1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (c) 2014 The Chromium OS Authors.
8 #include <env_internal.h>
13 #include <stdio_dev.h>
16 #include <dm/device-internal.h>
17 #include <dm/of_access.h>
19 DECLARE_GLOBAL_DATA_PTR;
22 * Table with supported baudrates (defined in config_xyz.h)
24 static const unsigned long baudrate_table[] = CONFIG_SYS_BAUDRATE_TABLE;
26 #if !CONFIG_VAL(SYS_MALLOC_F_LEN)
27 #error "Serial is required before relocation - define CONFIG_$(SPL_)SYS_MALLOC_F_LEN to make this work"
30 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
31 static int serial_check_stdout(const void *blob, struct udevice **devp)
34 const char *str, *p, *name;
37 /* Check for a chosen console */
38 str = fdtdec_get_chosen_prop(blob, "stdout-path");
41 namelen = p ? p - str : strlen(str);
42 node = fdt_path_offset_namelen(blob, str, namelen);
46 * Deal with things like
47 * stdout-path = "serial0:115200n8";
49 * We need to look up the alias and then follow it to
52 name = fdt_get_alias_namelen(blob, str, namelen);
54 node = fdt_path_offset(blob, name);
59 node = fdt_path_offset(blob, "console");
60 if (!uclass_get_device_by_of_offset(UCLASS_SERIAL, node, devp))
64 * If the console is not marked to be bound before relocation, bind it
67 if (node > 0 && !lists_bind_fdt(gd->dm_root, offset_to_ofnode(node),
69 if (!device_probe(*devp))
76 static void serial_find_console_or_panic(void)
78 const void *blob = gd->fdt_blob;
80 #ifdef CONFIG_SERIAL_SEARCH_ALL
84 if (CONFIG_IS_ENABLED(OF_PLATDATA)) {
85 uclass_first_device(UCLASS_SERIAL, &dev);
87 gd->cur_serial_dev = dev;
90 } else if (CONFIG_IS_ENABLED(OF_CONTROL) && blob) {
91 /* Live tree has support for stdout */
92 if (of_live_active()) {
93 struct device_node *np = of_get_stdout();
95 if (np && !uclass_get_device_by_ofnode(UCLASS_SERIAL,
96 np_to_ofnode(np), &dev)) {
97 gd->cur_serial_dev = dev;
101 if (!serial_check_stdout(blob, &dev)) {
102 gd->cur_serial_dev = dev;
107 if (!SPL_BUILD || !CONFIG_IS_ENABLED(OF_CONTROL) || !blob) {
109 * Try to use CONFIG_CONS_INDEX if available (it is numbered
112 * Failing that, get the device with sequence number 0, or in
113 * extremis just the first working serial device we can find.
114 * But we insist on having a console (even if it is silent).
116 #ifdef CONFIG_CONS_INDEX
117 #define INDEX (CONFIG_CONS_INDEX - 1)
122 #ifdef CONFIG_SERIAL_SEARCH_ALL
123 if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
124 !uclass_get_device(UCLASS_SERIAL, INDEX, &dev)) {
125 if (dev->flags & DM_FLAG_ACTIVATED) {
126 gd->cur_serial_dev = dev;
131 /* Search for any working device */
132 for (ret = uclass_first_device_check(UCLASS_SERIAL, &dev);
134 ret = uclass_next_device_check(&dev)) {
136 /* Device did succeed probing */
137 gd->cur_serial_dev = dev;
142 if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
143 !uclass_get_device(UCLASS_SERIAL, INDEX, &dev) ||
144 (!uclass_first_device(UCLASS_SERIAL, &dev) && dev)) {
145 gd->cur_serial_dev = dev;
153 #ifdef CONFIG_REQUIRE_SERIAL_CONSOLE
154 panic_str("No serial driver found");
157 #endif /* CONFIG_SERIAL_PRESENT */
159 /* Called prior to relocation */
160 int serial_init(void)
162 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
163 serial_find_console_or_panic();
164 gd->flags |= GD_FLG_SERIAL_READY;
170 /* Called after relocation */
171 void serial_initialize(void)
176 static void _serial_putc(struct udevice *dev, char ch)
178 struct dm_serial_ops *ops = serial_get_ops(dev);
182 _serial_putc(dev, '\r');
185 err = ops->putc(dev, ch);
186 } while (err == -EAGAIN);
189 static void _serial_puts(struct udevice *dev, const char *str)
192 _serial_putc(dev, *str++);
195 static int __serial_getc(struct udevice *dev)
197 struct dm_serial_ops *ops = serial_get_ops(dev);
201 err = ops->getc(dev);
204 } while (err == -EAGAIN);
206 return err >= 0 ? err : 0;
209 static int __serial_tstc(struct udevice *dev)
211 struct dm_serial_ops *ops = serial_get_ops(dev);
214 return ops->pending(dev, true);
219 #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
220 static int _serial_tstc(struct udevice *dev)
222 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
224 /* Read all available chars into the RX buffer */
225 while (__serial_tstc(dev)) {
226 upriv->buf[upriv->wr_ptr++] = __serial_getc(dev);
227 upriv->wr_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
230 return upriv->rd_ptr != upriv->wr_ptr ? 1 : 0;
233 static int _serial_getc(struct udevice *dev)
235 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
238 if (upriv->rd_ptr == upriv->wr_ptr)
239 return __serial_getc(dev);
241 val = upriv->buf[upriv->rd_ptr++];
