1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (c) 2014 The Chromium OS Authors.
8 #include <environment.h>
12 #include <stdio_dev.h>
15 #include <dm/device-internal.h>
16 #include <dm/of_access.h>
18 DECLARE_GLOBAL_DATA_PTR;
21 * Table with supported baudrates (defined in config_xyz.h)
23 static const unsigned long baudrate_table[] = CONFIG_SYS_BAUDRATE_TABLE;
25 #if !CONFIG_VAL(SYS_MALLOC_F_LEN)
26 #error "Serial is required before relocation - define CONFIG_$(SPL_)SYS_MALLOC_F_LEN to make this work"
29 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
30 static int serial_check_stdout(const void *blob, struct udevice **devp)
34 /* Check for a chosen console */
35 node = fdtdec_get_chosen_node(blob, "stdout-path");
37 const char *str, *p, *name;
40 * Deal with things like
41 * stdout-path = "serial0:115200n8";
43 * We need to look up the alias and then follow it to the
46 str = fdtdec_get_chosen_prop(blob, "stdout-path");
49 name = fdt_get_alias_namelen(blob, str,
50 p ? p - str : strlen(str));
52 node = fdt_path_offset(blob, name);
56 node = fdt_path_offset(blob, "console");
57 if (!uclass_get_device_by_of_offset(UCLASS_SERIAL, node, devp))
61 * If the console is not marked to be bound before relocation, bind it
64 if (node > 0 && !lists_bind_fdt(gd->dm_root, offset_to_ofnode(node),
66 if (!device_probe(*devp))
73 static void serial_find_console_or_panic(void)
75 const void *blob = gd->fdt_blob;
77 #ifdef CONFIG_SERIAL_SEARCH_ALL
81 if (CONFIG_IS_ENABLED(OF_PLATDATA)) {
82 uclass_first_device(UCLASS_SERIAL, &dev);
84 gd->cur_serial_dev = dev;
87 } else if (CONFIG_IS_ENABLED(OF_CONTROL) && blob) {
88 /* Live tree has support for stdout */
89 if (of_live_active()) {
90 struct device_node *np = of_get_stdout();
92 if (np && !uclass_get_device_by_ofnode(UCLASS_SERIAL,
93 np_to_ofnode(np), &dev)) {
94 gd->cur_serial_dev = dev;
98 if (!serial_check_stdout(blob, &dev)) {
99 gd->cur_serial_dev = dev;
104 if (!SPL_BUILD || !CONFIG_IS_ENABLED(OF_CONTROL) || !blob) {
106 * Try to use CONFIG_CONS_INDEX if available (it is numbered
109 * Failing that, get the device with sequence number 0, or in
110 * extremis just the first working serial device we can find.
111 * But we insist on having a console (even if it is silent).
113 #ifdef CONFIG_CONS_INDEX
114 #define INDEX (CONFIG_CONS_INDEX - 1)
119 #ifdef CONFIG_SERIAL_SEARCH_ALL
120 if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
121 !uclass_get_device(UCLASS_SERIAL, INDEX, &dev)) {
122 if (dev->flags & DM_FLAG_ACTIVATED) {
123 gd->cur_serial_dev = dev;
128 /* Search for any working device */
129 for (ret = uclass_first_device_check(UCLASS_SERIAL, &dev);
131 ret = uclass_next_device_check(&dev)) {
133 /* Device did succeed probing */
134 gd->cur_serial_dev = dev;
139 if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
140 !uclass_get_device(UCLASS_SERIAL, INDEX, &dev) ||
141 (!uclass_first_device(UCLASS_SERIAL, &dev) && dev)) {
142 gd->cur_serial_dev = dev;
150 #ifdef CONFIG_REQUIRE_SERIAL_CONSOLE
151 panic_str("No serial driver found");
154 #endif /* CONFIG_SERIAL_PRESENT */
156 /* Called prior to relocation */
157 int serial_init(void)
159 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
160 serial_find_console_or_panic();
161 gd->flags |= GD_FLG_SERIAL_READY;
167 /* Called after relocation */
168 void serial_initialize(void)
173 static void _serial_putc(struct udevice *dev, char ch)
175 struct dm_serial_ops *ops = serial_get_ops(dev);
179 _serial_putc(dev, '\r');
182 err = ops->putc(dev, ch);
183 } while (err == -EAGAIN);
186 static void _serial_puts(struct udevice *dev, const char *str)
189 _serial_putc(dev, *str++);
192 static int __serial_getc(struct udevice *dev)
194 struct dm_serial_ops *ops = serial_get_ops(dev);
198 err = ops->getc(dev);
201 } while (err == -EAGAIN);
203 return err >= 0 ? err : 0;
206 static int __serial_tstc(struct udevice *dev)
208 struct dm_serial_ops *ops = serial_get_ops(dev);
211 return ops->pending(dev, true);
216 #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
217 static int _serial_tstc(struct udevice *dev)
219 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
221 /* Read all available chars into the RX buffer */
222 while (__serial_tstc(dev)) {
223 upriv->buf[upriv->wr_ptr++] = __serial_getc(dev);
224 upriv->wr_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
227 return upriv->rd_ptr != upriv->wr_ptr ? 1 : 0;
230 static int _serial_getc(struct udevice *dev)
