From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x242.google.com (mail-pf0-x242.google.com [IPv6:2607:f8b0:400e:c00::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40KK0k63ptzDrZf for ; Mon, 9 Apr 2018 15:41:10 +1000 (AEST) Received: by mail-pf0-x242.google.com with SMTP id l27so5226247pfk.12 for ; Sun, 08 Apr 2018 22:41:10 -0700 (PDT) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Cc: Nicholas Piggin , Russell Currey Subject: [PATCH 1/6] powerpc/powernv: opal-kmsg use flush fallback from console code Date: Mon, 9 Apr 2018 15:40:51 +1000 Message-Id: <20180409054056.27292-2-npiggin@gmail.com> In-Reply-To: <20180409054056.27292-1-npiggin@gmail.com> References: <20180409054056.27292-1-npiggin@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Use the more refined and tested event polling loop from opal_put_chars as the fallback console flush in the opal-kmsg path. This loop is used by the console driver today, whereas the opal-kmsg fallback is not likely to have been used for years. Use WARN_ONCE rather than a printk when the fallback is invoked to prepare for moving the console flush into a common function. Cc: Russell Currey Signed-off-by: Nicholas Piggin --- arch/powerpc/platforms/powernv/opal-kmsg.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/arch/powerpc/platforms/powernv/opal-kmsg.c b/arch/powerpc/platforms/powernv/opal-kmsg.c index f8f41ccce75f..fd2bbf4fd6dc 100644 --- a/arch/powerpc/platforms/powernv/opal-kmsg.c +++ b/arch/powerpc/platforms/powernv/opal-kmsg.c @@ -51,20 +51,17 @@ static void force_opal_console_flush(struct kmsg_dumper *dumper, } while (rc == OPAL_PARTIAL); /* More to flush */ } else { - int i; + __be64 evt; + WARN_ONCE(1, "opal: OPAL_CONSOLE_FLUSH missing.\n"); /* * If OPAL_CONSOLE_FLUSH is not implemented in the firmware, * the console can still be flushed by calling the polling - * function enough times to flush the buffer. We don't know - * how much output still needs to be flushed, but we can be - * generous since the kernel is in panic and doesn't need - * to do much else. + * function while it has OPAL_EVENT_CONSOLE_OUTPUT events. */ - printk(KERN_NOTICE "opal: OPAL_CONSOLE_FLUSH missing.\n"); - for (i = 0; i < 1024; i++) { - opal_poll_events(NULL); - } + do { + opal_poll_events(&evt); + } while (be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT); } } -- 2.17.0