/*
* Read a single byte from the serial port. Returns 1 on success, 0
* otherwise. When the function is succesfull, the character read is
* written into its argument c.
*/
int serial_getc_dev(const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
/* wait for character to arrive */
while (!(readl(&uart->utrstat) & 0x1)) {
if (serial_err_check(dev_index, 0))
return 0;
}
return (int)(readb(&uart->urxh) & 0xff);
}
/*
* Initialise the serial port with the given baudrate. The settings
* are always 8 data bits, no parity, 1 stop bit, no start bits.
*/
int serial_init_dev(const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
/* reset and enable FIFOs, set triggers to the maximum */
writel(0, &uart->ufcon);
writel(0, &uart->umcon);
/* 8N1 */
writel(0x3, &uart->ulcon);
/* No interrupts, no DMA, pure polling */
writel(0x245, &uart->ucon);
serial_setbrg_dev(dev_index);
return 0;
}
/*
* Output a single byte to the serial port.
*/
void serial_putc_dev(const char c, const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
/* wait for room in the tx FIFO */
while (!(readl(&uart->utrstat) & 0x2)) {
if (serial_err_check(dev_index, 1))
return;
}
writeb(c, &uart->utxh);
/* If \n, also do \r */
if (c == '\n')
serial_putc('\r');
}
void serial_setbrg_dev(const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
u32 uclk = get_uart_clk(dev_index);
u32 baudrate = gd->baudrate;
u32 val;
val = uclk / baudrate;
writel(val / 16 - 1, &uart->ubrdiv);
if (use_divslot)
writew(udivslot[val % 16], &uart->rest.slot);
else
writeb(val % 16, &uart->rest.value);
}
static int serial_err_check(const int dev_index, int op)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
unsigned int mask;
/*
* UERSTAT
* Break Detect [3]
* Frame Err [2] : receive operation
* Parity Err [1] : receive operation
* Overrun Err [0] : receive operation
*/
if (op)
mask = 0x8;
else
mask = 0xf;
return readl(&uart->uerstat) & mask;
}
/*
* Test whether a character is in the RX buffer
*/
int serial_tstc_dev(const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
return (int)(readl(&uart->utrstat) & 0x1);
}
