From patchwork Mon Jan 19 11:32:51 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: preeti X-Patchwork-Id: 5658131 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 A0770C058D for ; Mon, 19 Jan 2015 11:33:07 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D1ECA20361 for ; Mon, 19 Jan 2015 11:33:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F39020253 for ; Mon, 19 Jan 2015 11:33:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751536AbbASLdD (ORCPT ); Mon, 19 Jan 2015 06:33:03 -0500 Received: from e32.co.us.ibm.com ([32.97.110.150]:56188 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751526AbbASLdC (ORCPT ); Mon, 19 Jan 2015 06:33:02 -0500 Received: from /spool/local by e32.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 19 Jan 2015 04:33:01 -0700 Received: from d03dlp03.boulder.ibm.com (9.17.202.179) by e32.co.us.ibm.com (192.168.1.132) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Mon, 19 Jan 2015 04:32:58 -0700 Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id F0A0319D8040; Mon, 19 Jan 2015 04:24:08 -0700 (MST) Received: from d03av04.boulder.ibm.com (d03av04.boulder.ibm.com [9.17.195.170]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t0JBVfEC27787302; Mon, 19 Jan 2015 04:31:41 -0700 Received: from d03av04.boulder.ibm.com (loopback [127.0.0.1]) by d03av04.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t0JBWujj010253; Mon, 19 Jan 2015 04:32:57 -0700 Received: from preeti.in.ibm.com (preeti.in.ibm.com [9.124.35.102] (may be forged)) by d03av04.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t0JBWqBs010069; Mon, 19 Jan 2015 04:32:54 -0700 Subject: [PATCH] cpuidle/powernv: Read target_residency value of idle states from DT if available From: Preeti U Murthy To: rafael.j.wysocki@intel.com Cc: linux-pm@vger.kernel.org, benh@kernel.crashing.org, linux-kernel@vger.kernel.org, mpe@ellerman.id.au, svaidy@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org Date: Mon, 19 Jan 2015 17:02:51 +0530 Message-ID: <20150119113251.23984.16931.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: 15011911-0005-0000-0000-00000824D594 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, clump the common parts of device tree parsing into one chunk. Signed-off-by: Preeti U Murthy --- drivers/cpuidle/cpuidle-powernv.c | 39 ++++++++++++++++++++++++------------- 1 file changed, 25 insertions(+), 14 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..9e732e1 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -162,7 +162,8 @@ static int powernv_add_idle_states(void) int dt_idle_states; const __be32 *idle_state_flags; const __be32 *idle_state_latency; - u32 len_flags, flags, latency_ns; + const __be32 *idle_state_residency; + u32 len_flags, flags, latency_ns, residency_ns; int i; /* Currently we have snooze statically defined */ @@ -186,14 +187,21 @@ static int powernv_add_idle_states(void) return nr_idle_states; } + idle_state_residency = of_get_property(power_mgt, + "ibm,cpu-idle-state-residency-ns", NULL); + if (!idle_state_residency) { + pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-residency-ns\n"); + pr_warn("Falling back to default values\n"); + } + dt_idle_states = len_flags / sizeof(u32); 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) { @@ -201,12 +209,8 @@ static int powernv_add_idle_states(void) 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 || @@ -215,13 +219,20 @@ static int powernv_add_idle_states(void) 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) / 1000; + + if (idle_state_residency) { + residency_ns = be32_to_cpu(idle_state_residency[i]); + powernv_states[nr_idle_states].target_residency = + ((unsigned int)residency_ns) / 1000; + } + + nr_idle_states++; } return nr_idle_states;