2 * Copyright (c) 2014 The Chromium OS Authors.
4 * SPDX-License-Identifier: GPL-2.0+
9 #include <environment.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 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;
79 if (CONFIG_IS_ENABLED(OF_PLATDATA)) {
80 uclass_first_device(UCLASS_SERIAL, &dev);
82 gd->cur_serial_dev = dev;
85 } else if (CONFIG_IS_ENABLED(OF_CONTROL) && blob) {
86 /* Live tree has support for stdout */
87 if (of_live_active()) {
88 struct device_node *np = of_get_stdout();
90 if (np && !uclass_get_device_by_ofnode(UCLASS_SERIAL,
91 np_to_ofnode(np), &dev)) {
92 gd->cur_serial_dev = dev;
96 if (!serial_check_stdout(blob, &dev)) {
97 gd->cur_serial_dev = dev;
102 if (!SPL_BUILD || !CONFIG_IS_ENABLED(OF_CONTROL) || !blob) {
104 * Try to use CONFIG_CONS_INDEX if available (it is numbered
107 * Failing that, get the device with sequence number 0, or in
108 * extremis just the first working serial device we can find.
109 * But we insist on having a console (even if it is silent).
111 #ifdef CONFIG_CONS_INDEX
112 #define INDEX (CONFIG_CONS_INDEX - 1)
116 if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
117 !uclass_get_device(UCLASS_SERIAL, INDEX, &dev)) {
118 if (dev->flags & DM_FLAG_ACTIVATED) {
119 gd->cur_serial_dev = dev;
124 /* Search for any working device */
125 for (ret = uclass_first_device_check(UCLASS_SERIAL, &dev);
127 ret = uclass_next_device_check(&dev)) {
129 /* Device did succeed probing */
130 gd->cur_serial_dev = dev;
137 #ifdef CONFIG_REQUIRE_SERIAL_CONSOLE
138 panic_str("No serial driver found");
142 /* Called prior to relocation */
143 int serial_init(void)
145 serial_find_console_or_panic();
146 gd->flags |= GD_FLG_SERIAL_READY;
151 /* Called after relocation */
152 void serial_initialize(void)
157 static void _serial_putc(struct udevice *dev, char ch)
159 struct dm_serial_ops *ops = serial_get_ops(dev);
163 _serial_putc(dev, '\r');
166 err = ops->putc(dev, ch);
167 } while (err == -EAGAIN);
170 static void _serial_puts(struct udevice *dev, const char *str)
173 _serial_putc(dev, *str++);
176 static int __serial_getc(struct udevice *dev)
178 struct dm_serial_ops *ops = serial_get_ops(dev);
182 err = ops->getc(dev);
185 } while (err == -EAGAIN);
187 return err >= 0 ? err : 0;
190 static int __serial_tstc(struct udevice *dev)
192 struct dm_serial_ops *ops = serial_get_ops(dev);
195 return ops->pending(dev, true);
200 #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
201 static int _serial_tstc(struct udevice *dev)
203 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
205 /* Read all available chars into the RX buffer */
206 while (__serial_tstc(dev)) {
207 upriv->buf[upriv->wr_ptr++] = __serial_getc(dev);
208 upriv->wr_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
211 return upriv->rd_ptr != upriv->wr_ptr ? 1 : 0;
214 static int _serial_getc(struct udevice *dev)
216 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
219 val = upriv->buf[upriv->rd_ptr++];
220 upriv->rd_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
225 #else /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
227 static int _serial_getc(struct udevice *dev)
229 return __serial_getc(dev);
232 static int _serial_tstc(struct udevice *dev)
234 return __serial_tstc(dev);
236 #endif /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
238 void serial_putc(char ch)
240 if (gd->cur_serial_dev)
241 _serial_putc(gd->cur_serial_dev, ch);
244 void serial_puts(const char *str)
246 if (gd->cur_serial_dev)
247 _serial_puts(gd->cur_serial_dev, str);
250 int serial_getc(void)
252 if (!gd->cur_serial_dev)
255 return _serial_getc(gd->cur_serial_dev);
258 int serial_tstc(void)
260 if (!gd->cur_serial_dev)
263 return _serial_tstc(gd->cur_serial_dev);
266 void serial_setbrg(void)
268 struct dm_serial_ops *ops;
270 if (!gd->cur_serial_dev)
273 ops = serial_get_ops(gd->cur_serial_dev);
275 ops->setbrg(gd->cur_serial_dev, gd->baudrate);
278 void serial_stdio_init(void)
282 #if defined(CONFIG_DM_STDIO)
284 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
285 static void serial_stub_putc(struct stdio_dev *sdev, const char ch)
287 _serial_putc(sdev->priv, ch);
291 static void serial_stub_puts(struct stdio_dev *sdev, const char *str)
293 _serial_puts(sdev->priv, str);
296 static int serial_stub_getc(struct stdio_dev *sdev)
298 return _serial_getc(sdev->priv);
301 static int serial_stub_tstc(struct stdio_dev *sdev)
303 return _serial_tstc(sdev->priv);
308 * on_baudrate() - Update the actual baudrate when the env var changes
310 * This will check for a valid baudrate and only apply it if valid.
