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#include <apos/types.h>
#include <apos/debug.h>
#ifdef DEBUG
/* if there arises a need for more supported serial drivers, I should probably
* try to implement some kind of basic driver subsystem, but this is good enough
* for now. */
struct __packed ns16550a {
union {
struct {
uint8_t data;
uint8_t irq;
};
struct {
uint8_t lsbr;
uint8_t msbr;
};
};
uint8_t irq_id;
uint8_t lcr;
uint8_t mcr;
uint8_t lsr;
uint8_t msr;
uint8_t scr;
};
#define LSR_DR (1 << 0)
#define LSR_OE (1 << 1)
#define LSR_PE (1 << 2)
#define LSR_FE (1 << 3)
#define LSR_BI (1 << 4)
#define LSR_THRE (1 << 5)
#define LSR_TEMT (1 << 6)
#define LSR_ERR (1 << 7)
static struct ns16550a *port = 0;
int __serial_tx_empty()
{
return port->lsr & LSR_THRE;
}
void __serial_putchar(char c)
{
if (!port)
return;
while(__serial_tx_empty() == 0);
port->data = c;
}
void dbg_init(void *pt, enum serial_dev_t dev)
{
switch (dev) {
case NS16550A:
port = pt;
break;
}
/* in the future possibly configure the serial connection, though the
* defaults (set by U-boot) seem to work alright */
}
void dbg(const char *fmt, ...)
{
/* do a proper implementation later, for now just dump stuff */
while(*fmt){
__serial_putchar(*fmt++);
}
}
#endif /* DEBUG */
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