From c77bf3607a0f0180aa674b58cfa76633215bb42f Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Fri, 24 Nov 2023 12:39:03 +0530 Subject: tty/serial: Add RISC-V SBI debug console based earlycon We extend the existing RISC-V SBI earlycon support to use the new RISC-V SBI debug console extension. Signed-off-by: Anup Patel Reviewed-by: Andrew Jones Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20231124070905.1043092-4-apatel@ventanamicro.com Signed-off-by: Palmer Dabbelt --- drivers/tty/serial/Kconfig | 2 +- drivers/tty/serial/earlycon-riscv-sbi.c | 27 ++++++++++++++++++++++++--- 2 files changed, 25 insertions(+), 4 deletions(-) (limited to 'drivers/tty/serial') diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 732c893c8d16..1f2594b8ab9d 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -87,7 +87,7 @@ config SERIAL_EARLYCON_SEMIHOST config SERIAL_EARLYCON_RISCV_SBI bool "Early console using RISC-V SBI" - depends on RISCV_SBI_V01 + depends on RISCV_SBI select SERIAL_CORE select SERIAL_CORE_CONSOLE select SERIAL_EARLYCON diff --git a/drivers/tty/serial/earlycon-riscv-sbi.c b/drivers/tty/serial/earlycon-riscv-sbi.c index 27afb0b74ea7..0162155f0c83 100644 --- a/drivers/tty/serial/earlycon-riscv-sbi.c +++ b/drivers/tty/serial/earlycon-riscv-sbi.c @@ -15,17 +15,38 @@ static void sbi_putc(struct uart_port *port, unsigned char c) sbi_console_putchar(c); } -static void sbi_console_write(struct console *con, - const char *s, unsigned n) +static void sbi_0_1_console_write(struct console *con, + const char *s, unsigned int n) { struct earlycon_device *dev = con->data; uart_console_write(&dev->port, s, n, sbi_putc); } +static void sbi_dbcn_console_write(struct console *con, + const char *s, unsigned int n) +{ + int ret; + + while (n) { + ret = sbi_debug_console_write(s, n); + if (ret < 0) + break; + + s += ret; + n -= ret; + } +} + static int __init early_sbi_setup(struct earlycon_device *device, const char *opt) { - device->con->write = sbi_console_write; + if (sbi_debug_console_available) + device->con->write = sbi_dbcn_console_write; + else if (IS_ENABLED(CONFIG_RISCV_SBI_V01)) + device->con->write = sbi_0_1_console_write; + else + return -ENODEV; + return 0; } EARLYCON_DECLARE(sbi, early_sbi_setup); -- cgit v1.2.3