From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- arch/powerpc/platforms/powernv/opal-kmsg.c | 47 ++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 arch/powerpc/platforms/powernv/opal-kmsg.c (limited to 'arch/powerpc/platforms/powernv/opal-kmsg.c') diff --git a/arch/powerpc/platforms/powernv/opal-kmsg.c b/arch/powerpc/platforms/powernv/opal-kmsg.c new file mode 100644 index 000000000..6c3bc4b4d --- /dev/null +++ b/arch/powerpc/platforms/powernv/opal-kmsg.c @@ -0,0 +1,47 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * kmsg dumper that ensures the OPAL console fully flushes panic messages + * + * Author: Russell Currey + * + * Copyright 2015 IBM Corporation. + */ + +#include + +#include +#include + +/* + * Console output is controlled by OPAL firmware. The kernel regularly calls + * OPAL_POLL_EVENTS, which flushes some console output. In a panic state, + * however, the kernel no longer calls OPAL_POLL_EVENTS and the panic message + * may not be completely printed. This function does not actually dump the + * message, it just ensures that OPAL completely flushes the console buffer. + */ +static void kmsg_dump_opal_console_flush(struct kmsg_dumper *dumper, + enum kmsg_dump_reason reason) +{ + /* + * Outside of a panic context the pollers will continue to run, + * so we don't need to do any special flushing. + */ + if (reason != KMSG_DUMP_PANIC) + return; + + opal_flush_console(0); +} + +static struct kmsg_dumper opal_kmsg_dumper = { + .dump = kmsg_dump_opal_console_flush +}; + +void __init opal_kmsg_init(void) +{ + int rc; + + /* Add our dumper to the list */ + rc = kmsg_dump_register(&opal_kmsg_dumper); + if (rc != 0) + pr_err("opal: kmsg_dump_register failed; returned %d\n", rc); +} -- cgit v1.2.3