1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * UART support for U-Boot when launched from Coreboot
4 *
5 * Copyright 2019 Google LLC
6 */
7
8 #include <common.h>
9 #include <dm.h>
10 #include <ns16550.h>
11 #include <serial.h>
12 #include <asm/arch/sysinfo.h>
13
coreboot_of_to_plat(struct udevice * dev)14 static int coreboot_of_to_plat(struct udevice *dev)
15 {
16 struct ns16550_plat *plat = dev_get_plat(dev);
17 struct cb_serial *cb_info = lib_sysinfo.serial;
18
19 plat->base = cb_info->baseaddr;
20 plat->reg_shift = cb_info->regwidth == 4 ? 2 : 0;
21 plat->reg_width = cb_info->regwidth;
22 plat->clock = cb_info->input_hertz;
23 plat->fcr = UART_FCR_DEFVAL;
24 plat->flags = 0;
25 if (cb_info->type == CB_SERIAL_TYPE_IO_MAPPED)
26 plat->flags |= NS16550_FLAG_IO;
27
28 return 0;
29 }
30
31 static const struct udevice_id coreboot_serial_ids[] = {
32 { .compatible = "coreboot-serial" },
33 { },
34 };
35
36 U_BOOT_DRIVER(coreboot_uart) = {
37 .name = "coreboot_uart",
38 .id = UCLASS_SERIAL,
39 .of_match = coreboot_serial_ids,
40 .priv_auto = sizeof(struct ns16550),
41 .plat_auto = sizeof(struct ns16550_plat),
42 .of_to_plat = coreboot_of_to_plat,
43 .probe = ns16550_serial_probe,
44 .ops = &ns16550_serial_ops,
45 .flags = DM_FLAG_PRE_RELOC,
46 };
47