232 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
235 if (upriv->rd_ptr == upriv->wr_ptr)
236 return __serial_getc(dev);
238 val = upriv->buf[upriv->rd_ptr++];
239 upriv->rd_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
244 #else /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
246 static int _serial_getc(struct udevice *dev)
248 return __serial_getc(dev);
251 static int _serial_tstc(struct udevice *dev)
253 return __serial_tstc(dev);
255 #endif /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
257 void serial_putc(char ch)
259 if (gd->cur_serial_dev)
260 _serial_putc(gd->cur_serial_dev, ch);
263 void serial_puts(const char *str)
265 if (gd->cur_serial_dev)
266 _serial_puts(gd->cur_serial_dev, str);
269 int serial_getc(void)
271 if (!gd->cur_serial_dev)
274 return _serial_getc(gd->cur_serial_dev);
277 int serial_tstc(void)
279 if (!gd->cur_serial_dev)
282 return _serial_tstc(gd->cur_serial_dev);
285 void serial_setbrg(void)
287 struct dm_serial_ops *ops;
289 if (!gd->cur_serial_dev)
292 ops = serial_get_ops(gd->cur_serial_dev);
294 ops->setbrg(gd->cur_serial_dev, gd->baudrate);
297 int serial_setconfig(uint config)
299 struct dm_serial_ops *ops;
301 if (!gd->cur_serial_dev)
304 ops = serial_get_ops(gd->cur_serial_dev);
306 return ops->setconfig(gd->cur_serial_dev, config);
311 void serial_stdio_init(void)
315 #if defined(CONFIG_DM_STDIO)
317 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
318 static void serial_stub_putc(struct stdio_dev *sdev, const char ch)
320 _serial_putc(sdev->priv, ch);
324 static void serial_stub_puts(struct stdio_dev *sdev, const char *str)
326 _serial_puts(sdev->priv, str);
329 static int serial_stub_getc(struct stdio_dev *sdev)
331 return _serial_getc(sdev->priv);
334 static int serial_stub_tstc(struct stdio_dev *sdev)
336 return _serial_tstc(sdev->priv);
341 * on_baudrate() - Update the actual baudrate when the env var changes
343 * This will check for a valid baudrate and only apply it if valid.
345 static int on_baudrate(const char *name, const char *value, enum env_op op,
353 case env_op_overwrite:
355 * Switch to new baudrate if new baudrate is supported
357 baudrate = simple_strtoul(value, NULL, 10);
359 /* Not actually changing */
360 if (gd->baudrate == baudrate)
363 for (i = 0; i < ARRAY_SIZE(baudrate_table); ++i) {
364 if (baudrate == baudrate_table[i])
367 if (i == ARRAY_SIZE(baudrate_table)) {
368 if ((flags & H_FORCE) == 0)
369 printf("## Baudrate %d bps not supported\n",
373 if ((flags & H_INTERACTIVE) != 0) {
374 printf("## Switch baudrate to %d bps and press ENTER ...\n",
379 gd->baudrate = baudrate;
385 if ((flags & H_INTERACTIVE) != 0)
393 printf("## Baudrate may not be deleted\n");
399 U_BOOT_ENV_CALLBACK(baudrate, on_baudrate);
401 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
402 static int serial_post_probe(struct udevice *dev)
404 struct dm_serial_ops *ops = serial_get_ops(dev);
405 #ifdef CONFIG_DM_STDIO
406 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
407 struct stdio_dev sdev;
411 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
413 ops->setbrg += gd->reloc_off;
415 ops->getc += gd->reloc_off;
417 ops->putc += gd->reloc_off;
419 ops->pending += gd->reloc_off;
421 ops->clear += gd->reloc_off;
423 ops->setconfig += gd->reloc_off;
424 #if CONFIG_POST & CONFIG_SYS_POST_UART
426 ops->loop += gd->reloc_off;
429 /* Set the baud rate */
431 ret = ops->setbrg(dev, gd->baudrate);
436 #ifdef CONFIG_DM_STDIO
437 if (!(gd->flags & GD_FLG_RELOC))
439 memset(&sdev, '\0', sizeof(sdev));
441 strncpy(sdev.name, dev->name, sizeof(sdev.name));
442 sdev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT | DEV_FLAGS_DM;
444 sdev.putc = serial_stub_putc;
445 sdev.puts = serial_stub_puts;
446 sdev.getc = serial_stub_getc;
447 sdev.tstc = serial_stub_tstc;
449 #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
450 /* Allocate the RX buffer */
451 upriv->buf = malloc(CONFIG_SERIAL_RX_BUFFER_SIZE);
454 stdio_register_dev(&sdev, &upriv->sdev);
459 static int serial_pre_remove(struct udevice *dev)
461 #if CONFIG_IS_ENABLED(SYS_STDIO_DEREGISTER)
462 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
464 if (stdio_deregister_dev(upriv->sdev, true))
471 UCLASS_DRIVER(serial) = {
474 .flags = DM_UC_FLAG_SEQ_ALIAS,
475 .post_probe = serial_post_probe,
476 .pre_remove = serial_pre_remove,
477 .per_device_auto_alloc_size = sizeof(struct serial_dev_priv),