From a1531acd43310a7e4571d52e8846640667f4c74b Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Tue, 29 Jul 2008 22:32:58 -0700 Subject: [PATCH] cpufreq acpi: only call _PPC after cpufreq ACPI init funcs got called already Ingo Molnar provided a fix to not call _PPC at processor driver initialization time in "[PATCH] ACPI: fix cpufreq regression" (git commit e4233dec749a3519069d9390561b5636a75c7579) But it can still happen that _PPC is called at processor driver initialization time. This patch should make sure that this is not possible anymore. Signed-off-by: Thomas Renninger Cc: Andi Kleen Cc: Len Brown Cc: Dave Jones Cc: Ingo Molnar Cc: Venkatesh Pallipadi Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/powerpc/platforms/cell/cbe_cpufreq_pmi.c | 6 ++++++ drivers/acpi/processor_perflib.c | 15 +++++++++++++-- drivers/cpufreq/cpufreq.c | 3 +++ include/linux/cpufreq.h | 1 + 4 files changed, 23 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/platforms/cell/cbe_cpufreq_pmi.c b/arch/powerpc/platforms/cell/cbe_cpufreq_pmi.c index 69288f6531..3233fe84d1 100644 --- a/arch/powerpc/platforms/cell/cbe_cpufreq_pmi.c +++ b/arch/powerpc/platforms/cell/cbe_cpufreq_pmi.c @@ -96,6 +96,12 @@ static int pmi_notifier(struct notifier_block *nb, struct cpufreq_frequency_table *cbe_freqs; u8 node; + /* Should this really be called for CPUFREQ_ADJUST, CPUFREQ_INCOMPATIBLE + * and CPUFREQ_NOTIFY policy events?) + */ + if (event == CPUFREQ_START) + return 0; + cbe_freqs = cpufreq_frequency_get_table(policy->cpu); node = cbe_cpu_to_node(policy->cpu); diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c index b4749969c6..e98071a648 100644 --- a/drivers/acpi/processor_perflib.c +++ b/drivers/acpi/processor_perflib.c @@ -64,7 +64,13 @@ static DEFINE_MUTEX(performance_mutex); * policy is adjusted accordingly. */ -static unsigned int ignore_ppc = 0; +/* ignore_ppc: + * -1 -> cpufreq low level drivers not initialized -> _PSS, etc. not called yet + * ignore _PPC + * 0 -> cpufreq low level drivers initialized -> consider _PPC values + * 1 -> ignore _PPC totally -> forced by user through boot param + */ +static unsigned int ignore_ppc = -1; module_param(ignore_ppc, uint, 0644); MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \ "limited by BIOS, this should help"); @@ -72,7 +78,7 @@ MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \ #define PPC_REGISTERED 1 #define PPC_IN_USE 2 -static int acpi_processor_ppc_status = 0; +static int acpi_processor_ppc_status; static int acpi_processor_ppc_notifier(struct notifier_block *nb, unsigned long event, void *data) @@ -81,6 +87,11 @@ static int acpi_processor_ppc_notifier(struct notifier_block *nb, struct acpi_processor *pr; unsigned int ppc = 0; + if (event == CPUFREQ_START && ignore_ppc <= 0) { + ignore_ppc = 0; + return 0; + } + if (ignore_ppc) return 0; diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 8d6a3ff026..8a67f16987 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -825,6 +825,9 @@ static int cpufreq_add_dev(struct sys_device *sys_dev) policy->user_policy.min = policy->cpuinfo.min_freq; policy->user_policy.max = policy->cpuinfo.max_freq; + blocking_notifier_call_chain(&cpufreq_policy_notifier_list, + CPUFREQ_START, policy); + #ifdef CONFIG_SMP #ifdef CONFIG_HOTPLUG_CPU diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 2270ca5ec6..6fd5668aa5 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -106,6 +106,7 @@ struct cpufreq_policy { #define CPUFREQ_ADJUST (0) #define CPUFREQ_INCOMPATIBLE (1) #define CPUFREQ_NOTIFY (2) +#define CPUFREQ_START (3) #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ -- 2.39.5