242 upriv->rd_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
247 #else /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
249 static int _serial_getc(struct udevice *dev)
251 return __serial_getc(dev);
254 static int _serial_tstc(struct udevice *dev)
256 return __serial_tstc(dev);
258 #endif /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
260 void serial_putc(char ch)
262 if (gd->cur_serial_dev)
263 _serial_putc(gd->cur_serial_dev, ch);
266 void serial_puts(const char *str)
268 if (gd->cur_serial_dev)
269 _serial_puts(gd->cur_serial_dev, str);
272 int serial_getc(void)
274 if (!gd->cur_serial_dev)
277 return _serial_getc(gd->cur_serial_dev);
280 int serial_tstc(void)
282 if (!gd->cur_serial_dev)
285 return _serial_tstc(gd->cur_serial_dev);
288 void serial_setbrg(void)
290 struct dm_serial_ops *ops;
292 if (!gd->cur_serial_dev)
295 ops = serial_get_ops(gd->cur_serial_dev);
297 ops->setbrg(gd->cur_serial_dev, gd->baudrate);
300 int serial_getconfig(struct udevice *dev, uint *config)
302 struct dm_serial_ops *ops;
304 ops = serial_get_ops(dev);
306 return ops->getconfig(dev, config);
311 int serial_setconfig(struct udevice *dev, uint config)
313 struct dm_serial_ops *ops;
315 ops = serial_get_ops(dev);
317 return ops->setconfig(dev, config);
322 int serial_getinfo(struct udevice *dev, struct serial_device_info *info)
324 struct dm_serial_ops *ops;
329 info->baudrate = gd->baudrate;
331 ops = serial_get_ops(dev);
333 return ops->getinfo(dev, info);
338 void serial_stdio_init(void)
342 #if defined(CONFIG_DM_STDIO)
344 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
345 static void serial_stub_putc(struct stdio_dev *sdev, const char ch)
347 _serial_putc(sdev->priv, ch);
351 static void serial_stub_puts(struct stdio_dev *sdev, const char *str)
353 _serial_puts(sdev->priv, str);
356 static int serial_stub_getc(struct stdio_dev *sdev)
358 return _serial_getc(sdev->priv);
361 static int serial_stub_tstc(struct stdio_dev *sdev)
363 return _serial_tstc(sdev->priv);
368 * on_baudrate() - Update the actual baudrate when the env var changes
370 * This will check for a valid baudrate and only apply it if valid.
372 static int on_baudrate(const char *name, const char *value, enum env_op op,
380 case env_op_overwrite:
382 * Switch to new baudrate if new baudrate is supported
384 baudrate = simple_strtoul(value, NULL, 10);
386 /* Not actually changing */
387 if (gd->baudrate == baudrate)
390 for (i = 0; i < ARRAY_SIZE(baudrate_table); ++i) {
391 if (baudrate == baudrate_table[i])
394 if (i == ARRAY_SIZE(baudrate_table)) {
395 if ((flags & H_FORCE) == 0)
396 printf("## Baudrate %d bps not supported\n",
400 if ((flags & H_INTERACTIVE) != 0) {
401 printf("## Switch baudrate to %d bps and press ENTER ...\n",
406 gd->baudrate = baudrate;
412 if ((flags & H_INTERACTIVE) != 0)
420 printf("## Baudrate may not be deleted\n");
426 U_BOOT_ENV_CALLBACK(baudrate, on_baudrate);
428 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
429 static int serial_post_probe(struct udevice *dev)
431 struct dm_serial_ops *ops = serial_get_ops(dev);
432 #ifdef CONFIG_DM_STDIO
433 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
434 struct stdio_dev sdev;
438 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
440 ops->setbrg += gd->reloc_off;
442 ops->getc += gd->reloc_off;
444 ops->putc += gd->reloc_off;
446 ops->pending += gd->reloc_off;
448 ops->clear += gd->reloc_off;
450 ops->getconfig += gd->reloc_off;
452 ops->setconfig += gd->reloc_off;
453 #if CONFIG_POST & CONFIG_SYS_POST_UART
455 ops->loop += gd->reloc_off;
458 ops->getinfo += gd->reloc_off;
460 /* Set the baud rate */
462 ret = ops->setbrg(dev, gd->baudrate);
467 #ifdef CONFIG_DM_STDIO
468 if (!(gd->flags & GD_FLG_RELOC))
470 memset(&sdev, '\0', sizeof(sdev));
472 strncpy(sdev.name, dev->name, sizeof(sdev.name));
473 sdev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT | DEV_FLAGS_DM;
475 sdev.putc = serial_stub_putc;
476 sdev.puts = serial_stub_puts;
477 sdev.getc = serial_stub_getc;
478 sdev.tstc = serial_stub_tstc;
480 #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
481 /* Allocate the RX buffer */
482 upriv->buf = malloc(CONFIG_SERIAL_RX_BUFFER_SIZE);
485 stdio_register_dev(&sdev, &upriv->sdev);
490 static int serial_pre_remove(struct udevice *dev)
492 #if CONFIG_IS_ENABLED(SYS_STDIO_DEREGISTER)
493 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
495 if (stdio_deregister_dev(upriv->sdev, true))
502 UCLASS_DRIVER(serial) = {
505 .flags = DM_UC_FLAG_SEQ_ALIAS,
506 .post_probe = serial_post_probe,
507 .pre_remove = serial_pre_remove,
508 .per_device_auto_alloc_size = sizeof(struct serial_dev_priv),