xref: /openbmc/u-boot/drivers/serial/sandbox.c (revision 58008cba)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2011 The Chromium OS Authors.
4  */
5 
6 /*
7  * This provide a test serial port. It provides an emulated serial port where
8  * a test program and read out the serial output and inject serial input for
9  * U-Boot.
10  */
11 
12 #include <common.h>
13 #include <console.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 	if (state->term_raw != STATE_TERM_RAW)
74 		disable_ctrlc(1);
75 
76 	return 0;
77 }
78 
79 static int sandbox_serial_remove(struct udevice *dev)
80 {
81 	struct sandbox_serial_platdata *plat = dev->platdata;
82 
83 	if (plat->colour != -1)
84 		output_ansi_reset();
85 
86 	return 0;
87 }
88 
89 static int sandbox_serial_putc(struct udevice *dev, const char ch)
90 {
91 	struct sandbox_serial_priv *priv = dev_get_priv(dev);
92 	struct sandbox_serial_platdata *plat = dev->platdata;
93 
94 	if (priv->start_of_line && plat->colour != -1) {
95 		priv->start_of_line = false;
96 		output_ansi_colour(plat->colour);
97 	}
98 
99 	os_write(1, &ch, 1);
100 	if (ch == '\n')
101 		priv->start_of_line = true;
102 
103 	return 0;
104 }
105 
106 static unsigned int increment_buffer_index(unsigned int index)
107 {
108 	return (index + 1) % ARRAY_SIZE(serial_buf);
109 }
110 
111 static int sandbox_serial_pending(struct udevice *dev, bool input)
112 {
113 	const unsigned int next_index =
114 		increment_buffer_index(serial_buf_write);
115 	ssize_t count;
116 
117 	if (!input)
118 		return 0;
119 
120 	os_usleep(100);
121 #ifndef CONFIG_SPL_BUILD
122 	video_sync_all();
123 #endif
124 	if (next_index == serial_buf_read)
125 		return 1;	/* buffer full */
126 
127 	count = os_read_no_block(0, &serial_buf[serial_buf_write], 1);
128 	if (count == 1)
129 		serial_buf_write = next_index;
130 
131 	return serial_buf_write != serial_buf_read;
132 }
133 
134 static int sandbox_serial_getc(struct udevice *dev)
135 {
136 	int result;
137 
138 	if (!sandbox_serial_pending(dev, true))
139 		return -EAGAIN;	/* buffer empty */
140 
141 	result = serial_buf[serial_buf_read];
142 	serial_buf_read = increment_buffer_index(serial_buf_read);
143 	return result;
144 }
145 
146 static const char * const ansi_colour[] = {
147 	"black", "red", "green", "yellow", "blue", "megenta", "cyan",
148 	"white",
149 };
150 
151 static int sandbox_serial_ofdata_to_platdata(struct udevice *dev)
152 {
153 	struct sandbox_serial_platdata *plat = dev->platdata;
154 	const char *colour;
155 	int i;
156 
157 	plat->colour = -1;
158 	colour = fdt_getprop(gd->fdt_blob, dev_of_offset(dev),
159 			     "sandbox,text-colour", NULL);
160 	if (colour) {
161 		for (i = 0; i < ARRAY_SIZE(ansi_colour); i++) {
162 			if (!strcmp(colour, ansi_colour[i])) {
163 				plat->colour = i;
164 				break;
165 			}
166 		}
167 	}
168 
169 	return 0;
170 }
171 
172 static const struct dm_serial_ops sandbox_serial_ops = {
173 	.putc = sandbox_serial_putc,
174 	.pending = sandbox_serial_pending,
175 	.getc = sandbox_serial_getc,
176 };
177 
178 static const struct udevice_id sandbox_serial_ids[] = {
179 	{ .compatible = "sandbox,serial" },
180 	{ }
181 };
182 
183 U_BOOT_DRIVER(serial_sandbox) = {
184 	.name	= "serial_sandbox",
185 	.id	= UCLASS_SERIAL,
186 	.of_match = sandbox_serial_ids,
187 	.ofdata_to_platdata = sandbox_serial_ofdata_to_platdata,
188 	.platdata_auto_alloc_size = sizeof(struct sandbox_serial_platdata),
189 	.priv_auto_alloc_size = sizeof(struct sandbox_serial_priv),
190 	.probe = sandbox_serial_probe,
191 	.remove = sandbox_serial_remove,
192 	.ops	= &sandbox_serial_ops,
193 	.flags = DM_FLAG_PRE_RELOC,
194 };
195 
196 static const struct sandbox_serial_platdata platdata_non_fdt = {
197 	.colour = -1,
198 };
199 
200 U_BOOT_DEVICE(serial_sandbox_non_fdt) = {
201 	.name = "serial_sandbox",
202 	.platdata = &platdata_non_fdt,
203 };
204