u-boot/arch/sparc/cpu/leon2/serial.c

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/* GRLIB APBUART Serial controller driver
*
* (C) Copyright 2008
* Daniel Hellstrom, Gaisler Research, daniel@gaisler.com.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/processor.h>
#include <asm/leon.h>
#include <serial.h>
#include <linux/compiler.h>
DECLARE_GLOBAL_DATA_PTR;
static int leon2_serial_init(void)
{
LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
LEON2_Uart_regs *regs;
unsigned int tmp;
/* Init LEON2 UART
*
* Set scaler / baud rate
*
* Receiver & transmitter enable
*/
#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
#else
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
#endif
regs->UART_Scaler = CONFIG_SYS_LEON2_UART1_SCALER;
/* Let bit 11 be unchanged (debug bit for GRMON) */
tmp = READ_WORD(regs->UART_Control);
regs->UART_Control = ((tmp & LEON2_UART_CTRL_DBG) |
(LEON2_UART1_LOOPBACK_ENABLE << 7) |
(LEON2_UART1_FLOWCTRL_ENABLE << 6) |
(LEON2_UART1_PARITY_ENABLE << 5) |
(LEON2_UART1_ODDPAR_ENABLE << 4) |
LEON2_UART_CTRL_RE | LEON2_UART_CTRL_TE);
return 0;
}
static void leon2_serial_putc_raw(const char c)
{
LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
LEON2_Uart_regs *regs;
#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
#else
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
#endif
/* Wait for last character to go. */
while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_THE)) ;
/* Send data */
regs->UART_Channel = c;
#ifdef LEON_DEBUG
/* Wait for data to be sent */
while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_TSE)) ;
#endif
}
static void leon2_serial_putc(const char c)
{
if (c == '\n')
leon2_serial_putc_raw('\r');
leon2_serial_putc_raw(c);
}
static int leon2_serial_getc(void)
{
LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
LEON2_Uart_regs *regs;
#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
#else
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
#endif
/* Wait for a character to arrive. */
while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_DR)) ;
/* read data */
return READ_WORD(regs->UART_Channel);
}
static int leon2_serial_tstc(void)
{
LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
LEON2_Uart_regs *regs;
#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
#else
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
#endif
return (READ_WORD(regs->UART_Status) & LEON2_UART_STAT_DR);
}
/* set baud rate for uart */
static void leon2_serial_setbrg(void)
{
/* update baud rate settings, read it from gd->baudrate */
unsigned int scaler;
LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS;
LEON2_Uart_regs *regs;
#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1;
#else
regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2;
#endif
if (gd->baudrate > 0) {
scaler =
(((CONFIG_SYS_CLK_FREQ * 10) / (gd->baudrate * 8)) -
5) / 10;
regs->UART_Scaler = scaler;
}
}
static struct serial_device leon2_serial_drv = {
.name = "leon2_serial",
.start = leon2_serial_init,
.stop = NULL,
.setbrg = leon2_serial_setbrg,
.putc = leon2_serial_putc,
.puts = default_serial_puts,
.getc = leon2_serial_getc,
.tstc = leon2_serial_tstc,
};
void leon2_serial_initialize(void)
{
serial_register(&leon2_serial_drv);
}
__weak struct serial_device *default_serial_console(void)
{
return &leon2_serial_drv;
}