From patchwork Tue Feb 3 06:20:14 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: preeti X-Patchwork-Id: 5766381 X-Patchwork-Delegate: rjw@sisk.pl Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 0F814BF440 for ; Tue, 3 Feb 2015 06:20:36 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id DBE1320A4C for ; Tue, 3 Feb 2015 06:20:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 19C4420A49 for ; Tue, 3 Feb 2015 06:20:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965321AbbBCGU1 (ORCPT ); Tue, 3 Feb 2015 01:20:27 -0500 Received: from e36.co.us.ibm.com ([32.97.110.154]:57066 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965118AbbBCGU0 (ORCPT ); Tue, 3 Feb 2015 01:20:26 -0500 Received: from /spool/local by e36.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 2 Feb 2015 23:20:26 -0700 Received: from d03dlp02.boulder.ibm.com (9.17.202.178) by e36.co.us.ibm.com (192.168.1.136) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Mon, 2 Feb 2015 23:20:24 -0700 Received: from b03cxnp08026.gho.boulder.ibm.com (b03cxnp08026.gho.boulder.ibm.com [9.17.130.18]) by d03dlp02.boulder.ibm.com (Postfix) with ESMTP id 6A5DE3E4003B; Mon, 2 Feb 2015 23:20:24 -0700 (MST) Received: from d03av05.boulder.ibm.com (d03av05.boulder.ibm.com [9.17.195.85]) by b03cxnp08026.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t136KlA632440532; Mon, 2 Feb 2015 23:20:47 -0700 Received: from d03av05.boulder.ibm.com (localhost [127.0.0.1]) by d03av05.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t136KNum010103; Mon, 2 Feb 2015 23:20:24 -0700 Received: from preeti.in.ibm.com (preeti.in.ibm.com [9.124.35.190] (may be forged)) by d03av05.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t136KGcK009662; Mon, 2 Feb 2015 23:20:21 -0700 Subject: [PATCH V4] cpuidle/powernv: Read target_residency value of idle states from DT if available From: Preeti U Murthy To: mpe@ellerman.id.au Cc: stewart@linux.vnet.ibm.com, rafael.j.wysocki@intel.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Date: Tue, 03 Feb 2015 11:50:14 +0530 Message-ID: <20150203061709.13097.7035.stgit@preeti.in.ibm.com> User-Agent: StGit/0.17-dirty MIME-Version: 1.0 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15020306-0021-0000-0000-000008428533 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html 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; }