blob: 0b5ce06853e4101a0e1a28b7ba13ac9f4847dd19 [file] [log] [blame]
/***********************************************************************
*
* (C) Copyright 2004-2009
* DENX Software Engineering
* Wolfgang Denk, wd@denx.de
*
* Simple 16550A serial driver
*
* Originally from linux source (drivers/char/ps2ser.c)
*
* Used by the PS/2 multiplexer driver (ps2mult.c)
*
***********************************************************************/
#include <common.h>
#include <asm/io.h>
#include <asm/atomic.h>
#include <ps2mult.h>
/* This is needed for ns16550.h */
#ifndef CONFIG_SYS_NS16550_REG_SIZE
#define CONFIG_SYS_NS16550_REG_SIZE 1
#endif
#include <ns16550.h>
DECLARE_GLOBAL_DATA_PTR;
/* #define DEBUG */
#define PS2SER_BAUD 57600
#if CONFIG_PS2SERIAL == 1
#define COM_BASE (CONFIG_SYS_CCSRBAR+0x4500)
#elif CONFIG_PS2SERIAL == 2
#define COM_BASE (CONFIG_SYS_CCSRBAR+0x4600)
#else
#error CONFIG_PS2SERIAL must be in 1 ... 2
#endif
static int ps2ser_getc_hw(void);
static void ps2ser_interrupt(void *dev_id);
extern struct serial_state rs_table[]; /* in serial.c */
static u_char ps2buf[PS2BUF_SIZE];
static atomic_t ps2buf_cnt;
static int ps2buf_in_idx;
static int ps2buf_out_idx;
int ps2ser_init(void)
{
NS16550_t com_port = (NS16550_t)COM_BASE;
com_port->ier = 0x00;
com_port->lcr = UART_LCR_BKSE | UART_LCR_8N1;
com_port->dll = (CONFIG_SYS_NS16550_CLK / 16 / PS2SER_BAUD) & 0xff;
com_port->dlm = ((CONFIG_SYS_NS16550_CLK / 16 / PS2SER_BAUD) >> 8) & 0xff;
com_port->lcr = UART_LCR_8N1;
com_port->mcr = (UART_MCR_DTR | UART_MCR_RTS);
com_port->fcr = (UART_FCR_FIFO_EN | UART_FCR_RXSR | UART_FCR_TXSR);
return (0);
}
void ps2ser_putc(int chr)
{
NS16550_t com_port = (NS16550_t)COM_BASE;
debug(">>>> 0x%02x\n", chr);
while ((com_port->lsr & UART_LSR_THRE) == 0);
com_port->thr = chr;
}
static int ps2ser_getc_hw(void)
{
NS16550_t com_port = (NS16550_t)COM_BASE;
int res = -1;
if (com_port->lsr & UART_LSR_DR) {
res = com_port->rbr;
}
return res;
}
int ps2ser_getc(void)
{
volatile int chr;
int flags;
debug("<< ");
flags = disable_interrupts();
do {
if (atomic_read(&ps2buf_cnt) != 0) {
chr = ps2buf[ps2buf_out_idx++];
ps2buf_out_idx &= (PS2BUF_SIZE - 1);
atomic_dec(&ps2buf_cnt);
} else {
chr = ps2ser_getc_hw();
}
}
while (chr < 0);
if (flags)
enable_interrupts();
debug("0x%02x\n", chr);
return chr;
}
int ps2ser_check(void)
{
int flags;
flags = disable_interrupts();
ps2ser_interrupt(NULL);
if (flags) enable_interrupts();
return atomic_read(&ps2buf_cnt);
}
static void ps2ser_interrupt(void *dev_id)
{
NS16550_t com_port = (NS16550_t)COM_BASE;
int chr;
int status;
do {
chr = ps2ser_getc_hw();
status = com_port->lsr;
if (chr < 0) continue;
if (atomic_read(&ps2buf_cnt) < PS2BUF_SIZE) {
ps2buf[ps2buf_in_idx++] = chr;
ps2buf_in_idx &= (PS2BUF_SIZE - 1);
atomic_inc(&ps2buf_cnt);
} else {
printf ("ps2ser.c: buffer overflow\n");
}
} while (status & UART_LSR_DR);
if (atomic_read(&ps2buf_cnt)) {
ps2mult_callback(atomic_read(&ps2buf_cnt));
}
}