| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Copyright (c) 2015 Google, Inc |
| * Written by Simon Glass <sjg@chromium.org> |
| */ |
| |
| #include <common.h> |
| #include <debug_uart.h> |
| #include <dm.h> |
| #include <efi.h> |
| #include <efi_api.h> |
| #include <errno.h> |
| #include <fdtdec.h> |
| #include <log.h> |
| #include <linux/compiler.h> |
| #include <asm/io.h> |
| #include <serial.h> |
| |
| /* Information about the efi console */ |
| struct serial_efi_priv { |
| struct efi_simple_text_input_protocol *con_in; |
| struct efi_simple_text_output_protocol *con_out; |
| struct efi_input_key key; |
| bool have_key; |
| }; |
| |
| int serial_efi_setbrg(struct udevice *dev, int baudrate) |
| { |
| return 0; |
| } |
| |
| static int serial_efi_get_key(struct serial_efi_priv *priv) |
| { |
| int ret; |
| |
| if (priv->have_key) |
| return 0; |
| ret = priv->con_in->read_key_stroke(priv->con_in, &priv->key); |
| if (ret == EFI_NOT_READY) |
| return -EAGAIN; |
| else if (ret != EFI_SUCCESS) |
| return -EIO; |
| |
| priv->have_key = true; |
| |
| return 0; |
| } |
| |
| static int serial_efi_getc(struct udevice *dev) |
| { |
| struct serial_efi_priv *priv = dev_get_priv(dev); |
| int ret, ch; |
| |
| ret = serial_efi_get_key(priv); |
| if (ret) |
| return ret; |
| |
| priv->have_key = false; |
| ch = priv->key.unicode_char; |
| |
| /* |
| * Unicode char 8 (for backspace) is never returned. Instead we get a |
| * key scan code of 8. Handle this so that backspace works correctly |
| * in the U-Boot command line. |
| */ |
| if (!ch && priv->key.scan_code == 8) |
| ch = 8; |
| debug(" [%x %x %x] ", ch, priv->key.unicode_char, priv->key.scan_code); |
| |
| return ch; |
| } |
| |
| static int serial_efi_putc(struct udevice *dev, const char ch) |
| { |
| struct serial_efi_priv *priv = dev_get_priv(dev); |
| uint16_t ucode[2]; |
| int ret; |
| |
| ucode[0] = ch; |
| ucode[1] = '\0'; |
| ret = priv->con_out->output_string(priv->con_out, ucode); |
| if (ret) |
| return -EIO; |
| |
| return 0; |
| } |
| |
| static int serial_efi_pending(struct udevice *dev, bool input) |
| { |
| struct serial_efi_priv *priv = dev_get_priv(dev); |
| int ret; |
| |
| /* We assume that EFI will stall if its output buffer fills up */ |
| if (!input) |
| return 0; |
| |
| ret = serial_efi_get_key(priv); |
| if (ret == -EAGAIN) |
| return 0; |
| else if (ret) |
| return ret; |
| |
| return 1; |
| } |
| |
| /* |
| * There is nothing to init here since the EFI console is already running by |
| * the time we enter U-Boot. |
| */ |
| static inline void _debug_uart_init(void) |
| { |
| } |
| |
| static inline void _debug_uart_putc(int ch) |
| { |
| struct efi_system_table *sys_table = efi_get_sys_table(); |
| uint16_t ucode[2]; |
| |
| ucode[0] = ch; |
| ucode[1] = '\0'; |
| sys_table->con_out->output_string(sys_table->con_out, ucode); |
| } |
| |
| DEBUG_UART_FUNCS |
| |
| static int serial_efi_probe(struct udevice *dev) |
| { |
| struct efi_system_table *table = efi_get_sys_table(); |
| struct serial_efi_priv *priv = dev_get_priv(dev); |
| |
| priv->con_in = table->con_in; |
| priv->con_out = table->con_out; |
| |
| return 0; |
| } |
| |
| static const struct dm_serial_ops serial_efi_ops = { |
| .putc = serial_efi_putc, |
| .getc = serial_efi_getc, |
| .pending = serial_efi_pending, |
| .setbrg = serial_efi_setbrg, |
| }; |
| |
| static const struct udevice_id serial_efi_ids[] = { |
| { .compatible = "efi,uart" }, |
| { } |
| }; |
| |
| U_BOOT_DRIVER(serial_efi) = { |
| .name = "serial_efi", |
| .id = UCLASS_SERIAL, |
| .of_match = serial_efi_ids, |
| .priv_auto_alloc_size = sizeof(struct serial_efi_priv), |
| .probe = serial_efi_probe, |
| .ops = &serial_efi_ops, |
| }; |