diff options
Diffstat (limited to 'target/linux/mpc85xx/image/spi-loader/drivers/serial/ns16550.c')
-rw-r--r-- | target/linux/mpc85xx/image/spi-loader/drivers/serial/ns16550.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/target/linux/mpc85xx/image/spi-loader/drivers/serial/ns16550.c b/target/linux/mpc85xx/image/spi-loader/drivers/serial/ns16550.c new file mode 100644 index 0000000000..d4549176b1 --- /dev/null +++ b/target/linux/mpc85xx/image/spi-loader/drivers/serial/ns16550.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 16550 serial console support. + * + * Original copied from <file:arch/ppc/boot/common/ns16550.c> + * (which had no copyright) + * Modifications: 2006 (c) MontaVista Software, Inc. + * + * Modified by: Mark A. Greer <mgreer@mvista.com> + * + * Adapted by: + * + * Copyright (c) 2022 Matthias Schiffer <mschiffer@universe-factory.net> + */ + +#include <io.h> +#include <serial.h> + +#define UART_DLL 0 /* Out: Divisor Latch Low */ +#define UART_DLM 1 /* Out: Divisor Latch High */ +#define UART_FCR 2 /* Out: FIFO Control Register */ +#define UART_LCR 3 /* Out: Line Control Register */ +#define UART_MCR 4 /* Out: Modem Control Register */ +#define UART_LSR 5 /* In: Line Status Register */ +#define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */ +#define UART_LSR_DR 0x01 /* Receiver data ready */ +#define UART_MSR 6 /* In: Modem Status Register */ +#define UART_SCR 7 /* I/O: Scratch Register */ + +static uint8_t *const reg_base = (uint8_t *)CONFIG_SERIAL_NS16550_REG_BASE; +static const int reg_shift = CONFIG_SERIAL_NS16550_REG_SHIFT; + +void serial_console_putchar(char c) +{ + while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_THRE) == 0); + out_8(reg_base, c); +} + +int serial_console_getc(void) +{ + while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) == 0); + return in_8(reg_base); +} + +int serial_console_tstc(void) +{ + return ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) != 0); +} + +void serial_console_init(void) +{ + out_8(reg_base + (UART_FCR << reg_shift), 0x06); +} |