From: Matthew Garrett <[email protected]> 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 <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Borislav Petkov <[email protected]> --- drivers/cpufreq/acpi-cpufreq.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c index 0d048f6a2b23..31b06bbab54c 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; -- 1.8.1.rc3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
