summaryrefslogtreecommitdiffstats
path: root/drivers/misc/ibmasm/uart.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/misc/ibmasm/uart.c')
-rw-r--r--drivers/misc/ibmasm/uart.c58
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);
+}