[PATCH 5/7] CPUFREQ: powernow-k8: Always compile powernow-k8 driver with ACPI support

From: Thomas Renninger
Date: Tue Feb 03 2009 - 11:48:02 EST


powernow-k8 driver should always try to get cpufreq info from ACPI.
Otherwise it will not be able to detect the transition latency correctly
which results in ondemand governor taking a wrong sampling rate which will
then result in sever performance loss.

Let the user not shoot himself in the foot and always compile in ACPI
support for powernow-k8.

This also fixes a wrong message if ACPI_PROCESSOR is compiled as a module and
#ifndef CONFIG_ACPI_PROCESSOR
path is chosen.

Signed-off-by: Thomas Renninger <trenn@xxxxxxx>
---
arch/x86/kernel/cpu/cpufreq/Kconfig | 19 ++-----------------
arch/x86/kernel/cpu/cpufreq/powernow-k8.c | 17 -----------------
arch/x86/kernel/cpu/cpufreq/powernow-k8.h | 5 +----
3 files changed, 3 insertions(+), 38 deletions(-)

diff --git a/arch/x86/kernel/cpu/cpufreq/Kconfig b/arch/x86/kernel/cpu/cpufreq/Kconfig
index efae3b2..b63b0db 100644
--- a/arch/x86/kernel/cpu/cpufreq/Kconfig
+++ b/arch/x86/kernel/cpu/cpufreq/Kconfig
@@ -87,30 +87,15 @@ config X86_POWERNOW_K7_ACPI
config X86_POWERNOW_K8
tristate "AMD Opteron/Athlon64 PowerNow!"
select CPU_FREQ_TABLE
+ depends on ACPI && ACPI_PROCESSOR
help
- This adds the CPUFreq driver for mobile AMD Opteron/Athlon64 processors.
+ This adds the CPUFreq driver for K8/K10 Opteron/Athlon64 processors.

To compile this driver as a module, choose M here: the
module will be called powernow-k8.

For details, take a look at <file:Documentation/cpu-freq/>.

- If in doubt, say N.
-
-config X86_POWERNOW_K8_ACPI
- bool
- prompt "ACPI Support" if X86_32
- depends on ACPI && X86_POWERNOW_K8 && ACPI_PROCESSOR
- depends on !(X86_POWERNOW_K8 = y && ACPI_PROCESSOR = m)
- default y
- help
- This provides access to the K8s Processor Performance States via ACPI.
- This driver is probably required for CPUFreq to work with multi-socket and
- SMP systems. It is not required on at least some single-socket yet
- multi-core systems, even if SMP is enabled.
-
- It is safe to say Y here.
-
config X86_GX_SUSPMOD
tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
depends on X86_32 && PCI
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
index fb039cd..9accffb 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
@@ -38,11 +38,9 @@
#include <asm/io.h>
#include <asm/delay.h>

-#ifdef CONFIG_X86_POWERNOW_K8_ACPI
#include <linux/acpi.h>
#include <linux/mutex.h>
#include <acpi/processor.h>
-#endif

#define PFX "powernow-k8: "
#define VERSION "version 2.20.00"
@@ -749,7 +747,6 @@ static int find_psb_table(struct powernow_k8_data *data)
return -ENODEV;
}

-#ifdef CONFIG_X86_POWERNOW_K8_ACPI
static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index)
{
if (!data->acpi_data.state_count || (cpu_family == CPU_HW_PSTATE))
@@ -953,13 +950,6 @@ static int get_transition_latency(struct powernow_k8_data *data)
return 1000 * max_latency;
}

-#else
-static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data) { return -ENODEV; }
-static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data) { return; }
-static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index) { return; }
-static int get_transition_latency(struct powernow_k8_data *data) { return 0; }
-#endif /* CONFIG_X86_POWERNOW_K8_ACPI */
-
/* Take a frequency, and issue the fid/vid transition command */
static int transition_frequency_fidvid(struct powernow_k8_data *data, unsigned int index)
{
@@ -1164,18 +1154,11 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol)
* an UP version, and is deprecated by AMD.
*/
if (num_online_cpus() != 1) {
-#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 FW_BUG 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
goto err_out;
}
if (pol->cpu != 0) {
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.h b/arch/x86/kernel/cpu/cpufreq/powernow-k8.h
index 8ecc75b..6c6698f 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.h
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.h
@@ -45,11 +45,10 @@ struct powernow_k8_data {
* frequency is in kHz */
struct cpufreq_frequency_table *powernow_table;

-#ifdef CONFIG_X86_POWERNOW_K8_ACPI
/* the acpi table needs to be kept. it's only available if ACPI was
* used to determine valid frequency/vid/fid states */
struct acpi_processor_performance acpi_data;
-#endif
+
/* we need to keep track of associated cores, but let cpufreq
* handle hotplug events - so just point at cpufreq pol->cpus
* structure */
@@ -222,10 +221,8 @@ static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid);

static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index);

-#ifdef CONFIG_X86_POWERNOW_K8_ACPI
static int fill_powernow_table_pstate(struct powernow_k8_data *data, struct cpufreq_frequency_table *powernow_table);
static int fill_powernow_table_fidvid(struct powernow_k8_data *data, struct cpufreq_frequency_table *powernow_table);
-#endif

#ifdef CONFIG_SMP
static inline void define_siblings(int cpu, cpumask_t cpu_sharedcore_mask[])
--
1.6.0.2

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