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From: Jiaxun Yang <jiaxun.yang@flygoat.com>
Date: Wed, 12 Jun 2024 09:54:29 +0100
Subject: [PATCH v2 2/7] MIPS: csrc-r4k: Apply verification clocksource
 flags
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Message-Id: <20240612-mips-clks-v2-2-a57e6f49f3db@flygoat.com>
References: <20240612-mips-clks-v2-0-a57e6f49f3db@flygoat.com>
In-Reply-To: <20240612-mips-clks-v2-0-a57e6f49f3db@flygoat.com>
To: Thomas Bogendoerfer <tsbogend@alpha.franken.de>, 
 Serge Semin <fancer.lancer@gmail.com>, 
 Daniel Lezcano <daniel.lezcano@linaro.org>, 
 Thomas Gleixner <tglx@linutronix.de>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>, linux-mips@vger.kernel.org, 
 linux-kernel@vger.kernel.org, Jiaxun Yang <jiaxun.yang@flygoat.com>

CP0 counter suffers from various problems like SMP sync,
behaviour on wait.

Set CLOCK_SOURCE_MUST_VERIFY and CLOCK_SOURCE_VERIFY_PERCPU,
as what x86 did to TSC, to let kernel test it before use.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
---
 arch/mips/kernel/csrc-r4k.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/mips/kernel/csrc-r4k.c b/arch/mips/kernel/csrc-r4k.c
index f02ae333f4f9..055747a7417d 100644
--- a/arch/mips/kernel/csrc-r4k.c
+++ b/arch/mips/kernel/csrc-r4k.c
@@ -21,7 +21,9 @@ static struct clocksource clocksource_mips = {
 	.name		= "MIPS",
 	.read		= c0_hpt_read,
 	.mask		= CLOCKSOURCE_MASK(32),
-	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS |
+				  CLOCK_SOURCE_MUST_VERIFY |
+				  CLOCK_SOURCE_VERIFY_PERCPU,
 };
 
 static u64 __maybe_unused notrace r4k_read_sched_clock(void)

-- 
2.43.0