From 354aeeb1ca8f82ea133ede21987034addc75057a Mon Sep 17 00:00:00 2001 From: Jesse Barnes Date: Thu, 23 Sep 2010 23:49:28 +0200 Subject: [PATCH] IPS driver: don't toggle CPU turbo on unsupported CPUs If the CPU doesn't support turbo, don't try to enable/disable it. http://bugzilla.kernel.org/show_bug.cgi?id=18742 Signed-off-by: Jesse Barnes Signed-off-by: Matthew Garrett --- drivers/platform/x86/intel_ips.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/platform/x86/intel_ips.c b/drivers/platform/x86/intel_ips.c index bfa9c726054a..71d04ef47b8c 100644 --- a/drivers/platform/x86/intel_ips.c +++ b/drivers/platform/x86/intel_ips.c @@ -51,7 +51,6 @@ * TODO: * - handle CPU hotplug * - provide turbo enable/disable api - * - make sure we can write turbo enable/disable reg based on MISC_EN * * Related documents: * - CDI 403777, 403778 - Auburndale EDS vol 1 & 2 @@ -325,6 +324,7 @@ struct ips_driver { bool gpu_preferred; bool poll_turbo_status; bool second_cpu; + bool turbo_toggle_allowed; struct ips_mcp_limits *limits; /* Optional MCH interfaces for if i915 is in use */ @@ -461,7 +461,8 @@ static void ips_enable_cpu_turbo(struct ips_driver *ips) if (ips->__cpu_turbo_on) return; - on_each_cpu(do_enable_cpu_turbo, ips, 1); + if (ips->turbo_toggle_allowed) + on_each_cpu(do_enable_cpu_turbo, ips, 1); ips->__cpu_turbo_on = true; } @@ -498,7 +499,8 @@ static void ips_disable_cpu_turbo(struct ips_driver *ips) if (!ips->__cpu_turbo_on) return; - on_each_cpu(do_disable_cpu_turbo, ips, 1); + if (ips->turbo_toggle_allowed) + on_each_cpu(do_disable_cpu_turbo, ips, 1); ips->__cpu_turbo_on = false; } @@ -1332,8 +1334,10 @@ static struct ips_mcp_limits *ips_detect_cpu(struct ips_driver *ips) * turbo manually or we'll get an illegal MSR access, even though * turbo will still be available. */ - if (!(misc_en & IA32_MISC_TURBO_EN)) - ; /* add turbo MSR write allowed flag if necessary */ + if (misc_en & IA32_MISC_TURBO_EN) + ips->turbo_toggle_allowed = true; + else + ips->turbo_toggle_allowed = false; if (strstr(boot_cpu_data.x86_model_id, "CPU M")) limits = &ips_sv_limits; -- 2.30.2