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1// SPDX-License-Identifier: GPL-2.0-or-later2 3/*4 * IBM ASM Service Processor Device Driver5 *6 * Copyright (C) IBM Corporation, 20047 *8 * Author: Max Asböck <amax@us.ibm.com>9 */10 11#include <linux/termios.h>12#include <linux/tty.h>13#include <linux/serial_core.h>14#include <linux/serial_reg.h>15#include <linux/serial_8250.h>16#include "ibmasm.h"17#include "lowlevel.h"18 19 20void ibmasm_register_uart(struct service_processor *sp)21{22 struct uart_8250_port uart;23 void __iomem *iomem_base;24 25 iomem_base = sp->base_address + SCOUT_COM_B_BASE;26 27 /* read the uart scratch register to determine if the UART28 * is dedicated to the service processor or if the OS can use it29 */30 if (0 == readl(iomem_base + UART_SCR)) {31 dev_info(sp->dev, "IBM SP UART not registered, owned by service processor\n");32 sp->serial_line = -1;33 return;34 }35 36 memset(&uart, 0, sizeof(uart));37 uart.port.irq = sp->irq;38 uart.port.uartclk = 3686400;39 uart.port.flags = UPF_SHARE_IRQ;40 uart.port.iotype = UPIO_MEM;41 uart.port.membase = iomem_base;42 43 sp->serial_line = serial8250_register_8250_port(&uart);44 if (sp->serial_line < 0) {45 dev_err(sp->dev, "Failed to register serial port\n");46 return;47 }48 enable_uart_interrupts(sp->base_address);49}50 51void ibmasm_unregister_uart(struct service_processor *sp)52{53 if (sp->serial_line < 0)54 return;55 56 disable_uart_interrupts(sp->base_address);57 serial8250_unregister_port(sp->serial_line);58}59