linuxdebug/drivers/misc/ibmasm/uart.c

59 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* IBM ASM Service Processor Device Driver
*
* Copyright (C) IBM Corporation, 2004
*
* Author: Max Asböck <amax@us.ibm.com>
*/
#include <linux/termios.h>
#include <linux/tty.h>
#include <linux/serial_core.h>
#include <linux/serial_reg.h>
#include <linux/serial_8250.h>
#include "ibmasm.h"
#include "lowlevel.h"
void ibmasm_register_uart(struct service_processor *sp)
{
struct uart_8250_port uart;
void __iomem *iomem_base;
iomem_base = sp->base_address + SCOUT_COM_B_BASE;
/* read the uart scratch register to determine if the UART
* is dedicated to the service processor or if the OS can use it
*/
if (0 == readl(iomem_base + UART_SCR)) {
dev_info(sp->dev, "IBM SP UART not registered, owned by service processor\n");
sp->serial_line = -1;
return;
}
memset(&uart, 0, sizeof(uart));
uart.port.irq = sp->irq;
uart.port.uartclk = 3686400;
uart.port.flags = UPF_SHARE_IRQ;
uart.port.iotype = UPIO_MEM;
uart.port.membase = iomem_base;
sp->serial_line = serial8250_register_8250_port(&uart);
if (sp->serial_line < 0) {
dev_err(sp->dev, "Failed to register serial port\n");
return;
}
enable_uart_interrupts(sp->base_address);
}
void ibmasm_unregister_uart(struct service_processor *sp)
{
if (sp->serial_line < 0)
return;
disable_uart_interrupts(sp->base_address);
serial8250_unregister_port(sp->serial_line);
}