lkml.org 
[lkml]   [2018]   [Apr]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] cpufreq: powernv: Remove global pstate ramp-down timer in POWER9
Date
POWER9 doesnot support global pstate requests for the chip. So remove
the timer logic which slowly ramps down the global pstate in P9
platforms.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
---
drivers/cpufreq/powernv-cpufreq.c | 23 ++++++++++++++++++-----
1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 0591874..71f8682 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -750,8 +750,13 @@ static int powernv_cpufreq_target_index(struct cpufreq_policy *policy,

cur_msec = jiffies_to_msecs(get_jiffies_64());

- spin_lock(&gpstates->gpstate_lock);
freq_data.pstate_id = idx_to_pstate(new_index);
+ if (!gpstates) {
+ freq_data.gpstate_id = freq_data.pstate_id;
+ goto no_gpstate;
+ }
+
+ spin_lock(&gpstates->gpstate_lock);

if (!gpstates->last_sampled_time) {
gpstate_idx = new_index;
@@ -801,6 +806,7 @@ static int powernv_cpufreq_target_index(struct cpufreq_policy *policy,

spin_unlock(&gpstates->gpstate_lock);

+no_gpstate:
/*
* Use smp_call_function to send IPI and execute the
* mtspr on target CPU. We could do that without IPI
@@ -835,6 +841,13 @@ static int powernv_cpufreq_cpu_init(struct cpufreq_policy *policy)
kernfs_put(kn);
}

+ policy->freq_table = powernv_freqs;
+ policy->fast_switch_possible = true;
+
+ if (pvr_version_is(PVR_POWER9))
+ return 0;
+
+ /* Initialise Gpstate ramp-down timer only on POWER8 */
gpstates = kzalloc(sizeof(*gpstates), GFP_KERNEL);
if (!gpstates)
return -ENOMEM;
@@ -849,15 +862,14 @@ static int powernv_cpufreq_cpu_init(struct cpufreq_policy *policy)
msecs_to_jiffies(GPSTATE_TIMER_INTERVAL);
spin_lock_init(&gpstates->gpstate_lock);

- policy->freq_table = powernv_freqs;
- policy->fast_switch_possible = true;
return 0;
}

static int powernv_cpufreq_cpu_exit(struct cpufreq_policy *policy)
{
/* timer is deleted in cpufreq_cpu_stop() */
- kfree(policy->driver_data);
+ if (policy->driver_data)
+ kfree(policy->driver_data);

return 0;
}
@@ -990,7 +1002,8 @@ static void powernv_cpufreq_stop_cpu(struct cpufreq_policy *policy)
freq_data.pstate_id = idx_to_pstate(powernv_pstate_info.min);
freq_data.gpstate_id = idx_to_pstate(powernv_pstate_info.min);
smp_call_function_single(policy->cpu, set_pstate, &freq_data, 1);
- del_timer_sync(&gpstates->timer);
+ if (gpstates)
+ del_timer_sync(&gpstates->timer);
}

static unsigned int powernv_fast_switch(struct cpufreq_policy *policy,
--
1.8.3.1
\
 
 \ /
  Last update: 2018-04-25 08:15    [W:0.061 / U:2.400 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site