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;
78 if (CONFIG_IS_ENABLED(OF_PLATDATA)) {
79 uclass_first_device(UCLASS_SERIAL, &dev);
81 gd->cur_serial_dev = dev;
84 } else if (CONFIG_IS_ENABLED(OF_CONTROL) && blob) {
85 /* Live tree has support for stdout */
86 if (of_live_active()) {
87 struct device_node *np = of_get_stdout();
89 if (np && !uclass_get_device_by_ofnode(UCLASS_SERIAL,
90 np_to_ofnode(np), &dev)) {
91 gd->cur_serial_dev = dev;
95 if (!serial_check_stdout(blob, &dev)) {
96 gd->cur_serial_dev = dev;
101 if (!SPL_BUILD || !CONFIG_IS_ENABLED(OF_CONTROL) || !blob) {
103 * Try to use CONFIG_CONS_INDEX if available (it is numbered
106 * Failing that, get the device with sequence number 0, or in
107 * extremis just the first serial device we can find. But we
108 * insist on having a console (even if it is silent).
110 #ifdef CONFIG_CONS_INDEX
111 #define INDEX (CONFIG_CONS_INDEX - 1)
115 if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
116 !uclass_get_device(UCLASS_SERIAL, INDEX, &dev) ||
117 (!uclass_first_device(UCLASS_SERIAL, &dev) && dev)) {
118 gd->cur_serial_dev = dev;
124 #ifdef CONFIG_REQUIRE_SERIAL_CONSOLE
125 panic_str("No serial driver found");
129 /* Called prior to relocation */
130 int serial_init(void)
132 serial_find_console_or_panic();
133 gd->flags |= GD_FLG_SERIAL_READY;
138 /* Called after relocation */
139 void serial_initialize(void)
144 static void _serial_putc(struct udevice *dev, char ch)
146 struct dm_serial_ops *ops = serial_get_ops(dev);
150 _serial_putc(dev, '\r');
153 err = ops->putc(dev, ch);
154 } while (err == -EAGAIN);
157 static void _serial_puts(struct udevice *dev, const char *str)
160 _serial_putc(dev, *str++);
163 static int __serial_getc(struct udevice *dev)
165 struct dm_serial_ops *ops = serial_get_ops(dev);
169 err = ops->getc(dev);
172 } while (err == -EAGAIN);
174 return err >= 0 ? err : 0;
177 static int __serial_tstc(struct udevice *dev)
179 struct dm_serial_ops *ops = serial_get_ops(dev);
182 return ops->pending(dev, true);
187 #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
188 static int _serial_tstc(struct udevice *dev)
190 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
192 /* Read all available chars into the RX buffer */
193 while (__serial_tstc(dev)) {
194 upriv->buf[upriv->wr_ptr++] = __serial_getc(dev);
195 upriv->wr_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
198 return upriv->rd_ptr != upriv->wr_ptr ? 1 : 0;
201 static int _serial_getc(struct udevice *dev)
203 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
206 val = upriv->buf[upriv->rd_ptr++];
207 upriv->rd_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
212 #else /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
214 static int _serial_getc(struct udevice *dev)
216 return __serial_getc(dev);
219 static int _serial_tstc(struct udevice *dev)
221 return __serial_tstc(dev);
223 #endif /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
225 void serial_putc(char ch)
227 if (gd->cur_serial_dev)
228 _serial_putc(gd->cur_serial_dev, ch);
231 void serial_puts(const char *str)
233 if (gd->cur_serial_dev)
234 _serial_puts(gd->cur_serial_dev, str);
237 int serial_getc(void)
239 if (!gd->cur_serial_dev)
242 return _serial_getc(gd->cur_serial_dev);
245 int serial_tstc(void)
247 if (!gd->cur_serial_dev)
250 return _serial_tstc(gd->cur_serial_dev);
253 void serial_setbrg(void)
255 struct dm_serial_ops *ops;
257 if (!gd->cur_serial_dev)
260 ops = serial_get_ops(gd->cur_serial_dev);
262 ops->setbrg(gd->cur_serial_dev, gd->baudrate);
265 void serial_stdio_init(void)
269 #if defined(CONFIG_DM_STDIO)
271 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
272 static void serial_stub_putc(struct stdio_dev *sdev, const char ch)
274 _serial_putc(sdev->priv, ch);
278 static void serial_stub_puts(struct stdio_dev *sdev, const char *str)
280 _serial_puts(sdev->priv, str);
283 static int serial_stub_getc(struct stdio_dev *sdev)
285 return _serial_getc(sdev->priv);
288 static int serial_stub_tstc(struct stdio_dev *sdev)
290 return _serial_tstc(sdev->priv);
295 * on_baudrate() - Update the actual baudrate when the env var changes
297 * This will check for a valid baudrate and only apply it if valid.
299 static int on_baudrate(const char *name, const char *value, enum env_op op,
307 case env_op_overwrite:
309 * Switch to new baudrate if new baudrate is supported
311 baudrate = simple_strtoul(value, NULL, 10);
313 /* Not actually changing */
314 if (gd->baudrate == baudrate)
317 for (i = 0; i < ARRAY_SIZE(baudrate_table); ++i) {
318 if (baudrate == baudrate_table[i])
321 if (i == ARRAY_SIZE(baudrate_table)) {
322 if ((flags & H_FORCE) == 0)
323 printf("## Baudrate %d bps not supported\n",
327 if ((flags & H_INTERACTIVE) != 0) {
328 printf("## Switch baudrate to %d bps and press ENTER ...\n",
333 gd->baudrate = baudrate;
339 if ((flags & H_INTERACTIVE) != 0)
347 printf("## Baudrate may not be deleted\n");
353 U_BOOT_ENV_CALLBACK(baudrate, on_baudrate);
355 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
356 static int serial_post_probe(struct udevice *dev)
358 struct dm_serial_ops *ops = serial_get_ops(dev);
359 #ifdef CONFIG_DM_STDIO
360 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
361 struct stdio_dev sdev;
365 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
367 ops->setbrg += gd->reloc_off;
369 ops->getc += gd->reloc_off;
371 ops->putc += gd->reloc_off;
373 ops->pending += gd->reloc_off;
375 ops->clear += gd->reloc_off;
376 #if CONFIG_POST & CONFIG_SYS_POST_UART
378 ops->loop += gd->reloc_off
381 /* Set the baud rate */
383 ret = ops->setbrg(dev, gd->baudrate);
388 #ifdef CONFIG_DM_STDIO
389 if (!(gd->flags & GD_FLG_RELOC))
391 memset(&sdev, '\0', sizeof(sdev));
393 strncpy(sdev.name, dev->name, sizeof(sdev.name));
394 sdev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT | DEV_FLAGS_DM;
396 sdev.putc = serial_stub_putc;
397 sdev.puts = serial_stub_puts;
398 sdev.getc = serial_stub_getc;
399 sdev.tstc = serial_stub_tstc;
401 #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
402 /* Allocate the RX buffer */
403 upriv->buf = malloc(CONFIG_SERIAL_RX_BUFFER_SIZE);
406 stdio_register_dev(&sdev, &upriv->sdev);
411 static int serial_pre_remove(struct udevice *dev)
413 #if CONFIG_IS_ENABLED(SYS_STDIO_DEREGISTER)
414 struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
416 if (stdio_deregister_dev(upriv->sdev, true))
423 UCLASS_DRIVER(serial) = {
426 .flags = DM_UC_FLAG_SEQ_ALIAS,
427 .post_probe = serial_post_probe,
428 .pre_remove = serial_pre_remove,
429 .per_device_auto_alloc_size = sizeof(struct serial_dev_priv),