1/*-
2 * Copyright (c) 2013 Ian Lepore
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 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include "opt_platform.h"
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/conf.h>
36#include <sys/kernel.h>
37#include <sys/sysctl.h>
38#include <machine/bus.h>
39
40#include <arm/ti/ti_prcm.h>
41
42#include <dev/fdt/fdt_common.h>
43#include <dev/ofw/ofw_bus.h>
44#include <dev/ofw/ofw_bus_subr.h>
45
46#include <dev/uart/uart.h>
47#include <dev/uart/uart_cpu.h>
48#include <dev/uart/uart_bus.h>
49#include <dev/uart/uart_dev_ns8250.h>
50
51#include "uart_if.h"
52
53/*
54 * High-level UART interface.
55 */
56struct ti8250_softc {
57	struct ns8250_softc ns8250_base;
58	/*uint32_t	mystuff;*/
59};
60
61#define	MDR1_REG		8
62#define	  MDR1_MODE_UART	0
63#define	  MDR1_MODE_DISABLE	7
64#define	SYSCC_REG		15
65#define	  SYSCC_SOFTRESET	(1 << 1)
66#define	SYSS_REG		16
67#define	  SYSS_STATUS_RESETDONE	(1 << 0)
68
69static int
70ti8250_bus_probe(struct uart_softc *sc)
71{
72	int status;
73	int devid;
74	clk_ident_t clkid;
75	pcell_t prop;
76	phandle_t node;
77
78	/*
79	 * Get the device id from FDT.  If it's not there we can't turn on the
80	 * right clocks, so bail, unless we're doing unit 0.  We assume that's
81	 * the serial console, whose clock isn't controllable anyway, and we
82	 * sure don't want to break the console because of a config error.
83	 */
84	node = ofw_bus_get_node(sc->sc_dev);
85	if ((OF_getprop(node, "uart-device-id", &prop, sizeof(prop))) <= 0) {
86		device_printf(sc->sc_dev,
87		    "missing uart-device-id attribute in FDT\n");
88		if (device_get_unit(sc->sc_dev) != 0)
89			return (ENXIO);
90		devid = 0;
91	} else
92		devid = fdt32_to_cpu(prop);
93
94	/* Enable clocks for this device.  We can't continue if that fails.  */
95	clkid = UART0_CLK + devid;
96	if ((status = ti_prcm_clk_enable(clkid)) != 0)
97		return (status);
98
99	/*
100	 * Set the hardware to disabled mode, do a full device reset, then set
101	 * it to uart mode.  Most devices will be reset-and-disabled already,
102	 * but you never know what a bootloader might have done.
103	 */
104	uart_setreg(&sc->sc_bas, MDR1_REG, MDR1_MODE_DISABLE);
105	uart_setreg(&sc->sc_bas, SYSCC_REG, SYSCC_SOFTRESET);
106	while (uart_getreg(&sc->sc_bas, SYSS_REG) & SYSS_STATUS_RESETDONE)
107		continue;
108	uart_setreg(&sc->sc_bas, MDR1_REG, MDR1_MODE_UART);
109
110	status = ns8250_bus_probe(sc);
111	if (status == 0)
112		device_set_desc(sc->sc_dev, "TI UART (16550 compatible)");
113
114	return (status);
115}
116
117static kobj_method_t ti8250_methods[] = {
118	KOBJMETHOD(uart_probe,		ti8250_bus_probe),
119
120	KOBJMETHOD(uart_attach,		ns8250_bus_attach),
121	KOBJMETHOD(uart_detach,		ns8250_bus_detach),
122	KOBJMETHOD(uart_flush,		ns8250_bus_flush),
123	KOBJMETHOD(uart_getsig,		ns8250_bus_getsig),
124	KOBJMETHOD(uart_ioctl,		ns8250_bus_ioctl),
125	KOBJMETHOD(uart_ipend,		ns8250_bus_ipend),
126	KOBJMETHOD(uart_param,		ns8250_bus_param),
127	KOBJMETHOD(uart_receive,	ns8250_bus_receive),
128	KOBJMETHOD(uart_setsig,		ns8250_bus_setsig),
129	KOBJMETHOD(uart_transmit,	ns8250_bus_transmit),
130	KOBJMETHOD_END
131};
132
133struct uart_class uart_ti8250_class = {
134	"ti8250",
135	ti8250_methods,
136	sizeof(struct ti8250_softc),
137	.uc_ops = &uart_ns8250_ops,
138	.uc_range = 0x88,
139	.uc_rclk = 48000000
140};
141
142