embox

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/**
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 * @file
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 * @brief UART driver for ELVEES UART
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 * @author Denis Deryugin <deryugin.denis@gmail.com>
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 * @version 
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 * @date 14.11.2016
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 */
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#include <drivers/serial/uart_dev.h>
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#include <drivers/serial/diag_serial.h>
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#define UART(x)        (*(volatile uint32_t *)(dev->base_addr + (x)))
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#define RBR  0x00
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#define THR  0x00
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#define DLL  0x00
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#define DLH  0x04
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#define IER  0x04
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#define IIR  0x08
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#define FCR  0x08
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#define LCR  0x0C
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#define MCR  0x10
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#define LSR  0x14
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#define MSR  0x18
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#define SCR  0x1C
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#define SRBR 0x30
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#define STHR 0x30
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#define USR  0x7C
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#define TFL  0x80
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#define RFL  0x84
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#define SRR  0x88
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#define SRTS 0x8C
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#define SBCR 0x90
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#define SFE  0x98
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#define SRT  0x9C
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#define STET 0xA0
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#define HTX  0XA4
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#define USR_BUSY         (1 << 0)
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#define USR_TFNF         (1 << 1)
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#define LSR_RDR          (1 << 0)
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#define LSR_THRE         (1 << 5)
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#define LCR_DLAB         (1 << 7)
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#define IER_ERBFI        (1 << 0)
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#define LCR_DLS_8BITS    (3 << 0)
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static inline void  elvees_uart_setup_baud_rate(struct uart *dev, int baudrate_bps) {
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	uint32_t src_clock_hz = 48000000;
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    uint32_t divisor = (uint32_t) (src_clock_hz / (baudrate_bps * 16));
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    uint32_t tmp_lcr;
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    tmp_lcr = UART(LCR);
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    UART(LCR) = tmp_lcr | LCR_DLAB;
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    UART(DLH) =  (divisor >> 8) & 0xFF;
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    UART(DLL)= divisor & 0xFF;
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    UART(LCR) = tmp_lcr;
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}
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int elvees_uart_setup_common(struct uart *dev, const struct uart_params *params) {
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	UART(SRR) = 1; /* soft reset */
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	UART(FCR) = 0; /* without fifo */
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	UART(LCR) = LCR_DLS_8BITS; /* 8 bit */
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	elvees_uart_setup_baud_rate(dev, params->baud_rate);
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	/*enable rx interrupt*/
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	if (params->uart_param_flags & UART_PARAM_FLAGS_USE_IRQ) {
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		/*enable rx interrupt*/
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		UART(IER) = IER_ERBFI;
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	}
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	return 0;
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}
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int elvees_uart_has_symbol(struct uart *dev) {
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	return UART(LSR) & LSR_RDR;
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}
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int elvees_uart_getc(struct uart *dev) {
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	return (char)UART(RBR);
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}
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int elvees_uart_putc(struct uart *dev, int ch) {
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	while (!(UART(LSR) & LSR_THRE)) {
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	}
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	UART(THR) = ch;
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	return 0;
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}
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