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From: Jiaxun Yang <jiaxun.yang@flygoat.com>
Date: Sat, 11 May 2024 17:00:08 +0100
Subject: [PATCH 1/7] MIPS: csrc-r4k: Refine rating computation
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Message-Id: <20240511-mips-clks-v1-1-ddb4a10ee9f9@flygoat.com>
References: <20240511-mips-clks-v1-0-ddb4a10ee9f9@flygoat.com>
In-Reply-To: <20240511-mips-clks-v1-0-ddb4a10ee9f9@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: linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, 
 Jiaxun Yang <jiaxun.yang@flygoat.com>

Increase frequency addend dividend to 100000000 (10MHz) to
reasonably accommodate multi GHz level mips_hpt_frequency.

Cap rating of csrc-r4k into 299 to ensure it doesn't go into
"Desired" range, given all the drama we have with CP0 count
registers (SMP sync, behaviour on wait etc).

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
---
 arch/mips/kernel/csrc-r4k.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/mips/kernel/csrc-r4k.c b/arch/mips/kernel/csrc-r4k.c
index edc4afc080fa..262896871351 100644
--- a/arch/mips/kernel/csrc-r4k.c
+++ b/arch/mips/kernel/csrc-r4k.c
@@ -111,7 +111,8 @@ int __init init_r4k_clocksource(void)
 		return -ENXIO;
 
 	/* Calculate a somewhat reasonable rating value */
-	clocksource_mips.rating = 200 + mips_hpt_frequency / 10000000;
+	clocksource_mips.rating = 200;
+	clocksource_mips.rating += clamp(mips_hpt_frequency / 100000000, 0, 99);
 
 	/*
 	 * R2 onwards makes the count accessible to user mode so it can be used

-- 
2.34.1