tegrakernel/kernel/kernel-4.9/arch/tile/gxio/uart.c

88 lines
2.0 KiB
C

/*
* Copyright 2013 Tilera Corporation. All Rights Reserved.
*
* 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.
*
* 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, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*/
/*
* Implementation of UART gxio calls.
*/
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <gxio/uart.h>
#include <gxio/iorpc_globals.h>
#include <gxio/iorpc_uart.h>
#include <gxio/kiorpc.h>
int gxio_uart_init(gxio_uart_context_t *context, int uart_index)
{
char file[32];
int fd;
snprintf(file, sizeof(file), "uart/%d/iorpc", uart_index);
fd = hv_dev_open((HV_VirtAddr) file, 0);
if (fd < 0) {
if (fd >= GXIO_ERR_MIN && fd <= GXIO_ERR_MAX)
return fd;
else
return -ENODEV;
}
context->fd = fd;
/* Map in the MMIO space. */
context->mmio_base = (void __force *)
iorpc_ioremap(fd, HV_UART_MMIO_OFFSET, HV_UART_MMIO_SIZE);
if (context->mmio_base == NULL) {
hv_dev_close(context->fd);
context->fd = -1;
return -ENODEV;
}
return 0;
}
EXPORT_SYMBOL_GPL(gxio_uart_init);
int gxio_uart_destroy(gxio_uart_context_t *context)
{
iounmap((void __force __iomem *)(context->mmio_base));
hv_dev_close(context->fd);
context->mmio_base = NULL;
context->fd = -1;
return 0;
}
EXPORT_SYMBOL_GPL(gxio_uart_destroy);
/* UART register write wrapper. */
void gxio_uart_write(gxio_uart_context_t *context, uint64_t offset,
uint64_t word)
{
__gxio_mmio_write(context->mmio_base + offset, word);
}
EXPORT_SYMBOL_GPL(gxio_uart_write);
/* UART register read wrapper. */
uint64_t gxio_uart_read(gxio_uart_context_t *context, uint64_t offset)
{
return __gxio_mmio_read(context->mmio_base + offset);
}
EXPORT_SYMBOL_GPL(gxio_uart_read);