coreboot-kgpe-d16/payloads/libpayload/drivers/serial/s5p.c

107 lines
3.0 KiB
C

/*
* Copyright 2013 Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <libpayload.h>
#include <stdint.h>
struct s5p_uart
{
uint32_t ulcon; // line control
uint32_t ucon; // control
uint32_t ufcon; // FIFO control
uint32_t umcon; // modem control
uint32_t utrstat; // Tx/Rx status
uint32_t uerstat; // Rx error status
uint32_t ufstat; // FIFO status
uint32_t umstat; // modem status
uint32_t utxh; // transmit buffer
uint32_t urxh; // receive buffer
uint32_t ubrdiv; // baud rate divisor
uint32_t ufracval; // divisor fractional value
uint32_t uintp; // interrupt pending
uint32_t uints; // interrupt source
uint32_t uintm; // interrupt mask
};
static struct s5p_uart *uart_regs;
void serial_putchar(unsigned int c)
{
const uint32_t TxFifoFullBit = (0x1 << 24);
while (readl(&uart_regs->ufstat) & TxFifoFullBit)
{;}
writeb(c, &uart_regs->utxh);
if (c == '\n')
serial_putchar('\r');
}
int serial_havechar(void)
{
const uint32_t DataReadyMask = (0xf << 0) | (0x1 << 8);
return (readl(&uart_regs->ufstat) & DataReadyMask) != 0;
}
int serial_getchar(void)
{
while (!serial_havechar())
{;}
return readb(&uart_regs->urxh);
}
static struct console_output_driver s5p_serial_output =
{
.putchar = &serial_putchar
};
static struct console_input_driver s5p_serial_input =
{
.havekey = &serial_havechar,
.getchar = &serial_getchar
};
void serial_init(void)
{
if (!lib_sysinfo.serial || !lib_sysinfo.serial->baseaddr)
return;
uart_regs = (struct s5p_uart *)lib_sysinfo.serial->baseaddr;
}
void serial_console_init(void)
{
serial_init();
if (uart_regs) {
console_add_output_driver(&s5p_serial_output);
console_add_input_driver(&s5p_serial_input);
}
}