xref: /openbmc/u-boot/drivers/serial/sandbox.c (revision 6e87ae1c)
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 /*
8  * This provide a test serial port. It provides an emulated serial port where
9  * a test program and read out the serial output and inject serial input for
10  * U-Boot.
11  */
12 
13 #include <common.h>
14 #include <dm.h>
15 #include <fdtdec.h>
16 #include <lcd.h>
17 #include <os.h>
18 #include <serial.h>
19 #include <video.h>
20 #include <linux/compiler.h>
21 #include <asm/state.h>
22 
23 DECLARE_GLOBAL_DATA_PTR;
24 
25 /*
26  *
27  *   serial_buf: A buffer that holds keyboard characters for the
28  *		 Sandbox U-Boot.
29  *
30  * invariants:
31  *   serial_buf_write		 == serial_buf_read -> empty buffer
32  *   (serial_buf_write + 1) % 16 == serial_buf_read -> full buffer
33  */
34 static char serial_buf[16];
35 static unsigned int serial_buf_write;
36 static unsigned int serial_buf_read;
37 
38 struct sandbox_serial_platdata {
39 	int colour;	/* Text colour to use for output, -1 for none */
40 };
41 
42 struct sandbox_serial_priv {
43 	bool start_of_line;
44 };
45 
46 /**
47  * output_ansi_colour() - Output an ANSI colour code
48  *
49  * @colour: Colour to output (0-7)
50  */
51 static void output_ansi_colour(int colour)
52 {
53 	char ansi_code[] = "\x1b[1;3Xm";
54 
55 	ansi_code[5] = '0' + colour;
56 	os_write(1, ansi_code, sizeof(ansi_code) - 1);
57 }
58 
59 static void output_ansi_reset(void)
60 {
61 	os_write(1, "\x1b[0m", 4);
62 }
63 
64 static int sandbox_serial_probe(struct udevice *dev)
65 {
66 	struct sandbox_state *state = state_get_current();
67 	struct sandbox_serial_priv *priv = dev_get_priv(dev);
68 
69 	if (state->term_raw != STATE_TERM_COOKED)
70 		os_tty_raw(0, state->term_raw == STATE_TERM_RAW_WITH_SIGS);
71 	priv->start_of_line = 0;
72 
73 	return 0;
74 }
75 
76 static int sandbox_serial_remove(struct udevice *dev)
77 {
78 	struct sandbox_serial_platdata *plat = dev->platdata;
79 
80 	if (plat->colour != -1)
81 		output_ansi_reset();
82 
83 	return 0;
84 }
85 
86 static int sandbox_serial_putc(struct udevice *dev, const char ch)
87 {
88 	struct sandbox_serial_priv *priv = dev_get_priv(dev);
89 	struct sandbox_serial_platdata *plat = dev->platdata;
90 
91 	if (priv->start_of_line && plat->colour != -1) {
92 		priv->start_of_line = false;
93 		output_ansi_colour(plat->colour);
94 	}
95 
96 	os_write(1, &ch, 1);
97 	if (ch == '\n')
98 		priv->start_of_line = true;
99 
100 	return 0;
101 }
102 
103 static unsigned int increment_buffer_index(unsigned int index)
104 {
105 	return (index + 1) % ARRAY_SIZE(serial_buf);
106 }
107 
108 static int sandbox_serial_pending(struct udevice *dev, bool input)
109 {
110 	const unsigned int next_index =
111 		increment_buffer_index(serial_buf_write);
112 	ssize_t count;
113 
114 	if (!input)
115 		return 0;
116 
117 	os_usleep(100);
118 #ifndef CONFIG_SPL_BUILD
119 	video_sync_all();
120 #endif
121 	if (next_index == serial_buf_read)
122 		return 1;	/* buffer full */
123 
124 	count = os_read_no_block(0, &serial_buf[serial_buf_write], 1);
125 	if (count == 1)
126 		serial_buf_write = next_index;
127 
128 	return serial_buf_write != serial_buf_read;
129 }
130 
131 static int sandbox_serial_getc(struct udevice *dev)
132 {
133 	int result;
134 
135 	if (!sandbox_serial_pending(dev, true))
136 		return -EAGAIN;	/* buffer empty */
137 
138 	result = serial_buf[serial_buf_read];
139 	serial_buf_read = increment_buffer_index(serial_buf_read);
140 	return result;
141 }
142 
143 static const char * const ansi_colour[] = {
144 	"black", "red", "green", "yellow", "blue", "megenta", "cyan",
145 	"white",
146 };
147 
148 static int sandbox_serial_ofdata_to_platdata(struct udevice *dev)
149 {
150 	struct sandbox_serial_platdata *plat = dev->platdata;
151 	const char *colour;
152 	int i;
153 
154 	plat->colour = -1;
155 	colour = fdt_getprop(gd->fdt_blob, dev_of_offset(dev),
156 			     "sandbox,text-colour", NULL);
157 	if (colour) {
158 		for (i = 0; i < ARRAY_SIZE(ansi_colour); i++) {
159 			if (!strcmp(colour, ansi_colour[i])) {
160 				plat->colour = i;
161 				break;
162 			}
163 		}
164 	}
165 
166 	return 0;
167 }
168 
169 static const struct dm_serial_ops sandbox_serial_ops = {
170 	.putc = sandbox_serial_putc,
171 	.pending = sandbox_serial_pending,
172 	.getc = sandbox_serial_getc,
173 };
174 
175 static const struct udevice_id sandbox_serial_ids[] = {
176 	{ .compatible = "sandbox,serial" },
177 	{ }
178 };
179 
180 U_BOOT_DRIVER(serial_sandbox) = {
181 	.name	= "serial_sandbox",
182 	.id	= UCLASS_SERIAL,
183 	.of_match = sandbox_serial_ids,
184 	.ofdata_to_platdata = sandbox_serial_ofdata_to_platdata,
185 	.platdata_auto_alloc_size = sizeof(struct sandbox_serial_platdata),
186 	.priv_auto_alloc_size = sizeof(struct sandbox_serial_priv),
187 	.probe = sandbox_serial_probe,
188 	.remove = sandbox_serial_remove,
189 	.ops	= &sandbox_serial_ops,
190 	.flags = DM_FLAG_PRE_RELOC,
191 };
192 
193 static const struct sandbox_serial_platdata platdata_non_fdt = {
194 	.colour = -1,
195 };
196 
197 U_BOOT_DEVICE(serial_sandbox_non_fdt) = {
198 	.name = "serial_sandbox",
199 	.platdata = &platdata_non_fdt,
200 };
201