From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bruno Ducrot Subject: Re: powernow-k8 problem Date: Thu, 10 Mar 2005 17:51:02 +0100 Message-ID: <20050310165102.GA2298@poupinou.org> References: <007d01c520b1$bce2d650$0d010a0a@RED> Mime-Version: 1.0 Content-Disposition: inline In-Reply-To: <007d01c520b1$bce2d650$0d010a0a@RED> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cpufreq-bounces@lists.linux.org.uk Errors-To: cpufreq-bounces+glkc-cpufreq=gmane.org@lists.linux.org.uk Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: red@you.sk, paul.devriendt@amd.com Cc: cpufreq@ZenII.linux.org.uk On Fri, Mar 04, 2005 at 01:00:19PM +0100, red@you.sk wrote: > Hello list, > i would like to ask if it`s workaround for powernow-k8 to be fuctional on AMD64 system with FSB >254Mhz. Any value bigger than 254 causing powernow-k8 module to refuse load with message "No such device". Changing only value FSB in bios to any value <=254 make powernow-k8 work fine again. > My board is abit av8 and CPU is AMD64 3000+. > I don't know if such workaround exist but I know for sure you should change the PLL_LOCK_CONVERSION in the powernow_k8.h for stability reason if you try to make one, because the processor use a speical counter clocked by the system bus in order to prevent snoop when the PLL lock and therefore you should give it a good one since the current powernow_k8 driver is written with a fsb at 200MHz in mind. With a FSB to (say) 254 MHz, I would put something like that: #define PLL_LOCK_CONVERSION 254 I guess a proper fix should be to do so by computing the system bus and then pass this value instead of using PLL_LOCK_CONVERSION since it seems there are more and more people that want to run their system with a custom fsb. Paul, could you please give us some coments? Cheers, -- Bruno Ducrot -- Which is worse: ignorance or apathy? -- Don't know. Don't care.