diff options
Diffstat (limited to 'sys/dev/uart/uart_dev_ns8250.c')
| -rw-r--r-- | sys/dev/uart/uart_dev_ns8250.c | 51 |
1 files changed, 48 insertions, 3 deletions
diff --git a/sys/dev/uart/uart_dev_ns8250.c b/sys/dev/uart/uart_dev_ns8250.c index c38d50e54ad8..c13eabe9055e 100644 --- a/sys/dev/uart/uart_dev_ns8250.c +++ b/sys/dev/uart/uart_dev_ns8250.c @@ -89,9 +89,7 @@ SYSCTL_INT(_hw, OID_AUTO, uart_noise_threshold, CTLFLAG_RWTUN, * options EARLY_PRINTF=ns8250 */ #if CHECK_EARLY_PRINTF(ns8250) -#if !(defined(__amd64__) || defined(__i386__)) -#error ns8250 early putc is x86 specific as it uses inb/outb -#endif +#if (defined(__amd64__) || defined(__i386__)) static void uart_ns8250_early_putc(int c) { @@ -103,7 +101,45 @@ uart_ns8250_early_putc(int c) continue; outb(tx, c); } +#elif (defined(__arm__) || defined(__aarch64__)) +#ifndef UART_NS8250_EARLY_REG_IO_WIDTH +#error Option 'UART_NS8250_EARLY_REG_IO_WIDTH' is missing. +#endif +#ifndef UART_NS8250_EARLY_REG_SHIFT +#error Option 'UART_NS8250_EARLY_REG_SHIFT' is missing. +#endif + +#if UART_NS8250_EARLY_REG_IO_WIDTH == 1 +#define T uint8_t +#elif UART_NS8250_EARLY_REG_IO_WIDTH == 2 +#define T uint16_t +#elif UART_NS8250_EARLY_REG_IO_WIDTH == 4 +#define T uint32_t + +#else +#error Invalid/unsupported UART_NS8250_EARLY_REG_IO_WIDTH value +#endif + +#include <machine/machdep.h> + +static void +uart_ns8250_early_putc(int c) +{ + volatile T *stat; + volatile T *tx; + + stat = (T *)(socdev_va + (REG_LSR << UART_NS8250_EARLY_REG_SHIFT)); + tx = (T *)(socdev_va + (REG_DATA << UART_NS8250_EARLY_REG_SHIFT)); + + while ((*stat & LSR_THRE) == 0) + continue; + *tx = c & 0xff; +} +#else +#error ns8250 early putc is not implemented for current architecture +#endif early_putc_t *early_putc = uart_ns8250_early_putc; +#undef DTYPE #endif /* EARLY_PRINTF */ /* @@ -963,6 +999,15 @@ ns8250_bus_probe(struct uart_softc *sc) uart_setreg(bas, REG_IER, ier); uart_setreg(bas, REG_MCR, mcr); uart_setreg(bas, REG_FCR, 0); + /* + * The Alder Lake AMT SOL Redirection device will never + * set LSR_OE (when in loopback mode at least) and + * instead block further input by not setting LSR_TEMT. + * Recovering the device afterwards into a working + * state requires re-writing the LCR register. This + * should be harmless on all other devices. + */ + uart_setreg(bas, REG_LCR, uart_getreg(bas, REG_LCR)); uart_barrier(bas); count = 0; goto describe; |