cpufreq: powernv: Add boost files to export ultra-turbo frequencies

In P8+, Workload Optimized Frequency(WOF) provides the capability to
boost the cpu frequency based on the utilization of the other cpus
running in the chip. The On-Chip-Controller(OCC) firmware will control
the achievability of these frequencies depending on the power headroom
available in the chip. Currently the ultra-turbo frequencies provided
by this feature are exported along with the turbo and sub-turbo
frequencies as scaling_available_frequencies. This patch will export
the ultra-turbo frequencies separately as scaling_boost_frequencies in
WOF enabled systems. This patch will add the boost sysfs file which
can be used to disable/enable ultra-turbo frequencies.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 37671b54588030aae885e04c29b5076556223529..3ff5160451b436ec48511a9428ab611b2291b1f9 100644 (file)
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -144,6 +144,7 @@ static struct powernv_pstate_info {
        unsigned int max;
        unsigned int nominal;
        unsigned int nr_pstates;
+       bool wof_enabled;
 } powernv_pstate_info;
 
 /* Use following macros for conversions between pstate_id and index */
@@ -203,6 +204,7 @@ static int init_powernv_pstates(void)
        const __be32 *pstate_ids, *pstate_freqs;
        u32 len_ids, len_freqs;
        u32 pstate_min, pstate_max, pstate_nominal;
+       u32 pstate_turbo, pstate_ultra_turbo;
 
        power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
        if (!power_mgt) {
@@ -225,8 +227,29 @@ static int init_powernv_pstates(void)
                pr_warn("ibm,pstate-nominal not found\n");
                return -ENODEV;
        }
+
+       if (of_property_read_u32(power_mgt, "ibm,pstate-ultra-turbo",
+                                &pstate_ultra_turbo)) {
+               powernv_pstate_info.wof_enabled = false;
+               goto next;
+       }
+
+       if (of_property_read_u32(power_mgt, "ibm,pstate-turbo",
+                                &pstate_turbo)) {
+               powernv_pstate_info.wof_enabled = false;
+               goto next;
+       }
+
+       if (pstate_turbo == pstate_ultra_turbo)
+               powernv_pstate_info.wof_enabled = false;
+       else
+               powernv_pstate_info.wof_enabled = true;
+
+next:
        pr_info("cpufreq pstate min %d nominal %d max %d\n", pstate_min,
                pstate_nominal, pstate_max);
+       pr_info("Workload Optimized Frequency is %s in the platform\n",
+               (powernv_pstate_info.wof_enabled) ? "enabled" : "disabled");
 
        pstate_ids = of_get_property(power_mgt, "ibm,pstate-ids", &len_ids);
        if (!pstate_ids) {
@@ -268,6 +291,13 @@ static int init_powernv_pstates(void)
                        powernv_pstate_info.nominal = i;
                else if (id == pstate_min)
                        powernv_pstate_info.min = i;
+
+               if (powernv_pstate_info.wof_enabled && id == pstate_turbo) {
+                       int j;
+
+                       for (j = i - 1; j >= (int)powernv_pstate_info.max; j--)
+                               powernv_freqs[j].flags = CPUFREQ_BOOST_FREQ;
+               }
        }
 
        /* End of list marker entry */
@@ -305,9 +335,12 @@ static ssize_t cpuinfo_nominal_freq_show(struct cpufreq_policy *policy,
 struct freq_attr cpufreq_freq_attr_cpuinfo_nominal_freq =
        __ATTR_RO(cpuinfo_nominal_freq);
 
+#define SCALING_BOOST_FREQS_ATTR_INDEX         2
+
 static struct freq_attr *powernv_cpu_freq_attr[] = {
        &cpufreq_freq_attr_scaling_available_freqs,
        &cpufreq_freq_attr_cpuinfo_nominal_freq,
+       &cpufreq_freq_attr_scaling_boost_freqs,
        NULL,
 };
 
@@ -1013,11 +1046,22 @@ static int __init powernv_cpufreq_init(void)
        register_reboot_notifier(&powernv_cpufreq_reboot_nb);
        opal_message_notifier_register(OPAL_MSG_OCC, &powernv_cpufreq_opal_nb);
 
+       if (powernv_pstate_info.wof_enabled)
+               powernv_cpufreq_driver.boost_enabled = true;
+       else
+               powernv_cpu_freq_attr[SCALING_BOOST_FREQS_ATTR_INDEX] = NULL;
+
        rc = cpufreq_register_driver(&powernv_cpufreq_driver);
-       if (!rc)
-               return 0;
+       if (rc) {
+               pr_info("Failed to register the cpufreq driver (%d)\n", rc);
+               goto cleanup_notifiers;
+       }
 
-       pr_info("Failed to register the cpufreq driver (%d)\n", rc);
+       if (powernv_pstate_info.wof_enabled)
+               cpufreq_enable_boost_support();
+
+       return 0;
+cleanup_notifiers:
        unregister_all_notifiers();
        clean_chip_info();
 out: