1 /*
2  * (C) Copyright 2008-2011 Michal Simek <monstr@monstr.eu>
3  * Clean driver and add xilinx constant from header file
4  *
5  * (C) Copyright 2004 Atmark Techno, Inc.
6  * Yasushi SHOJI <yashi@atmark-techno.com>
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <config.h>
12 #include <common.h>
13 #include <asm/io.h>
14 #include <linux/compiler.h>
15 #include <serial.h>
16 
17 #define SR_TX_FIFO_FULL		0x08 /* transmit FIFO full */
18 #define SR_RX_FIFO_VALID_DATA	0x01 /* data in receive FIFO */
19 #define SR_RX_FIFO_FULL		0x02 /* receive FIFO full */
20 
21 #define ULITE_CONTROL_RST_TX	0x01
22 #define ULITE_CONTROL_RST_RX	0x02
23 
24 struct uartlite {
25 	unsigned int rx_fifo;
26 	unsigned int tx_fifo;
27 	unsigned int status;
28 	unsigned int control;
29 };
30 
31 static struct uartlite *userial_ports[4] = {
32 #ifdef XILINX_UARTLITE_BASEADDR
33 	[0] = (struct uartlite *)XILINX_UARTLITE_BASEADDR,
34 #endif
35 #ifdef XILINX_UARTLITE_BASEADDR1
36 	[1] = (struct uartlite *)XILINX_UARTLITE_BASEADDR1,
37 #endif
38 #ifdef XILINX_UARTLITE_BASEADDR2
39 	[2] = (struct uartlite *)XILINX_UARTLITE_BASEADDR2,
40 #endif
41 #ifdef XILINX_UARTLITE_BASEADDR3
42 	[3] = (struct uartlite *)XILINX_UARTLITE_BASEADDR3
43 #endif
44 };
45 
46 static void uartlite_serial_putc(const char c, const int port)
47 {
48 	struct uartlite *regs = userial_ports[port];
49 
50 	if (c == '\n')
51 		uartlite_serial_putc('\r', port);
52 
53 	while (in_be32(&regs->status) & SR_TX_FIFO_FULL)
54 		;
55 	out_be32(&regs->tx_fifo, c & 0xff);
56 }
57 
58 static void uartlite_serial_puts(const char *s, const int port)
59 {
60 	while (*s)
61 		uartlite_serial_putc(*s++, port);
62 }
63 
64 static int uartlite_serial_getc(const int port)
65 {
66 	struct uartlite *regs = userial_ports[port];
67 
68 	while (!(in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA))
69 		;
70 	return in_be32(&regs->rx_fifo) & 0xff;
71 }
72 
73 static int uartlite_serial_tstc(const int port)
74 {
75 	struct uartlite *regs = userial_ports[port];
76 
77 	return in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA;
78 }
79 
80 static int uartlite_serial_init(const int port)
81 {
82 	struct uartlite *regs = userial_ports[port];
83 
84 	if (regs) {
85 		out_be32(&regs->control, 0);
86 		out_be32(&regs->control,
87 			 ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX);
88 		in_be32(&regs->control);
89 		return 0;
90 	}
91 
92 	return -1;
93 }
94 
95 /* Multi serial device functions */
96 #define DECLARE_ESERIAL_FUNCTIONS(port) \
97 	static int userial##port##_init(void) \
98 				{ return uartlite_serial_init(port); } \
99 	static void userial##port##_setbrg(void) {} \
100 	static int userial##port##_getc(void) \
101 				{ return uartlite_serial_getc(port); } \
102 	static int userial##port##_tstc(void) \
103 				{ return uartlite_serial_tstc(port); } \
104 	static void userial##port##_putc(const char c) \
105 				{ uartlite_serial_putc(c, port); } \
106 	static void userial##port##_puts(const char *s) \
107 				{ uartlite_serial_puts(s, port); }
108 
109 /* Serial device descriptor */
110 #define INIT_ESERIAL_STRUCTURE(port, __name) {	\
111 	.name	= __name,			\
112 	.start	= userial##port##_init,		\
113 	.stop	= NULL,				\
114 	.setbrg	= userial##port##_setbrg,	\
115 	.getc	= userial##port##_getc,		\
116 	.tstc	= userial##port##_tstc,		\
117 	.putc	= userial##port##_putc,		\
118 	.puts	= userial##port##_puts,		\
119 }
120 
121 DECLARE_ESERIAL_FUNCTIONS(0);
122 struct serial_device uartlite_serial0_device =
123 	INIT_ESERIAL_STRUCTURE(0, "ttyUL0");
124 DECLARE_ESERIAL_FUNCTIONS(1);
125 struct serial_device uartlite_serial1_device =
126 	INIT_ESERIAL_STRUCTURE(1, "ttyUL1");
127 DECLARE_ESERIAL_FUNCTIONS(2);
128 struct serial_device uartlite_serial2_device =
129 	INIT_ESERIAL_STRUCTURE(2, "ttyUL2");
130 DECLARE_ESERIAL_FUNCTIONS(3);
131 struct serial_device uartlite_serial3_device =
132 	INIT_ESERIAL_STRUCTURE(3, "ttyUL3");
133 
134 __weak struct serial_device *default_serial_console(void)
135 {
136 	if (userial_ports[0])
137 		return &uartlite_serial0_device;
138 	if (userial_ports[1])
139 		return &uartlite_serial1_device;
140 	if (userial_ports[2])
141 		return &uartlite_serial2_device;
142 	if (userial_ports[3])
143 		return &uartlite_serial3_device;
144 
145 	return NULL;
146 }
147 
148 void uartlite_serial_initialize(void)
149 {
150 #ifdef XILINX_UARTLITE_BASEADDR
151 	serial_register(&uartlite_serial0_device);
152 #endif /* XILINX_UARTLITE_BASEADDR */
153 #ifdef XILINX_UARTLITE_BASEADDR1
154 	serial_register(&uartlite_serial1_device);
155 #endif /* XILINX_UARTLITE_BASEADDR1 */
156 #ifdef XILINX_UARTLITE_BASEADDR2
157 	serial_register(&uartlite_serial2_device);
158 #endif /* XILINX_UARTLITE_BASEADDR2 */
159 #ifdef XILINX_UARTLITE_BASEADDR3
160 	serial_register(&uartlite_serial3_device);
161 #endif /* XILINX_UARTLITE_BASEADDR3 */
162 }
163