| 0,0 → 1,127 |
|---|
| #include <unistd.h> |
| #include <ddi.h> |
| #include <libarch/ddi.h> |
| #include <stdio.h> |
| |
| #include "isa.h" |
| #include "serial.h" |
| |
| #define NAME "serial" |
| |
| #define REG_COUNT 7 |
| #define COM1 0x3F8 |
| #define COM2 0x2F8 |
| |
| static ioport8_t *com1 = 0, *com2 = 0; |
| |
| static void serial_init_port(ioport8_t *port); |
| static void serial_write_8(ioport8_t *port, uint8_t c); |
| static bool is_transmit_empty(ioport8_t *port); |
| static uint8_t serial_read_8(ioport8_t *port); |
| static bool serial_received(ioport8_t *port); |
| static void serial_probe(bridge_to_isa_t *parent); |
| static void * serial_probe_port(void *phys_addr); |
| |
| static isa_drv_ops_t serial_isa_ops = { |
| .probe = serial_probe |
| }; |
| |
| static isa_drv_t serial_isa_drv = { |
| .name = NAME, |
| .ops = &serial_isa_ops |
| }; |
| |
| int serial_init() |
| { |
| // TODO: register this driver by generic isa bus driver |
| |
| isa_register_driver(&serial_isa_drv); |
| return 1; |
| } |
| |
| static bool serial_received(ioport8_t *port) |
| { |
| return (pio_read_8(port + 5) & 1) != 0; |
| } |
| |
| static uint8_t serial_read_8(ioport8_t *port) |
| { |
| while (!serial_received(port)) |
| ; |
| |
| uint8_t c = pio_read_8(port); |
| return c; |
| } |
| |
| static bool is_transmit_empty(ioport8_t *port) |
| { |
| return (pio_read_8(port + 5) & 0x20) != 0; |
| } |
| |
| static void serial_write_8(ioport8_t *port, uint8_t c) |
| { |
| while (!is_transmit_empty(port)) |
| ; |
| |
| pio_write_8(port, c); |
| } |
| |
| static void serial_init_port(ioport8_t *port) |
| { |
| pio_write_8(port + 1, 0x00); // Disable all interrupts |
| pio_write_8(port + 3, 0x80); // Enable DLAB (set baud rate divisor) |
| pio_write_8(port + 0, 0x60); // Set divisor to 96 (lo byte) 1200 baud |
| pio_write_8(port + 1, 0x00); // (hi byte) |
| pio_write_8(port + 3, 0x07); // 8 bits, no parity, two stop bits |
| pio_write_8(port + 2, 0xC7); // Enable FIFO, clear them, with 14-byte threshold |
| pio_write_8(port + 4, 0x0B); // IRQs enabled, RTS/DSR set |
| } |
| |
| static void serial_probe(bridge_to_isa_t *parent) |
| { |
| printf(NAME " driver: probe()\n"); |
| |
| printf(NAME " driver: probing com1 \n"); |
| if (com1 = (ioport8_t *)serial_probe_port(parent->ops->absolutize(COM1))) { |
| printf(NAME " driver: initializing com1 \n"); |
| serial_init_port(com1); |
| } else { |
| printf(NAME " driver: com1 is not present \n"); |
| } |
| |
| printf(NAME " driver: probing com2 \n"); |
| if (com2 = (ioport8_t *)serial_probe_port(parent->ops->absolutize(COM2))) { |
| printf(NAME " driver: initializing com2 \n"); |
| serial_init_port(com2); |
| } |
| else { |
| printf(NAME " driver: com2 is not present \n"); |
| } |
| } |
| |
| // returns virtual address of the serial port, if the serial port is present at this physical address, NULL otherwise |
| static void * serial_probe_port(void *phys_addr) |
| { |
| ioport8_t *port_addr = NULL; |
| |
| if (pio_enable(phys_addr, REG_COUNT, (void **)(&port_addr))) { // Gain control over port's registers. |
| printf(NAME ": Error - cannot gain the port %lx.\n", phys_addr); |
| return NULL; |
| } |
| |
| uint8_t olddata; |
| |
| olddata = pio_read_8(port_addr + 4); |
| pio_write_8(port_addr + 4, 0x10); |
| if ((pio_read_8(port_addr + 6) & 0xf0)) { |
| return NULL; |
| } |
| |
| pio_write_8(port_addr + 4, 0x1f); |
| if ((pio_read_8(port_addr + 6) & 0xf0) != 0xf0) { |
| return 0; |
| } |
| pio_write_8(port_addr + 4, olddata); |
| |
| return port_addr; |
| } |