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/*
* COM1 NS16550 support
* originally from linux source (arch/powerpc/boot/ns16550.c)
* modified to use CONFIG_SYS_ISA_MEM and new defines
*/
#include <common.h>
#include <config.h>
#include <common.h>
#include <ns16550.h>
#include <watchdog.h>
#include <linux/types.h>
#include <asm/io.h>
#include "uart-spi-fix.h"
DECLARE_GLOBAL_DATA_PTR;
#define UART_LCRVAL UART_LCR_8N1 /* 8 data, 1 stop, no parity */
#define UART_MCRVAL (UART_MCR_DTR | \
UART_MCR_RTS) /* RTS/DTR */
#define UART_FCRVAL (UART_FCR_FIFO_EN | \
UART_FCR_RXSR | \
UART_FCR_TXSR) /* Clear & enable FIFOs */
#if defined(CONFIG_SYS_NS16550_RUNTIME_MAPPED)
#define serial_out(x,y) if (NS16550_io_mapped) \
outb(x,(ulong)y); \
else \
writeb(x,y)
#define serial_in(y) (NS16550_io_mapped ? inb((ulong)y) : readb(y))
#elif defined(CONFIG_SYS_NS16550_PORT_MAPPED)
#define serial_out(x,y) outb(x,(ulong)y)
#define serial_in(y) inb((ulong)y)
#else
#define serial_out(x,y) writeb(x,y)
#define serial_in(y) readb(y)
#endif
#ifndef CONFIG_SYS_NS16550_IER
#define CONFIG_SYS_NS16550_IER 0x00
#endif /* CONFIG_SYS_NS16550_IER */
#if defined(CONFIG_SYS_NS16550_RUNTIME_MAPPED)
/* This state variable has to be set by a wrapper driver
* that knows whether we're operating on an IO mapped or
* memory mapped 16550 compatible chip.
* See serial_fdt.c for an example.
*/
static int NS16550_io_mapped;
void NS16550_is_io_mapped(int io_mapped)
{
NS16550_io_mapped = io_mapped;
}
#endif
void NS16550_init (NS16550_t com_port, int baud_divisor)
{
serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
#if defined(CONFIG_OMAP) && !defined(CONFIG_OMAP3_ZOOM2)
serial_out(0x7, &com_port->mdr1); /* mode select reset TL16C750*/
#endif
serial_out(UART_LCR_BKSE | UART_LCRVAL, (ulong)&com_port->lcr);
serial_out(0, &com_port->dll);
serial_out(0, &com_port->dlm);
serial_out(UART_LCRVAL, &com_port->lcr);
serial_out(UART_MCRVAL, &com_port->mcr);
serial_out(UART_FCRVAL, &com_port->fcr);
serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr);
serial_out(baud_divisor & 0xff, &com_port->dll);
serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm);
serial_out(UART_LCRVAL, &com_port->lcr);
/*
* Put a 'D' in the scratchpad to let the kernel know which UART
* for earlyprintk [D]ebugging.
*/
serial_out('D', &com_port->spr);
#if defined(CONFIG_OMAP) && !defined(CONFIG_OMAP3_ZOOM2)
#if defined(CONFIG_APTIX)
serial_out(3, &com_port->mdr1); /* /13 mode so Aptix 6MHz can hit 115200 */
#else
serial_out(0, &com_port->mdr1); /* /16 is proper to hit 115200 with 48MHz */
#endif
#endif /* CONFIG_OMAP */
}
#ifndef CONFIG_NS16550_MIN_FUNCTIONS
void NS16550_reinit (NS16550_t com_port, int baud_divisor)
{
serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr);
serial_out(0, &com_port->dll);
serial_out(0, &com_port->dlm);
serial_out(UART_LCRVAL, &com_port->lcr);
serial_out(UART_MCRVAL, &com_port->mcr);
serial_out(UART_FCRVAL, &com_port->fcr);
serial_out(UART_LCR_BKSE, &com_port->lcr);
serial_out(baud_divisor & 0xff, &com_port->dll);
serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm);
serial_out(UART_LCRVAL, &com_port->lcr);
}
#endif /* CONFIG_NS16550_MIN_FUNCTIONS */
void NS16550_putc(NS16550_t regs, char c)
{
uart_enable(regs);
while ((serial_in(®s->lsr) & UART_LSR_THRE) == 0);
serial_out(c, ®s->thr);
/*
* Call watchdog_reset() upon newline. This is done here in putc
* since the environment code uses a single puts() to print the complete
* environment upon "printenv". So we can't put this watchdog call
* in puts().
