From c2f4a2c6e08c7635316dfd25ef706e9104384c56 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 8 Jul 2010 17:55:30 +0200 Subject: [PATCH] [CPUFREQ] powernow-k8: Limit Pstate transition latency check The Pstate transition latency check was added for broken F10h BIOSen which wrongly contain a value of 0 for transition and bus master latency. Fam11h and later, however, (will) have similar transition latency so extend that behavior for them too. Signed-off-by: Borislav Petkov Signed-off-by: Dave Jones --- arch/x86/kernel/cpu/cpufreq/powernow-k8.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c index 7ec2123838e6..3e90cce3dc8b 100644 --- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c +++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c @@ -1023,13 +1023,12 @@ static int get_transition_latency(struct powernow_k8_data *data) } if (max_latency == 0) { /* - * Fam 11h always returns 0 as transition latency. - * This is intended and means "very fast". While cpufreq core - * and governors currently can handle that gracefully, better - * set it to 1 to avoid problems in the future. - * For all others it's a BIOS bug. + * Fam 11h and later may return 0 as transition latency. This + * is intended and means "very fast". While cpufreq core and + * governors currently can handle that gracefully, better set it + * to 1 to avoid problems in the future. */ - if (boot_cpu_data.x86 != 0x11) + if (boot_cpu_data.x86 < 0x11) printk(KERN_ERR FW_WARN PFX "Invalid zero transition " "latency\n"); max_latency = 1; -- 2.20.1