zephyr/drivers/serial/nsim_uart.c

82 lines
2.7 KiB
C

/*
* Copyright (c) 2014-2015, Wind River Systems, 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) Neither the name of Wind River Systems nor the names of its contributors
* may be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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 <nanokernel.h>
#include <arch/cpu.h>
#include <sections.h>
#include <misc/__assert.h>
#include <stdint.h>
#include <misc/util.h>
#include <string.h>
#include <board.h>
#include <drivers/uart.h>
#define NSIM_UART_DATA 0
#define NSIM_UART_STATUS 1
#define DATA_REG(n) (uart[n].regs + NSIM_UART_DATA)
#define STATUS_REG(n) (uart[n].regs + NSIM_UART_STATUS)
#define TXEMPTY 0x80 /* Transmit FIFO empty and next character can be sent */
struct uart {
uint32_t regs; /* MM base address */
};
static struct uart __noinit uart[CONFIG_UART_NUM_SYSTEM_PORTS];
/*
* uart_init - initialize fake serial port
* @which: port number
* @init_info: pointer to initialization information
*/
void uart_init(int which, const struct uart_init_info * const init_info)
{
int key = irq_lock();
uart[which].regs = init_info->regs;
irq_unlock(key);
}
/*
* uart_poll_out - output a character to serial port
* @port: port number
* @c: character to output
*/
unsigned char uart_poll_out(int port, unsigned char c)
{
/* wait for transmitter to ready to accept a character */
while ((_arc_v2_aux_reg_read(STATUS_REG(port)) & TXEMPTY) == 0)
;
_arc_v2_aux_reg_write(DATA_REG(port), c);
return c;
}