
102
103	if (!ofw_bus_is_compatible(dev, "ns16550"))
104		return (ENXIO);
105
106	sc = device_get_softc(dev);
107	sc->sc_class = &uart_ns8250_class;
108
109	node = ofw_bus_get_node(dev);
110
111	if ((err = uart_fdt_get_clock(node, &clock)) != 0)
112		return (err);
113	uart_fdt_get_shift(node, &shift);
114
115	return (uart_bus_probe(dev, (int)shift, (int)clock, 0, 0));
116}
117
118DRIVER_MODULE(uart, simplebus, uart_fdt_driver, uart_devclass, 0, 0);
119
120/*
121 * UART console routines.
122 */
123bus_space_tag_t uart_bus_space_io;
124bus_space_tag_t uart_bus_space_mem;
125
126int
127uart_cpu_eqres(struct uart_bas *b1, struct uart_bas *b2)
128{
129
130	return ((b1->bsh == b2->bsh && b1->bst == b2->bst) ? 1 : 0);
131}
132
133int
134uart_cpu_getdev(int devtype, struct uart_devinfo *di)
135{
136	char buf[64];
137	struct uart_class *class;
138	phandle_t node, chosen;
139	pcell_t shift, br, rclk;
140	u_long start, size;
141	int err;
142
143	uart_bus_space_mem = fdtbus_bs_tag;
144	uart_bus_space_io = NULL;
145
146	/* Allow overriding the FDT uning the environment. */
147	class = &uart_ns8250_class;
148	err = uart_getenv(devtype, di, class);
149	if (!err)
150		return (0);
151
152	if (devtype != UART_DEV_CONSOLE)
153		return (ENXIO);
154
155	/*
156	 * Retrieve /chosen/std{in,out}.
157	 */
158	if ((chosen = OF_finddevice("/chosen")) == 0)
159		return (ENXIO);
160	if (OF_getprop(chosen, "stdin", buf, sizeof(buf)) <= 0)
161		return (ENXIO);
162	if ((node = OF_finddevice(buf)) == 0)
163		return (ENXIO);
164	if (OF_getprop(chosen, "stdout", buf, sizeof(buf)) <= 0)
165		return (ENXIO);
166	if (OF_finddevice(buf) != node)
167		/* Only stdin == stdout is supported. */
168		return (ENXIO);
169	/*
170	 * Retrieve serial attributes.
171	 */
172	uart_fdt_get_shift(node, &shift);
173
174	if (OF_getprop(node, "current-speed", &br, sizeof(br)) <= 0)
175		br = 0;
176	br = fdt32_to_cpu(br);
177
178	if ((err = uart_fdt_get_clock(node, &rclk)) != 0)
179		return (err);
180	/*
181	 * Finalize configuration.
182	 */
183	class = &uart_quicc_class;
184	if (fdt_is_compatible(node, "ns16550"))
185		class = &uart_ns8250_class;
186
187	di->bas.chan = 0;
188	di->bas.regshft = (u_int)shift;
189	di->baudrate = 0;
190	di->bas.rclk = (u_int)rclk;
191	di->ops = uart_getops(class);
192	di->databits = 8;
193	di->stopbits = 1;
194	di->parity = UART_PARITY_NONE;
195	di->bas.bst = uart_bus_space_mem;
196
197	err = fdt_regsize(node, &start, &size);
198	if (err)
199		return (ENXIO);
200	start += fdt_immr_va;
201
202	return (bus_space_map(di->bas.bst, start, size, 0, &di->bas.bsh));
203}
204