int serial_init(void) {
u32 rdata;
u32 baudRateDivisor, clock_step;
u32 fcEnable = 0;
u32 ahb_freq, ddr_freq, cpu_freq;
ar7240_sys_frequency(&cpu_freq, &ddr_freq, &ahb_freq);
/* GPIO Configuration */
ar7240_reg_wr(AR7240_GPIO_OE, 0xcff);
rdata = ar7240_reg_rd(AR7240_GPIO_OUT);
rdata |= 0x400; // GPIO 10 (UART_SOUT) must output 1
ar7240_reg_wr(AR7240_GPIO_OUT, rdata);
rdata = ar7240_reg_rd(AR7240_GPIO_FUNC);
/* GPIO_FUN, bit1/UART_EN, bit2/UART_RTS_CTS_EN, bit15(disable_s26_uart) */
rdata |= (0x3 << 1) | (0x1 << 15);
ar7240_reg_wr(AR7240_GPIO_FUNC, rdata);
/* Get reference clock rate, then set baud rate to 115200 */
// TODO: check the following code
rdata = ar7240_reg_rd(HORNET_BOOTSTRAP_STATUS);
rdata &= HORNET_BOOTSTRAP_SEL_25M_40M_MASK;
if (rdata) {
baudRateDivisor = (40000000 / (16 * 115200)) - 1; // 40 MHz clock is taken as UART clock
} else {
baudRateDivisor = (25000000 / (16 * 115200)) - 1; // 25 MHz clock is taken as UART clock
}
clock_step = 8192;
rdata = UARTCLOCK_UARTCLOCKSCALE_SET(baudRateDivisor) | UARTCLOCK_UARTCLOCKSTEP_SET(clock_step);
uart_reg_write(UARTCLOCK_ADDRESS, rdata);
/* Config Uart Controller */
/* No interrupt */
rdata = UARTCS_UARTDMAEN_SET(0) | UARTCS_UARTHOSTINTEN_SET(0) | UARTCS_UARTHOSTINT_SET(0) | UARTCS_UARTSERIATXREADY_SET(0) | UARTCS_UARTTXREADYORIDE_SET(~fcEnable) | UARTCS_UARTRXREADYORIDE_SET(~fcEnable) | UARTCS_UARTHOSTINTEN_SET(0);
/* is_dte == 1 */
rdata = rdata | UARTCS_UARTINTERFACEMODE_SET(2);
if (fcEnable) {
rdata = rdata | UARTCS_UARTFLOWCONTROLMODE_SET(2);
}
/* invert_fc ==0 (Inverted Flow Control) */
//rdata = rdata | UARTCS_UARTFLOWCONTROLMODE_SET(3);
/* parityEnable == 0 */
//rdata = rdata | UARTCS_UARTPARITYMODE_SET(2); -->Parity Odd
//rdata = rdata | UARTCS_UARTPARITYMODE_SET(3); -->Parity Even
uart_reg_write(UARTCS_ADDRESS, rdata);
return 0;
}
void UartInit(void)
{
unsigned int rdata;
unsigned int baudRateDivisor, clock_step;
unsigned int fcEnable = 0;
ath_sys_frequency();
MY_WRITE(0xb8040000, 0xcff);
MY_WRITE(0xb8040008, 0x3b);
/* Enable UART , SPI and Disable S26 UART */
MY_WRITE(0xb8040028, (ath_reg_rd(0xb8040028) | 0x48002));
MY_WRITE(0xb8040008, 0x2f);
#ifdef CONFIG_HORNET_EMULATION
baudRateDivisor = (ath_ahb_freq / (16 * ATH_CONSOLE_BAUD)) - 1; // 24 MHz clock is taken as UART clock
#else
rdata = ath_reg_rd(HORNET_BOOTSTRAP_STATUS);
rdata &= HORNET_BOOTSTRAP_SEL_25M_40M_MASK;
if (rdata)
baudRateDivisor = (40000000 / (16 * ATH_CONSOLE_BAUD)) - 1; // 40 MHz clock is taken as UART clock
else
baudRateDivisor = (25000000 / (16 * ATH_CONSOLE_BAUD)) - 1; // 25 MHz clock is taken as UART clock
#endif
clock_step = 8192;
rdata =
UARTCLOCK_UARTCLOCKSCALE_SET(baudRateDivisor) |
UARTCLOCK_UARTCLOCKSTEP_SET(clock_step);
uart_reg_write(UARTCLOCK_ADDRESS, rdata);
/* Config Uart Controller */
#if 1 /* No interrupt */
rdata =
UARTCS_UARTDMAEN_SET(0) | UARTCS_UARTHOSTINTEN_SET(0) |
UARTCS_UARTHOSTINT_SET(0)
| UARTCS_UARTSERIATXREADY_SET(0) |
UARTCS_UARTTXREADYORIDE_SET(~fcEnable)
| UARTCS_UARTRXREADYORIDE_SET(~fcEnable) |
UARTCS_UARTHOSTINTEN_SET(0);
#else
rdata =
UARTCS_UARTDMAEN_SET(0) | UARTCS_UARTHOSTINTEN_SET(0) |
UARTCS_UARTHOSTINT_SET(0)
| UARTCS_UARTSERIATXREADY_SET(0) |
UARTCS_UARTTXREADYORIDE_SET(~fcEnable)
| UARTCS_UARTRXREADYORIDE_SET(~fcEnable) |
UARTCS_UARTHOSTINTEN_SET(1);
#endif
/* is_dte == 1 */
rdata = rdata | UARTCS_UARTINTERFACEMODE_SET(2);
if (fcEnable) {
rdata = rdata | UARTCS_UARTFLOWCONTROLMODE_SET(2);
}
/* invert_fc ==0 (Inverted Flow Control) */
//rdata = rdata | UARTCS_UARTFLOWCONTROLMODE_SET(3);
/* parityEnable == 0 */
//rdata = rdata | UARTCS_UARTPARITYMODE_SET(2); -->Parity Odd
//rdata = rdata | UARTCS_UARTPARITYMODE_SET(3); -->Parity Even
uart_reg_write(UARTCS_ADDRESS, rdata);
serial_inited = 1;
}
