xref: /openbmc/u-boot/drivers/serial/sandbox.c (revision f1896c45cb2f7d8dbed27e784a6459a129fc0762)
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