Coreboot can provide information about the serial device in use on a platform. Add a driver that uses this information to produce a working UART.
Signed-off-by: Simon Glass sjg@chromium.org Reviewed-by: Bin Meng bmeng.cn@gmail.com ---
Changes in v3: None Changes in v2: None
drivers/serial/Kconfig | 11 ++++++++ drivers/serial/Makefile | 1 + drivers/serial/serial_coreboot.c | 46 ++++++++++++++++++++++++++++++++ 3 files changed, 58 insertions(+) create mode 100644 drivers/serial/serial_coreboot.c
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 472a9f0929..c403c2fc25 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -539,6 +539,17 @@ config BCM6345_SERIAL help Select this to enable UART on BCM6345 SoCs.
+config COREBOOT_SERIAL + bool "Coreboot UART support" + depends on DM_SERIAL + default y if SYS_COREBOOT + select SYS_NS16550 + help + Select this to enable a ns16550-style UART where the platform data + comes from the coreboot 'sysinfo' tables. This allows U-Boot to have + a serial console on any platform without needing to change the + device tree, etc. + config FSL_LINFLEXUART bool "Freescale Linflex UART support" depends on DM_SERIAL diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index 06ee30697d..76b1811510 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_AR933X_UART) += serial_ar933x.o obj-$(CONFIG_ARM_DCC) += arm_dcc.o obj-$(CONFIG_ATMEL_USART) += atmel_usart.o obj-$(CONFIG_BCM6345_SERIAL) += serial_bcm6345.o +obj-$(CONFIG_COREBOOT_SERIAL) += serial_coreboot.o obj-$(CONFIG_EFI_APP) += serial_efi.o obj-$(CONFIG_LPC32XX_HSUART) += lpc32xx_hsuart.o obj-$(CONFIG_MCFUART) += mcfuart.o diff --git a/drivers/serial/serial_coreboot.c b/drivers/serial/serial_coreboot.c new file mode 100644 index 0000000000..ccab347514 --- /dev/null +++ b/drivers/serial/serial_coreboot.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * UART support for U-Boot when launched from Coreboot + * + * Copyright 2019 Google LLC + */ + +#include <common.h> +#include <dm.h> +#include <ns16550.h> +#include <serial.h> +#include <asm/arch/sysinfo.h> + +static int coreboot_ofdata_to_platdata(struct udevice *dev) +{ + struct ns16550_platdata *plat = dev_get_platdata(dev); + struct cb_serial *cb_info = lib_sysinfo.serial; + + plat->base = cb_info->baseaddr; + plat->reg_shift = cb_info->regwidth == 4 ? 2 : 0; + plat->reg_width = cb_info->regwidth; + plat->clock = cb_info->input_hertz; + plat->fcr = UART_FCR_DEFVAL; + plat->flags = 0; + if (cb_info->type == CB_SERIAL_TYPE_IO_MAPPED) + plat->flags |= NS16550_FLAG_IO; + + return 0; +} + +static const struct udevice_id coreboot_serial_ids[] = { + { .compatible = "coreboot-serial" }, + { }, +}; + +U_BOOT_DRIVER(coreboot_uart) = { + .name = "coreboot_uart", + .id = UCLASS_SERIAL, + .of_match = coreboot_serial_ids, + .priv_auto_alloc_size = sizeof(struct NS16550), + .platdata_auto_alloc_size = sizeof(struct ns16550_platdata), + .ofdata_to_platdata = coreboot_ofdata_to_platdata, + .probe = ns16550_serial_probe, + .ops = &ns16550_serial_ops, + .flags = DM_FLAG_PRE_RELOC, +};