diff options
Diffstat (limited to 'drivers/misc/ibmasm/uart.c')
| -rw-r--r-- | drivers/misc/ibmasm/uart.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/drivers/misc/ibmasm/uart.c b/drivers/misc/ibmasm/uart.c new file mode 100644 index 000000000..a5d4c8e01 --- /dev/null +++ b/drivers/misc/ibmasm/uart.c @@ -0,0 +1,58 @@ +// 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); +} |