[PATCH v5 3/9] x86/intel_pstate: add a new driver interface, setpolicy()

[Wei Wang <wei.w.wang@intel.com>]

In order to better support future Intel processors, intel_pstate
changes to use percentage values to tune P-states. The setpolicy
driver interface is used to configure the intel_pstate internal
policy. The __cpufreq_set_policy needs to be intercepted to use
the setpolicy driver if it exists.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
---
 xen/drivers/cpufreq/utility.c      |  3 +++
 xen/include/acpi/cpufreq/cpufreq.h | 14 ++++++++++++++
 2 files changed, 17 insertions(+)

 changes in v5:
 1) delay the addition of the structures that are used in later patches.

diff --git a/xen/drivers/cpufreq/utility.c b/xen/drivers/cpufreq/utility.c
index 519f862..53879fe 100644
--- a/xen/drivers/cpufreq/utility.c
+++ b/xen/drivers/cpufreq/utility.c
@@ -456,6 +456,9 @@ int __cpufreq_set_policy(struct cpufreq_policy *data,
 
     data->min = policy->min;
     data->max = policy->max;
+    data->limits = policy->limits;
+    if (cpufreq_driver->setpolicy)
+        return cpufreq_driver->setpolicy(data);
 
     if (policy->governor != data->governor) {
         /* save old, working values */
diff --git a/xen/include/acpi/cpufreq/cpufreq.h b/xen/include/acpi/cpufreq/cpufreq.h
index f96c3e4..1ec04ca 100644
--- a/xen/include/acpi/cpufreq/cpufreq.h
+++ b/xen/include/acpi/cpufreq/cpufreq.h
@@ -41,6 +41,18 @@ struct cpufreq_cpuinfo {
     unsigned int        transition_latency; /* in 10^(-9) s = nanoseconds */
 };
 
+struct perf_limits {
+    bool_t no_turbo;
+    bool_t turbo_disabled;
+    uint32_t turbo_pct;
+    uint32_t max_perf_pct; /* max performance in percentage */
+    uint32_t min_perf_pct; /* min performance in percentage */
+    uint32_t max_perf;
+    uint32_t min_perf;
+    uint32_t max_policy_pct;
+    uint32_t min_policy_pct;
+};
+
 struct cpufreq_policy {
     cpumask_var_t       cpus;          /* affected CPUs */
     unsigned int        shared_type;   /* ANY or ALL affected CPUs
@@ -52,6 +64,7 @@ struct cpufreq_policy {
     unsigned int        max;    /* in kHz */
     unsigned int        cur;    /* in kHz, only needed if cpufreq
                                  * governors are used */
+    struct perf_limits  limits;
     struct cpufreq_governor     *governor;
 
     bool_t              resume; /* flag for cpufreq 1st run
@@ -145,6 +158,7 @@ struct cpufreq_driver {
     char   name[CPUFREQ_NAME_LEN];
     int    (*init)(struct cpufreq_policy *policy);
     int    (*verify)(struct cpufreq_policy *policy);
+    int    (*setpolicy)(struct cpufreq_policy *policy);
     int    (*update)(int cpuid, struct cpufreq_policy *policy);
     int    (*target)(struct cpufreq_policy *policy,
                      unsigned int target_freq,
-- 
1.9.1