linux-kernel - [PATCH] Crusoe: longrun cpufreq module reports false min freq

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Message-Id: <1210277401-14288-1-git-send-email-max@stro.at>
Date:	Thu,  8 May 2008 22:10:01 +0200
From:	maximilian attems <max@...o.at>
To:	James Bottomley <James.Bottomley@...eleye.com>
Cc:	Ingo Molnar <mingo@...e.hu>, linux-kernel@...r.kernel.org,
	maximilian attems <max@...o.at>,
	Kaz Sasayama <kazssym@...ercore.co.jp>
Subject: [PATCH] Crusoe: longrun cpufreq module reports false min freq

The longrun cpufreq module reports a false minimum frequency 3MHz on
300-600MHz Crusoe processor.  This may be due to a calculation bug
in the module.

Original patch from Kaz Sasayama <kazssym@...ercore.co.jp>
submitted as http://bugs.debian.org/468149 patch ported to x86

Cc: Kaz Sasayama <kazssym@...ercore.co.jp>
Signed-off-by: maximilian attems <max@...o.at>
---
 arch/x86/kernel/cpu/cpufreq/longrun.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/cpu/cpufreq/longrun.c b/arch/x86/kernel/cpu/cpufreq/longrun.c
index af4a867..777a7ff 100644
--- a/arch/x86/kernel/cpu/cpufreq/longrun.c
+++ b/arch/x86/kernel/cpu/cpufreq/longrun.c
@@ -245,7 +245,7 @@ static unsigned int __init longrun_determine_freqs(unsigned int *low_freq,
 	if ((ecx > 95) || (ecx == 0) || (eax < ebx))
 		return -EIO;
 
-	edx = (eax - ebx) / (100 - ecx);
+	edx = ((eax - ebx) * 100) / (100 - ecx);
 	*low_freq = edx * 1000; /* back to kHz */
 
 	dprintk("low frequency is %u kHz\n", *low_freq);
-- 
1.5.5.1

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