[CPUFREQ] powernow-k8: improve error messages
The most common error with powernow-k8 is an ACPI _PSS error
caused either by failure to load the ACPI processor module
or a bad parse of the _PSS object. Make the error message
returned to the user in these situations more straightforward
and easier to understand.
-Mark Langsdorf
Operating System Research Center
AMD
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
index 46d4034..206791e 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
@@ -1127,12 +1127,23 @@
* an UP version, and is deprecated by AMD.
*/
if (num_online_cpus() != 1) {
- printk(KERN_ERR PFX "MP systems not supported by PSB BIOS structure\n");
+#ifndef CONFIG_ACPI_PROCESSOR
+ printk(KERN_ERR PFX "ACPI Processor support is required "
+ "for SMP systems but is absent. Please load the "
+ "ACPI Processor module before starting this "
+ "driver.\n");
+#else
+ printk(KERN_ERR PFX "Your BIOS does not provide ACPI "
+ "_PSS objects in a way that Linux understands. "
+ "Please report this to the Linux ACPI maintainers"
+ " and complain to your BIOS vendor.\n");
+#endif
kfree(data);
return -ENODEV;
}
if (pol->cpu != 0) {
- printk(KERN_ERR PFX "No _PSS objects for CPU other than CPU0\n");
+ printk(KERN_ERR PFX "No ACPI _PSS objects for CPU other than "
+ "CPU0. Complain to your BIOS vendor.\n");
kfree(data);
return -ENODEV;
}