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| author | Matthew Garrett <mjg59@srcf.ucam.org> | 2013-01-20 10:24:26 +0000 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-02-02 00:01:14 +0100 |
| commit | c40a4518166b6c500c844579ec7069d4a0419f30 (patch) | |
| tree | 43295c9555e15bcba7ab2a3c12dd9ffc9f6fef87 /drivers/cpufreq/acpi-cpufreq.c | |
| parent | d5aaffa9dd531c978c6f3fea06a2972653bd7fc8 (diff) | |
| download | lwn-c40a4518166b6c500c844579ec7069d4a0419f30.tar.gz lwn-c40a4518166b6c500c844579ec7069d4a0419f30.zip | |
acpi-cpufreq: Do not load on K8
de3ed81d746d ("[CPUFREQ] Change link order of x86 cpufreq modules")
changed cpufreq drivers link order so that powernow-k8 gets loaded first
due to earlier K8s having BIOS bugs.
However, now that acpi-cpufreq supports both AMD and Intel CPUs with HW
P-states, we want to load it first, so that cases where acpi-cpufreq and
powernow-k8 are both built-in and powernow-k8 initializing first, can be
addressed.
So, make sure that even if acpi-cpufreq gets loaded first, it errors out
on K8s and powernow-k8 can be loaded then successfully.
Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
References: http://lkml.kernel.org/r/20130118162347.GA31499@srcf.ucam.org
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpufreq/acpi-cpufreq.c')
| -rw-r--r-- | drivers/cpufreq/acpi-cpufreq.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c index 7b0d49d78c61..22f9b47c5c74 100644 --- a/drivers/cpufreq/acpi-cpufreq.c +++ b/drivers/cpufreq/acpi-cpufreq.c @@ -762,6 +762,12 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) switch (perf->control_register.space_id) { case ACPI_ADR_SPACE_SYSTEM_IO: + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD && + boot_cpu_data.x86 == 0xf) { + pr_debug("AMD K8 systems must use native drivers.\n"); + result = -ENODEV; + goto err_unreg; + } pr_debug("SYSTEM IO addr space\n"); data->cpu_feature = SYSTEM_IO_CAPABLE; break; |