void PutUARTByte (const char c)
{
while (!(UART_READ32 (UART_LSR(g_uart)) & UART_LSR_THRE))
{
}
if (c == '\n')
UART_WRITE32 ((unsigned int) '\r', UART_THR(g_uart));
UART_WRITE32 ((unsigned int) c, UART_THR(g_uart));
}
void serial_setbrg()
{
unsigned int byte,speed;
unsigned int highspeed;
unsigned int quot, divisor, remainder;
//unsigned int ratefix;
unsigned int uartclk;
//unsigned int highclk = (UART_SRC_CLK/(speed*4)) > 10 ? (1) : 0;
unsigned short data, high_speed_div, sample_count, sample_point;
unsigned int tmp_div;
speed = g_brg;
//uartclk = UART_SRC_CLK;
uartclk = (unsigned int)(mt6575_get_bus_freq()*1000/4);
if (speed <= 115200 ) {
highspeed = 0;
quot = 16;
} else {
highspeed = 3;
quot = 1;
}
if (highspeed < 3) { /*0~2*/
/* Set divisor DLL and DLH */
divisor = uartclk / (quot * speed);
remainder = uartclk % (quot * speed);
if (remainder >= (quot / 2) * speed)
divisor += 1;
UART_WRITE16(highspeed, UART_HIGHSPEED(g_uart));
byte = UART_READ32(UART_LCR(g_uart)); /* DLAB start */
UART_WRITE32((byte | UART_LCR_DLAB), UART_LCR(g_uart));
UART_WRITE32((divisor & 0x00ff), UART_DLL(g_uart));
UART_WRITE32(((divisor >> 8)&0x00ff), UART_DLH(g_uart));
UART_WRITE32(byte, UART_LCR(g_uart)); /* DLAB end */
} else {
void serial_setbrg (U32 uartclk, U32 baudrate)
{
#if (CFG_FPGA_PLATFORM)
#define MAX_SAMPLE_COUNT 256
U16 tmp;
U32 divisor;
U32 sample_data;
U32 sample_count;
U32 sample_point;
// Setup N81,(UART_WLS_8 | UART_NONE_PARITY | UART_1_STOP) = 0x03
UART_WRITE32(0x0003, UART_LCR(g_uart));
/*
* NoteXXX: Below is the sample code to set UART baud rate.
* I assume that when system is reset, the UART clock rate is 26MHz
* and baud rate is 115200.
* use UART1_HIGHSPEED = 0x3 can get more sample count to get better UART sample rate
* based on baud_rate = uart clock frequency / (sampe_count * divisor)
* divisor = (DLH+DLL)
*/
// In order to get better UART sample rate, set UART1_HIGHSPEED = 0x3.
// And we can calculate sample count for reducing effect of UART sample rate variation
UART_WRITE32(0x0003, UART_HIGHSPEED(g_uart));
// calculate sample_data = sample_count*divisor
// round off the result for approximating to the real baudrate
sample_data = (uartclk+(baudrate/2))/baudrate;
// calculate divisor
divisor = (sample_data+(MAX_SAMPLE_COUNT-1))/MAX_SAMPLE_COUNT;
// calculate sample count
sample_count = sample_data/divisor;
// calculate sample point (count from 0)
sample_point = (sample_count-1)/2;
// set sample count (count from 0)
UART_WRITE32((sample_count-1), UART_SAMPLE_COUNT(g_uart));
// set sample point
UART_WRITE32(sample_point, UART_SAMPLE_POINT(g_uart));
tmp = UART_READ32(UART_LCR(g_uart)); /* DLAB start */
UART_WRITE32((tmp | UART_LCR_DLAB), UART_LCR(g_uart));
UART_WRITE32((divisor&0xFF), UART_DLL(g_uart));
UART_WRITE32(((divisor>>8)&0xFF), UART_DLH(g_uart));
UART_WRITE32(tmp, UART_LCR(g_uart));
#else
unsigned int byte;
unsigned int highspeed;
unsigned int quot, divisor, remainder;
unsigned int ratefix;
if (baudrate <= 115200 ) {
highspeed = 0;
quot = 16;
} else {
highspeed = 2;
quot = 4;
}
/* Set divisor DLL and DLH */
divisor = uartclk / (quot * baudrate);
remainder = uartclk % (quot * baudrate);
if (remainder >= (quot / 2) * baudrate)
divisor += 1;
UART_WRITE16(highspeed, UART_HIGHSPEED(g_uart));
byte = UART_READ32(UART_LCR(g_uart)); /* DLAB start */
UART_WRITE32((byte | UART_LCR_DLAB), UART_LCR(g_uart));
UART_WRITE32((divisor & 0x00ff), UART_DLL(g_uart));
UART_WRITE32(((divisor >> 8)&0x00ff), UART_DLH(g_uart));
//UART_WRITE32(byte, UART_LCR(g_uart)); /* DLAB end */
// Setup N81,(UART_WLS_8 | UART_NONE_PARITY | UART_1_STOP) = 0x03
UART_WRITE32(0x0003, UART_LCR(g_uart));
#endif
}
