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/*
* This file is part of the coreboot project.
*
* Copyright 2014 Rockchip Inc.
*
* 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; version 2 of the License.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <arch/io.h>
#include <boot/coreboot_tables.h>
#include <console/console.h> /* for __console definition */
#include <console/uart.h>
#include <drivers/uart/uart8250reg.h>
#include <stdint.h>
/*
* TODO: Use DRIVERS_UART_8250MEM driver instead.
* There is an issue in the IO call functions where x86 and ARM
* ordering is reversed. This 8250MEM driver uses the x86 convention.
* This driver can be replaced once the IO calls are sorted.
*/
struct rk3288_uart {
union {
uint32_t thr; /* Transmit holding register. */
uint32_t rbr; /* Receive buffer register. */
uint32_t dll; /* Divisor latch lsb. */
};
union {
uint32_t ier; /* Interrupt enable register. */
uint32_t dlm; /* Divisor latch msb. */
};
union {
uint32_t iir; /* Interrupt identification register. */
uint32_t fcr; /* FIFO control register. */
};
uint32_t lcr; /* Line control register. */
uint32_t mcr; /* Modem control register. */
uint32_t lsr; /* Line status register. */
uint32_t msr; /* Modem status register. */
uint32_t scr;
uint32_t reserved1[(0x30 - 0x20) / 4];
uint32_t srbr[(0x70 - 0x30) / 4];
uint32_t far;
uint32_t tfr;
uint32_t rfw;
uint32_t usr;
uint32_t tfl;
uint32_t rfl;
uint32_t srr;
uint32_t srts;
uint32_t sbcr;
uint32_t sdmam;
uint32_t sfe;
uint32_t srt;
uint32_t stet;
uint32_t htx;
uint32_t dmasa;
uint32_t reserver2[(0xf4 - 0xac) / 4];
uint32_t cpr;
uint32_t ucv;
uint32_t ctr;
} __attribute__ ((packed));
static struct rk3288_uart * const uart_ptr =
(void *)CONFIG_CONSOLE_SERIAL_UART_ADDRESS;
static void rk3288_uart_tx_flush(void);
static int rk3288_uart_tst_byte(void);
static void rk3288_uart_init(void)
{
/* FIXME: Use a hardcoded divisor for now.
* uint16_t divisor = (u16) uart_baudrate_divisor(default_baudrate(),
* uart_platform_refclk(), 16)
*/
const unsigned divisor = 13;
const uint8_t line_config = UART8250_LCR_WLS_8; // 8n1
rk3288_uart_tx_flush();
// Disable interrupts.
write32(&uart_ptr->ier, 0);
// Force DTR and RTS to high.
write32(&uart_ptr->mcr, UART8250_MCR_DTR | UART8250_MCR_RTS);
// Set line configuration, access divisor latches.
write32(&uart_ptr->lcr, UART8250_LCR_DLAB | line_config);
// Set the divisor.
write32(&uart_ptr->dll, divisor & 0xff);
write32(&uart_ptr->dlm, (divisor >> 8) & 0xff);
// Hide the divisor latches.
write32(&uart_ptr->lcr, line_config);
// Enable FIFOs, and clear receive and transmit.
write32(&uart_ptr->fcr, UART8250_FCR_FIFO_EN |
UART8250_FCR_CLEAR_RCVR | UART8250_FCR_CLEAR_XMIT);
}
static void rk3288_uart_tx_byte(unsigned char data)
{
while (!(read32(&uart_ptr->lsr) & UART8250_LSR_THRE));
write32(&uart_ptr->thr, data);
}
static void rk3288_uart_tx_flush(void)
{
while (!(read32(&uart_ptr->lsr) & UART8250_LSR_TEMT));
}
static unsigned char rk3288_uart_rx_byte(void)
{
if (!rk3288_uart_tst_byte())
return 0;
return read32(&uart_ptr->rbr);
}
static int rk3288_uart_tst_byte(void)
{
return (read32(&uart_ptr->lsr) & UART8250_LSR_DR) == UART8250_LSR_DR;
}
void uart_init(int idx)
{
rk3288_uart_init();
}
unsigned char uart_rx_byte(int idx)
{
return rk3288_uart_rx_byte();
}
void uart_tx_byte(int idx, unsigned char data)
{
rk3288_uart_tx_byte(data);
}
void uart_tx_flush(int idx)
{
rk3288_uart_tx_flush();
}
#ifndef __PRE_RAM__
void uart_fill_lb(void *data)
{
struct lb_serial serial;
serial.type = LB_SERIAL_TYPE_MEMORY_MAPPED;
serial.baseaddr = CONFIG_CONSOLE_SERIAL_UART_ADDRESS;
serial.baud = default_baudrate();
serial.regwidth = 1;
lb_add_serial(&serial, data);
lb_add_console(LB_TAG_CONSOLE_SERIAL8250MEM, data);
}
#endif
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