u-boot/arch/mips/cpu/xburst/jz_serial.c
Xiangfu Liu 80421fcc3e MIPS: Ingenic XBurst Jz4740 processor support
Jz4740 is a multimedia application processor targeting for mobile
devices like e-Dictionary, eBook, portable media player (PMP) and
GPS navigator.  Jz4740 is powered by Ingenic 360 MHz XBurst CPU core
(JzRISC), in which RISC/SIMD/DSP hybrid instruction set architecture
provides high integration, high performance and low power consumption.

JzRISC incorporated in Jz4740 is the advanced and power-efficient
32-bit RISC core, compatible with MIPS32, with 16K I-Cache and 16K
D-Cache, and can operate at speeds up to 400 MHz.

On-chip modules such as LCD controller, embedded audio codec, multi-
channel SAR-ADC, AC97/I2S controller and camera I/F offer a rich
suite of peripherals for multimedia application.  NAND controller
(SLC/MLC), USB (host 1.1 and device 2.0), UART, I2C, SPI, etc. are
also available.

For more info about Ingenic XBurst Jz4740:
  http://en.ingenic.cn/eng/
  http://www.linux-mips.org/wiki/Ingenic

This patch introduces XBurst CPU support in U-Boot.  It's compatible
with MIPS32, but requires a bit different cache maintenance, timer
routines, and boot mechanism using USB boot tool, so XBurst support
can go into a separate new home, cpu/xburst/.

Signed-off-by: Xiangfu Liu <xiangfu@openmobilefree.net>
Acked-by: Daniel <zpxu@ingenic.cn>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
2011-10-10 22:06:12 +09:00

114 lines
2.6 KiB
C

/*
* Jz4740 UART support
* Copyright (c) 2011
* Qi Hardware, Xiangfu Liu <xiangfu@sharism.cc>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <config.h>
#include <common.h>
#include <asm/io.h>
#include <asm/jz4740.h>
/*
* serial_init - initialize a channel
*
* This routine initializes the number of data bits, parity
* and set the selected baud rate. Interrupts are disabled.
* Set the modem control signals if the option is selected.
*
* RETURNS: N/A
*/
struct jz4740_uart *uart = (struct jz4740_uart *)CONFIG_SYS_UART_BASE;
int serial_init(void)
{
/* Disable port interrupts while changing hardware */
writeb(0, &uart->dlhr_ier);
/* Disable UART unit function */
writeb(~UART_FCR_UUE, &uart->iir_fcr);
/* Set both receiver and transmitter in UART mode (not SIR) */
writeb(~(SIRCR_RSIRE | SIRCR_TSIRE), &uart->isr);
/*
* Set databits, stopbits and parity.
* (8-bit data, 1 stopbit, no parity)
*/
writeb(UART_LCR_WLEN_8 | UART_LCR_STOP_1, &uart->lcr);
/* Set baud rate */
serial_setbrg();
/* Enable UART unit, enable and clear FIFO */
writeb(UART_FCR_UUE | UART_FCR_FE | UART_FCR_TFLS | UART_FCR_RFLS,
&uart->iir_fcr);
return 0;
}
void serial_setbrg(void)
{
u32 baud_div, tmp;
baud_div = CONFIG_SYS_EXTAL / 16 / CONFIG_BAUDRATE;
tmp = readb(&uart->lcr);
tmp |= UART_LCR_DLAB;
writeb(tmp, &uart->lcr);
writeb((baud_div >> 8) & 0xff, &uart->dlhr_ier);
writeb(baud_div & 0xff, &uart->rbr_thr_dllr);
tmp &= ~UART_LCR_DLAB;
writeb(tmp, &uart->lcr);
}
int serial_tstc(void)
{
if (readb(&uart->lsr) & UART_LSR_DR)
return 1;
return 0;
}
void serial_putc(const char c)
{
if (c == '\n')
serial_putc('\r');
/* Wait for fifo to shift out some bytes */
while (!((readb(&uart->lsr) & (UART_LSR_TDRQ | UART_LSR_TEMT)) == 0x60))
;
writeb((u8)c, &uart->rbr_thr_dllr);
}
int serial_getc(void)
{
while (!serial_tstc())
;
return readb(&uart->rbr_thr_dllr);
}
void serial_puts(const char *s)
{
while (*s)
serial_putc(*s++);
}