*/
if (c == '\n')
WATCHDOG_RESET();
}
#ifndef CONFIG_NS16550_MIN_FUNCTIONS
static char NS16550_raw_getc(NS16550_t regs)
{
uart_enable(regs);
while ((serial_in(®s->lsr) & UART_LSR_DR) == 0) {
#ifdef CONFIG_USB_TTY
extern void usbtty_poll(void);
usbtty_poll();
#endif
WATCHDOG_RESET();
}
return serial_in(®s->rbr);
}
static int NS16550_raw_tstc(NS16550_t regs)
{
uart_enable(regs);
return ((serial_in(®s->lsr) & UART_LSR_DR) != 0);
}
#ifdef CONFIG_NS16550_BUFFER_READS
#define BUF_SIZE 256
#define NUM_PORTS 4
struct ns16550_priv {
char buf[BUF_SIZE];
unsigned int head, tail;
};
static struct ns16550_priv rxstate[NUM_PORTS];
static void enqueue(unsigned int port, char ch)
{
/* If queue is full, drop the character. */
if ((rxstate[port].head - rxstate[port].tail - 1) % BUF_SIZE == 0)
return;
rxstate[port].buf[rxstate[port].tail] = ch;
rxstate[port].tail = (rxstate[port].tail + 1) % BUF_SIZE;
}
static int dequeue(unsigned int port, char *ch)
{
/* Empty queue? */
if (rxstate[port].head == rxstate[port].tail)
return 0;
*ch = rxstate[port].buf[rxstate[port].head];
rxstate[port].head = (rxstate[port].head + 1) % BUF_SIZE;
return 1;
}
static void fill_rx_buf(NS16550_t regs, unsigned int port)
{
uart_enable(regs);
while ((serial_in(®s->lsr) & UART_LSR_DR) != 0)
enqueue(port, serial_in(®s->rbr));
}
char NS16550_getc(NS16550_t regs, unsigned int port)
{
char ch;
if (port >= NUM_PORTS || !(gd->flags & GD_FLG_RELOC))
return NS16550_raw_getc(regs);
do {
#ifdef CONFIG_USB_TTY
extern void usbtty_poll(void);
usbtty_poll();
#endif
fill_rx_buf(regs, port);
WATCHDOG_RESET();
} while (!dequeue(port, &ch));
return ch;
}
int NS16550_tstc(NS16550_t regs, unsigned int port)
{
if (port >= NUM_PORTS || !(gd->flags & GD_FLG_RELOC))
return NS16550_raw_tstc(regs);
fill_rx_buf(regs, port);
return rxstate[port].head != rxstate[port].tail;
}
#else /* CONFIG_NS16550_BUFFER_READS */
char NS16550_getc(NS16550_t regs, unsigned int port)
{
return NS16550_raw_getc(regs);
}
int NS16550_tstc(NS16550_t regs, unsigned int port)
{
return NS16550_raw_tstc(regs);
}
#endif /* CONFIG_NS16550_BUFFER_READS */
/* Clear the UART's RX FIFO */
void NS16550_clear(NS16550_t regs, unsigned port)
{
/* Reset RX fifo */
serial_out(UART_FCR_FIFO_EN | UART_FCR_RXSR, ®s->fcr);
/* Remove any pending characters */
while (NS16550_raw_tstc(regs))
NS16550_raw_getc(regs);
}
/* Wait for the UART's output buffer and holding register to drain */
void NS16550_drain(NS16550_t regs, unsigned port)
{
u32 mask = UART_LSR_TEMT | UART_LSR_THRE;
/* Wait for the UART to finish sending */
while ((serial_in(®s->lsr) & mask) != mask)
udelay(100);
#ifdef CONFIG_NS16550_BUFFER_READS
/* Quickly grab any incoming data while we can */
fill_rx_buf(regs, port);
#endif
}
#endif /* CONFIG_NS16550_MIN_FUNCTIONS */
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