From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754720AbbBQIAP (ORCPT ); Tue, 17 Feb 2015 03:00:15 -0500 Received: from e39.co.us.ibm.com ([32.97.110.160]:54113 "EHLO e39.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752337AbbBQIAN (ORCPT ); Tue, 17 Feb 2015 03:00:13 -0500 Message-ID: <54E2F4CE.2090205@linux.vnet.ibm.com> Date: Tue, 17 Feb 2015 13:29:10 +0530 From: Preeti U Murthy User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: mpe@ellerman.id.au, rafael.j.wysocki@intel.com CC: stewart@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: [PATCH V4] cpuidle/powernv: Read target_residency value of idle states from DT if available References: <20150203061709.13097.7035.stgit@preeti.in.ibm.com> In-Reply-To: <20150203061709.13097.7035.stgit@preeti.in.ibm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15021708-0033-0000-0000-000003AF1D9D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Rafael, Can you please pull this patch ? Another patch based on top of this is waiting to be pulled: [PATCH] driver/cpuidle-powernv: Avoid endianness conversions while parsing DT Regards Preeti U Murthy On 02/03/2015 11:50 AM, Preeti U Murthy wrote: > The device tree now exposes the residency values for different idle states. Read > these values instead of calculating residency from the latency values. The values > exposed in the DT are validated for optimal power efficiency. However to maintain > compatibility with the older firmware code which does not expose residency > values, use default values as a fallback mechanism. While at it, use better > APIs to parse the powermgmt device tree node. > > Signed-off-by: Preeti U Murthy > Acked-by: Stewart Smith > Acked-by: Michael Ellerman > --- > Changes from the previous versions: https://lkml.org/lkml/2015/2/2/12 > 1. Used better APIs > 2. Code Cleanups > 3. Reverted back to the V2 of this patch as suggested in the above link, > in addition to a few cleanups and carried forward the Acks from V2 > > drivers/cpuidle/cpuidle-powernv.c | 71 ++++++++++++++++++++++--------------- > 1 file changed, 42 insertions(+), 29 deletions(-) > > diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c > index 2726663..3aa27a0 100644 > --- a/drivers/cpuidle/cpuidle-powernv.c > +++ b/drivers/cpuidle/cpuidle-powernv.c > @@ -13,6 +13,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -161,69 +162,81 @@ static int powernv_add_idle_states(void) > int nr_idle_states = 1; /* Snooze */ > int dt_idle_states; > const __be32 *idle_state_flags; > - const __be32 *idle_state_latency; > - u32 len_flags, flags, latency_ns; > - int i; > + u32 len_flags, flags; > + u32 *latency_ns, *residency_ns; > + int i, rc; > > /* Currently we have snooze statically defined */ > > power_mgt = of_find_node_by_path("/ibm,opal/power-mgt"); > if (!power_mgt) { > pr_warn("opal: PowerMgmt Node not found\n"); > - return nr_idle_states; > + goto out; > } > > - idle_state_flags = of_get_property(power_mgt, "ibm,cpu-idle-state-flags", &len_flags); > + idle_state_flags = of_get_property(power_mgt, > + "ibm,cpu-idle-state-flags", &len_flags); > if (!idle_state_flags) { > - pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-flags\n"); > - return nr_idle_states; > + pr_warn("cpuidle-powernv : missing > + ibm,cpu-idle-state-flags in DT\n"); > + goto out; > } > > - idle_state_latency = of_get_property(power_mgt, > - "ibm,cpu-idle-state-latencies-ns", NULL); > - if (!idle_state_latency) { > - pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-latencies-ns\n"); > - return nr_idle_states; > + dt_idle_states = len_flags / sizeof(u32); > + > + latency_ns = kzalloc(sizeof(*latency_ns) * dt_idle_states, GFP_KERNEL); > + rc = of_property_read_u32_array(power_mgt, > + "ibm,cpu-idle-state-latencies-ns", latency_ns, dt_idle_states); > + if (rc) { > + pr_warn("cpuidle-powernv: missing > + ibm,cpu-idle-state-latencies-ns in DT\n"); > + goto out_free_latency; > } > > - dt_idle_states = len_flags / sizeof(u32); > + residency_ns = kzalloc(sizeof(*residency_ns) * dt_idle_states, GFP_KERNEL); > + rc = of_property_read_u32_array(power_mgt, > + "ibm,cpu-idle-state-residency-ns", residency_ns, dt_idle_states); > > for (i = 0; i < dt_idle_states; i++) { > > flags = be32_to_cpu(idle_state_flags[i]); > > - /* Cpuidle accepts exit_latency in us and we estimate > - * target residency to be 10x exit_latency > + /* > + * Cpuidle accepts exit_latency and target_residency in us. > + * Use default target_residency values if f/w does not expose it. > */ > - latency_ns = be32_to_cpu(idle_state_latency[i]); > if (flags & OPAL_PM_NAP_ENABLED) { > /* Add NAP state */ > strcpy(powernv_states[nr_idle_states].name, "Nap"); > strcpy(powernv_states[nr_idle_states].desc, "Nap"); > powernv_states[nr_idle_states].flags = 0; > - powernv_states[nr_idle_states].exit_latency = > - ((unsigned int)latency_ns) / 1000; > - powernv_states[nr_idle_states].target_residency = > - ((unsigned int)latency_ns / 100); > + powernv_states[nr_idle_states].target_residency = 100; > powernv_states[nr_idle_states].enter = &nap_loop; > - nr_idle_states++; > - } > - > - if (flags & OPAL_PM_SLEEP_ENABLED || > + } else if (flags & OPAL_PM_SLEEP_ENABLED || > flags & OPAL_PM_SLEEP_ENABLED_ER1) { > /* Add FASTSLEEP state */ > strcpy(powernv_states[nr_idle_states].name, "FastSleep"); > strcpy(powernv_states[nr_idle_states].desc, "FastSleep"); > powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIMER_STOP; > - powernv_states[nr_idle_states].exit_latency = > - ((unsigned int)latency_ns) / 1000; > - powernv_states[nr_idle_states].target_residency = > - ((unsigned int)latency_ns / 100); > + powernv_states[nr_idle_states].target_residency = 300000; > powernv_states[nr_idle_states].enter = &fastsleep_loop; > - nr_idle_states++; > } > + > + powernv_states[nr_idle_states].exit_latency = > + ((unsigned int)latency_ns[i]) / 1000; > + > + if (!rc) { > + powernv_states[nr_idle_states].target_residency = > + ((unsigned int)residency_ns[i]) / 1000; > + } > + > + nr_idle_states++; > } > > + kfree(residency_ns); > +out_free_latency: > + kfree(latency_ns); > +out: > return nr_idle_states; > } > > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev >