| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Copyright (c) 2014 The Chromium OS Authors. |
| */ |
| |
| #define LOG_CATEGORY UCLASS_SERIAL |
| |
| #include <common.h> |
| #include <dm.h> |
| #include <env_internal.h> |
| #include <errno.h> |
| #include <malloc.h> |
| #include <os.h> |
| #include <serial.h> |
| #include <stdio_dev.h> |
| #include <watchdog.h> |
| #include <asm/global_data.h> |
| #include <dm/lists.h> |
| #include <dm/device-internal.h> |
| #include <dm/of_access.h> |
| #include <linux/delay.h> |
| |
| DECLARE_GLOBAL_DATA_PTR; |
| |
| /* |
| * Table with supported baudrates (defined in config_xyz.h) |
| */ |
| static const unsigned long baudrate_table[] = CONFIG_SYS_BAUDRATE_TABLE; |
| |
| #if CONFIG_IS_ENABLED(SERIAL_PRESENT) |
| static int serial_check_stdout(const void *blob, struct udevice **devp) |
| { |
| int node = -1; |
| const char *str, *p, *name; |
| int namelen; |
| |
| /* Check for a chosen console */ |
| str = fdtdec_get_chosen_prop(blob, "stdout-path"); |
| if (str) { |
| p = strchr(str, ':'); |
| namelen = p ? p - str : strlen(str); |
| node = fdt_path_offset_namelen(blob, str, namelen); |
| |
| if (node < 0) { |
| /* |
| * Deal with things like |
| * stdout-path = "serial0:115200n8"; |
| * |
| * We need to look up the alias and then follow it to |
| * the correct node. |
| */ |
| name = fdt_get_alias_namelen(blob, str, namelen); |
| if (name) |
| node = fdt_path_offset(blob, name); |
| } |
| } |
| |
| if (node < 0) |
| node = fdt_path_offset(blob, "console"); |
| if (!uclass_get_device_by_of_offset(UCLASS_SERIAL, node, devp)) |
| return 0; |
| |
| /* |
| * If the console is not marked to be bound before relocation, bind it |
| * anyway. |
| */ |
| if (node > 0 && !lists_bind_fdt(gd->dm_root, offset_to_ofnode(node), |
| devp, NULL, false)) { |
| if (!device_probe(*devp)) |
| return 0; |
| } |
| |
| return -ENODEV; |
| } |
| |
| static void serial_find_console_or_panic(void) |
| { |
| const void *blob = gd->fdt_blob; |
| struct udevice *dev; |
| #ifdef CONFIG_SERIAL_SEARCH_ALL |
| int ret; |
| #endif |
| |
| if (CONFIG_IS_ENABLED(OF_PLATDATA)) { |
| uclass_first_device(UCLASS_SERIAL, &dev); |
| if (dev) { |
| gd->cur_serial_dev = dev; |
| return; |
| } |
| } else if (CONFIG_IS_ENABLED(OF_CONTROL) && blob) { |
| /* Live tree has support for stdout */ |
| if (of_live_active()) { |
| struct device_node *np = of_get_stdout(); |
| |
| if (np && !uclass_get_device_by_ofnode(UCLASS_SERIAL, |
| np_to_ofnode(np), &dev)) { |
| gd->cur_serial_dev = dev; |
| return; |
| } |
| } else { |
| if (!serial_check_stdout(blob, &dev)) { |
| gd->cur_serial_dev = dev; |
| return; |
| } |
| } |
| } |
| if (!SPL_BUILD || !CONFIG_IS_ENABLED(OF_CONTROL) || !blob) { |
| /* |
| * Try to use CONFIG_CONS_INDEX if available (it is numbered |
| * from 1!). |
| * |
| * Failing that, get the device with sequence number 0, or in |
| * extremis just the first working serial device we can find. |
| * But we insist on having a console (even if it is silent). |
| */ |
| #ifdef CONFIG_CONS_INDEX |
| #define INDEX (CONFIG_CONS_INDEX - 1) |
| #else |
| #define INDEX 0 |
| #endif |
| |
| #ifdef CONFIG_SERIAL_SEARCH_ALL |
| if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) || |
| !uclass_get_device(UCLASS_SERIAL, INDEX, &dev)) { |
| if (dev_get_flags(dev) & DM_FLAG_ACTIVATED) { |
| gd->cur_serial_dev = dev; |
| return; |
| } |
| } |
| |
| /* Search for any working device */ |
| for (ret = uclass_first_device_check(UCLASS_SERIAL, &dev); |
| dev; |
| ret = uclass_next_device_check(&dev)) { |
| if (!ret) { |
| /* Device did succeed probing */ |
| gd->cur_serial_dev = dev; |
| return; |
| } |
| } |
| #else |
| if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) || |
| !uclass_get_device(UCLASS_SERIAL, INDEX, &dev) || |
| (!uclass_first_device(UCLASS_SERIAL, &dev) && dev)) { |
| gd->cur_serial_dev = dev; |
| return; |
| } |
| #endif |
| |
| #undef INDEX |
| } |
| |
| #ifdef CONFIG_REQUIRE_SERIAL_CONSOLE |
| panic_str("No serial driver found"); |
| #endif |
| } |
| #endif /* CONFIG_SERIAL_PRESENT */ |
| |
| /* Called prior to relocation */ |
| int serial_init(void) |
| { |
| #if CONFIG_IS_ENABLED(SERIAL_PRESENT) |
| serial_find_console_or_panic(); |
| gd->flags |= GD_FLG_SERIAL_READY; |
| serial_setbrg(); |
| #endif |
| |
| return 0; |
| } |
| |
| /* Called after relocation */ |
| int serial_initialize(void) |
| { |
| /* Scanning uclass to probe devices */ |
| if (IS_ENABLED(CONFIG_SERIAL_PROBE_ALL)) { |
| int ret; |
| |
| ret = uclass_probe_all(UCLASS_SERIAL); |
| if (ret) |
| return ret; |
| } |
| |
| return serial_init(); |
| } |
| |
| static void _serial_putc(struct udevice *dev, char ch) |
| { |
| struct dm_serial_ops *ops = serial_get_ops(dev); |
| int err; |
| |
| if (ch == '\n') |
| _serial_putc(dev, '\r'); |
| |
| do { |
| err = ops->putc(dev, ch); |
| } while (err == -EAGAIN); |
| } |
| |
| static void _serial_puts(struct udevice *dev, const char *str) |
| { |
| while (*str) |
| _serial_putc(dev, *str++); |
| } |
| |
| static int __serial_getc(struct udevice *dev) |
| { |
| struct dm_serial_ops *ops = serial_get_ops(dev); |
| int err; |
| |
| do { |
| err = ops->getc(dev); |
| if (err == -EAGAIN) |
| WATCHDOG_RESET(); |
| } while (err == -EAGAIN); |
| |
| return err >= 0 ? err : 0; |
| } |
| |
| static int __serial_tstc(struct udevice *dev) |
| { |
| struct dm_serial_ops *ops = serial_get_ops(dev); |
| |
| if (ops->pending) |
| return ops->pending(dev, true); |
| |
| return 1; |
| } |
| |
| #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) |
| static int _serial_tstc(struct udevice *dev) |
| { |
| struct serial_dev_priv *upriv = dev_get_uclass_priv(dev); |
| |
| /* Read all available chars into the RX buffer */ |
| while (__serial_tstc(dev)) { |
| upriv->buf[upriv->wr_ptr++] = __serial_getc(dev); |
| upriv->wr_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE; |
| } |
| |
| return upriv->rd_ptr != upriv->wr_ptr ? 1 : 0; |
| } |
| |
| static int _serial_getc(struct udevice *dev) |
| { |
| struct serial_dev_priv *upriv = dev_get_uclass_priv(dev); |
| char val; |
| |
| if (upriv->rd_ptr == upriv->wr_ptr) |
| return __serial_getc(dev); |
| |
| val = upriv->buf[upriv->rd_ptr++]; |
| upriv->rd_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE; |
| |
| return val; |
| } |
| |
| #else /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */ |
| |
| static int _serial_getc(struct udevice *dev) |
| { |
| return __serial_getc(dev); |
| } |
| |
| static int _serial_tstc(struct udevice *dev) |
| { |
| return __serial_tstc(dev); |
| } |
| #endif /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */ |
| |
| void serial_putc(char ch) |
| { |
| if (gd->cur_serial_dev) |
| _serial_putc(gd->cur_serial_dev, ch); |
| } |
| |
| void serial_puts(const char *str) |
| { |
| if (gd->cur_serial_dev) |
| _serial_puts(gd->cur_serial_dev, str); |
| } |
| |
| int serial_getc(void) |
| { |
| if (!gd->cur_serial_dev) |
| return 0; |
| |
| return _serial_getc(gd->cur_serial_dev); |
| } |
| |
| int serial_tstc(void) |
| { |
| if (!gd->cur_serial_dev) |
| return 0; |
| |
| return _serial_tstc(gd->cur_serial_dev); |
| } |
| |
| void serial_setbrg(void) |
| { |
| struct dm_serial_ops *ops; |
| |
| if (!gd->cur_serial_dev) |
| return; |
| |
| ops = serial_get_ops(gd->cur_serial_dev); |
| if (ops->setbrg) |
| ops->setbrg(gd->cur_serial_dev, gd->baudrate); |
| } |
| |
| int serial_getconfig(struct udevice *dev, uint *config) |
| { |
| struct dm_serial_ops *ops; |
| |
| ops = serial_get_ops(dev); |
| if (ops->getconfig) |
| return ops->getconfig(dev, config); |
| |
| return 0; |
| } |
| |
| int serial_setconfig(struct udevice *dev, uint config) |
| { |
| struct dm_serial_ops *ops; |
| |
| ops = serial_get_ops(dev); |
| if (ops->setconfig) |
| return ops->setconfig(dev, config); |
| |
| return 0; |
| } |
| |
| int serial_getinfo(struct udevice *dev, struct serial_device_info *info) |
| { |
| struct dm_serial_ops *ops; |
| |
| if (!info) |
| return -EINVAL; |
| |
| info->baudrate = gd->baudrate; |
| |
| ops = serial_get_ops(dev); |
| if (ops->getinfo) |
| return ops->getinfo(dev, info); |
| |
| return -EINVAL; |
| } |
| |
| void serial_stdio_init(void) |
| { |
| } |
| |
| #if defined(CONFIG_DM_STDIO) |
| |
| #if CONFIG_IS_ENABLED(SERIAL_PRESENT) |
| static void serial_stub_putc(struct stdio_dev *sdev, const char ch) |
| { |
| _serial_putc(sdev->priv, ch); |
| } |
| #endif |
| |
| static void serial_stub_puts(struct stdio_dev *sdev, const char *str) |
| { |
| _serial_puts(sdev->priv, str); |
| } |
| |
| static int serial_stub_getc(struct stdio_dev *sdev) |
| { |
| return _serial_getc(sdev->priv); |
| } |
| |
| static int serial_stub_tstc(struct stdio_dev *sdev) |
| { |
| return _serial_tstc(sdev->priv); |
| } |
| #endif |
| |
| /** |
| * on_baudrate() - Update the actual baudrate when the env var changes |
| * |
| * This will check for a valid baudrate and only apply it if valid. |
| */ |
| static int on_baudrate(const char *name, const char *value, enum env_op op, |
| int flags) |
| { |
| int i; |
| int baudrate; |
| |
| switch (op) { |
| case env_op_create: |
| case env_op_overwrite: |
| /* |
| * Switch to new baudrate if new baudrate is supported |
| */ |
| baudrate = dectoul(value, NULL); |
| |
| /* Not actually changing */ |
| if (gd->baudrate == baudrate) |
| return 0; |
| |
| for (i = 0; i < ARRAY_SIZE(baudrate_table); ++i) { |
| if (baudrate == baudrate_table[i]) |
| break; |
| } |
| if (i == ARRAY_SIZE(baudrate_table)) { |
| if ((flags & H_FORCE) == 0) |
| printf("## Baudrate %d bps not supported\n", |
| baudrate); |
| return 1; |
| } |
| if ((flags & H_INTERACTIVE) != 0) { |
| printf("## Switch baudrate to %d bps and press ENTER ...\n", |
| baudrate); |
| udelay(50000); |
| } |
| |
| gd->baudrate = baudrate; |
| |
| serial_setbrg(); |
| |
| udelay(50000); |
| |
| if ((flags & H_INTERACTIVE) != 0) |
| while (1) { |
| if (getchar() == '\r') |
| break; |
| } |
| |
| return 0; |
| case env_op_delete: |
| printf("## Baudrate may not be deleted\n"); |
| return 1; |
| default: |
| return 0; |
| } |
| } |
| U_BOOT_ENV_CALLBACK(baudrate, on_baudrate); |
| |
| #if CONFIG_IS_ENABLED(SERIAL_PRESENT) |
| static int serial_post_probe(struct udevice *dev) |
| { |
| struct dm_serial_ops *ops = serial_get_ops(dev); |
| #ifdef CONFIG_DM_STDIO |
| struct serial_dev_priv *upriv = dev_get_uclass_priv(dev); |
| struct stdio_dev sdev; |
| #endif |
| int ret; |
| |
| #if defined(CONFIG_NEEDS_MANUAL_RELOC) |
| if (ops->setbrg) |
| ops->setbrg += gd->reloc_off; |
| if (ops->getc) |
| ops->getc += gd->reloc_off; |
| if (ops->putc) |
| ops->putc += gd->reloc_off; |
| if (ops->pending) |
| ops->pending += gd->reloc_off; |
| if (ops->clear) |
| ops->clear += gd->reloc_off; |
| if (ops->getconfig) |
| ops->getconfig += gd->reloc_off; |
| if (ops->setconfig) |
| ops->setconfig += gd->reloc_off; |
| #if CONFIG_POST & CONFIG_SYS_POST_UART |
| if (ops->loop) |
| ops->loop += gd->reloc_off; |
| #endif |
| if (ops->getinfo) |
| ops->getinfo += gd->reloc_off; |
| #endif |
| /* Set the baud rate */ |
| if (ops->setbrg) { |
| ret = ops->setbrg(dev, gd->baudrate); |
| if (ret) |
| return ret; |
| } |
| |
| #ifdef CONFIG_DM_STDIO |
| if (!(gd->flags & GD_FLG_RELOC)) |
| return 0; |
| memset(&sdev, '\0', sizeof(sdev)); |
| |
| strncpy(sdev.name, dev->name, sizeof(sdev.name)); |
| sdev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT | DEV_FLAGS_DM; |
| sdev.priv = dev; |
| sdev.putc = serial_stub_putc; |
| sdev.puts = serial_stub_puts; |
| sdev.getc = serial_stub_getc; |
| sdev.tstc = serial_stub_tstc; |
| |
| #if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) |
| /* Allocate the RX buffer */ |
| upriv->buf = malloc(CONFIG_SERIAL_RX_BUFFER_SIZE); |
| #endif |
| |
| stdio_register_dev(&sdev, &upriv->sdev); |
| #endif |
| return 0; |
| } |
| |
| static int serial_pre_remove(struct udevice *dev) |
| { |
| #if CONFIG_IS_ENABLED(SYS_STDIO_DEREGISTER) |
| struct serial_dev_priv *upriv = dev_get_uclass_priv(dev); |
| |
| if (stdio_deregister_dev(upriv->sdev, true)) |
| return -EPERM; |
| #endif |
| |
| return 0; |
| } |
| |
| UCLASS_DRIVER(serial) = { |
| .id = UCLASS_SERIAL, |
| .name = "serial", |
| .flags = DM_UC_FLAG_SEQ_ALIAS, |
| .post_probe = serial_post_probe, |
| .pre_remove = serial_pre_remove, |
| .per_device_auto = sizeof(struct serial_dev_priv), |
| }; |
| #endif |