312 static int on_baudrate(const char *name, const char *value, enum env_op op,
320 case env_op_overwrite:
322 * Switch to new baudrate if new baudrate is supported
324 baudrate = simple_strtoul(value, NULL, 10);
326 /* Not actually changing */
327 if (gd->baudrate == baudrate)
330 for (i = 0; i < ARRAY_SIZE(baudrate_table); ++i) {
331 if (baudrate == baudrate_table[i])
334 if (i == ARRAY_SIZE(baudrate_table)) {
335 if ((flags & H_FORCE) == 0)
336 printf("## Baudrate %d bps not supported\n",
340 if ((flags & H_INTERACTIVE) != 0) {
341 printf("## Switch baudrate to %d bps and press ENTER ...\n",
346 gd->baudrate = baudrate;
352 if ((flags & H_INTERACTIVE) != 0)
360 printf("## Baudrate may not be deleted\n");
366 U_BOOT_ENV_CALLBACK(baudrate, on_baudrate);
368 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
369 static int serial_post_probe(struct udevice *dev)
371 struct dm_serial_ops *ops = serial_get_ops(dev);
372 #ifdef CONFIG_DM_STDIO
373 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
374 struct stdio_dev sdev;
378 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
380 ops->setbrg += gd->reloc_off;
382 ops->getc += gd->reloc_off;
384 ops->putc += gd->reloc_off;
386 ops->pending += gd->reloc_off;
388 ops->clear += gd->reloc_off;
389 #if CONFIG_POST & CONFIG_SYS_POST_UART
391 ops->loop += gd->reloc_off
394 /* Set the baud rate */
396 ret = ops->setbrg(dev, gd->baudrate);
401 #ifdef CONFIG_DM_STDIO
402 if (!(gd->flags & GD_FLG_RELOC))
404 memset(&sdev, '\0', sizeof(sdev));
406 strncpy(sdev.name, dev->name, sizeof(sdev.name));
407 sdev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT | DEV_FLAGS_DM;
409 sdev.putc = serial_stub_putc;
410 sdev.puts = serial_stub_puts;
411 sdev.getc = serial_stub_getc;
412 sdev.tstc = serial_stub_tstc;
414 #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
415 /* Allocate the RX buffer */
416 upriv->buf = malloc(CONFIG_SERIAL_RX_BUFFER_SIZE);
419 stdio_register_dev(&sdev, &upriv->sdev);
424 static int serial_pre_remove(struct udevice *dev)
426 #if CONFIG_IS_ENABLED(SYS_STDIO_DEREGISTER)
427 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
429 if (stdio_deregister_dev(upriv->sdev, true))
436 UCLASS_DRIVER(serial) = {
439 .flags = DM_UC_FLAG_SEQ_ALIAS,
440 .post_probe = serial_post_probe,
441 .pre_remove = serial_pre_remove,
442 .per_device_auto_alloc_size = sizeof(struct serial_dev_priv),