56 lines
2.0 KiB
C
56 lines
2.0 KiB
C
#ifndef COSMOPOLITAN_LIBC_NEXGEN32E_UART_H_
|
|
#define COSMOPOLITAN_LIBC_NEXGEN32E_UART_H_
|
|
|
|
/**
|
|
* @fileoverview PC Serial Line Helpers (8250 UART 16550+).
|
|
*
|
|
* <p>These functions provide the baseline of PC telecommunications
|
|
* support that doesn't require switching context or cpu mode.
|
|
*
|
|
* <p>Example use cases:
|
|
* <ul>
|
|
* <li>Qemu stdio
|
|
* <li>Bare metal stdio
|
|
* <li>FIPS-170-2 SSH alternative
|
|
* <li>NIC for key-signing servers
|
|
* </ul>
|
|
*
|
|
* @see www.lammertbies.nl/comm/info/serial-uart.html
|
|
*/
|
|
|
|
#define COM1 0x0 /* offset in pc bios data area with port number (0x400) */
|
|
#define COM2 0x2
|
|
#define COM3 0x4
|
|
#define COM4 0x6
|
|
#define IRQ3 0x0b /* com2 interrupt number (irq3) */
|
|
#define IRQ4 0x0c /* com1 interrupt number (irq4) */
|
|
#define UART_DLAB (1 << 7) /* serial line conf mode bit */
|
|
#define UART_DLL 0 /* divisor latch register */
|
|
#define UART_DLM 1 /* divisor latch register */
|
|
#define UART_IIR 2 /* interrupt identification register */
|
|
#define UART_LCR 3 /* line control register */
|
|
#define UART_MCR 4 /* modem control register */
|
|
#define UART_LSR 5 /* line status register */
|
|
#define UART_TTYDA (1 << 0) /* data available (rx ready) */
|
|
#define UART_TTYOE (1 << 1) /* overrun error */
|
|
#define UART_TTYPE (1 << 2) /* parity error */
|
|
#define UART_TTYFE (1 << 3) /* framing error */
|
|
#define UART_TTYBSR (1 << 4) /* break signal received */
|
|
#define UART_TTYTXR (1 << 5) /* serial thr empty (tx ready) */
|
|
#define UART_TTYIDL (1 << 6) /* serial thr empty and line idle */
|
|
#define UART_TTYEDF (1 << 7) /* erroneous data in fifo */
|
|
|
|
#if !(__ASSEMBLER__ + __LINKER__ + 0)
|
|
COSMOPOLITAN_C_START_
|
|
|
|
void sinit(unsigned short *ports, unsigned count, const char *config);
|
|
void sputc(unsigned char ch, int port);
|
|
int sgetc(int port);
|
|
void sputs(const char *s, int port);
|
|
void sflush(unsigned short *ports, unsigned count);
|
|
unsigned char slsr(int port);
|
|
|
|
COSMOPOLITAN_C_END_
|
|
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
|
|
#endif /* COSMOPOLITAN_LIBC_NEXGEN32E_UART_H_ */
|