xref: /freebsd-13-stable/sys/mips/atheros/uart_bus_ar933x.c (revision 3bc80996974a61a4223eae4c1ccd47b6ee32a48a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2012, Adrian Chadd <adrian@FreeBSD.org>
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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  */
27 #include "opt_uart.h"
28 
29 #include <sys/cdefs.h>
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 
37 #include <machine/bus.h>
38 
39 #include <dev/uart/uart.h>
40 #include <dev/uart/uart_cpu.h>
41 #include <dev/uart/uart_bus.h>
42 
43 #include <mips/atheros/ar71xxreg.h>
44 #include <mips/atheros/ar71xx_cpudef.h>
45 
46 #include <mips/atheros/uart_dev_ar933x.h>
47 #ifdef	EARLY_PRINTF
48 #include <mips/atheros/ar933x_uart.h>
49 #endif
50 
51 #include "uart_if.h"
52 
53 static int uart_ar933x_probe(device_t dev);
54 extern struct uart_class uart_ar933x_uart_class;
55 
56 static device_method_t uart_ar933x_methods[] = {
57 	/* Device interface */
58 	DEVMETHOD(device_probe,		uart_ar933x_probe),
59 	DEVMETHOD(device_attach,	uart_bus_attach),
60 	DEVMETHOD(device_detach,	uart_bus_detach),
61 	{ 0, 0 }
62 };
63 
64 static driver_t uart_ar933x_driver = {
65 	uart_driver_name,
66 	uart_ar933x_methods,
67 	sizeof(struct uart_softc),
68 };
69 
70 extern SLIST_HEAD(uart_devinfo_list, uart_devinfo) uart_sysdevs;
71 
72 static int
uart_ar933x_probe(device_t dev)73 uart_ar933x_probe(device_t dev)
74 {
75 	struct uart_softc *sc;
76 	uint64_t freq;
77 
78 	freq = ar71xx_uart_freq();
79 
80 	sc = device_get_softc(dev);
81 	sc->sc_sysdev = SLIST_FIRST(&uart_sysdevs);
82 	sc->sc_class = &uart_ar933x_class;
83 	bcopy(&sc->sc_sysdev->bas, &sc->sc_bas, sizeof(sc->sc_bas));
84 	sc->sc_sysdev->bas.regshft = 0;
85 	sc->sc_sysdev->bas.bst = mips_bus_space_generic;
86 	sc->sc_sysdev->bas.bsh = MIPS_PHYS_TO_KSEG1(AR71XX_UART_ADDR);
87 	sc->sc_bas.regshft = 0;
88 	sc->sc_bas.bst = mips_bus_space_generic;
89 	sc->sc_bas.bsh = MIPS_PHYS_TO_KSEG1(AR71XX_UART_ADDR);
90 
91 	return (uart_bus_probe(dev, 2, 0, freq, 0, 0, 0));
92 }
93 
94 /*
95  * Assume the UART is setup by the bootloader and just echo that.
96  */
97 #if	defined(EARLY_PRINTF)
98 static void
ar933x_early_putc(int c)99 ar933x_early_putc(int c)
100 {
101 	int i = 1000;
102 
103 	/* Wait until FIFO is clear */
104 	while ((i > 0) && (ATH_READ_REG(AR71XX_UART_ADDR + AR933X_UART_CS_REG) &
105 	     AR933X_UART_CS_TX_BUSY))
106 		i--;
107 
108 	/* Write it out */
109 	ATH_WRITE_REG(AR71XX_UART_ADDR + AR933X_UART_DATA_REG,
110 	    (c  & 0xff)| AR933X_UART_DATA_TX_CSR);
111 }
112 early_putc_t *early_putc = ar933x_early_putc;
113 #endif	/* EARLY_PRINTF */
114 
115 DRIVER_MODULE(uart, apb, uart_ar933x_driver, uart_devclass, 0, 0);
116