From patchwork Mon Feb 2 05:10:31 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: preeti X-Patchwork-Id: 5759271 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id B5F719F336 for ; Mon, 2 Feb 2015 05:11:52 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9E12320266 for ; Mon, 2 Feb 2015 05:11:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7433C200E6 for ; Mon, 2 Feb 2015 05:11:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932668AbbBBFLs (ORCPT ); Mon, 2 Feb 2015 00:11:48 -0500 Received: from e32.co.us.ibm.com ([32.97.110.150]:54688 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752333AbbBBFLr (ORCPT ); Mon, 2 Feb 2015 00:11:47 -0500 Received: from /spool/local by e32.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Sun, 1 Feb 2015 22:11:45 -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 0C03419D8040; Sun, 1 Feb 2015 22:02:55 -0700 (MST) Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t125AEuc26542332; Sun, 1 Feb 2015 22:10:22 -0700 Received: from d03av03.boulder.ibm.com (localhost [127.0.0.1]) by d03av03.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t125B8c7005883; Sun, 1 Feb 2015 22:11:09 -0700 Received: from preeti.in.ibm.com (preeti.in.ibm.com [9.124.35.110] (may be forged)) by d03av03.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t125AuOX004734; Sun, 1 Feb 2015 22:11:00 -0700 Subject: [PATCH V3] 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: Mon, 02 Feb 2015 10:40:31 +0530 Message-ID: <20150202050821.24581.56186.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: 15020205-0005-0000-0000-0000087A3EE5 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 so as to avoid endianness transformation. Signed-off-by: Preeti U Murthy Acked-by: Stewart Smith --- Changes from V2: https://lkml.org/lkml/2015/1/27/1054 1. Used APIs to eliminate endianness transformation Changes from V1: https://lkml.org/lkml/2015/1/19/221 1. Used a better API for reading the DT property values. 2. Code cleanups arch/powerpc/platforms/powernv/setup.c | 37 ++++++++------ drivers/cpuidle/cpuidle-powernv.c | 86 ++++++++++++++++++-------------- 2 files changed, 71 insertions(+), 52 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/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c index b700a32..d6a9329 100644 --- a/arch/powerpc/platforms/powernv/setup.c +++ b/arch/powerpc/platforms/powernv/setup.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -409,37 +410,40 @@ static int __init pnv_init_idle_states(void) { struct device_node *power_mgt; int dt_idle_states; - const __be32 *idle_state_flags; - u32 len_flags, flags; + u32 *flags; int i; supported_cpuidle_states = 0; if (cpuidle_disable != IDLE_NO_OVERRIDE) - return 0; + goto out; if (!firmware_has_feature(FW_FEATURE_OPALv3)) - return 0; + goto out; power_mgt = of_find_node_by_path("/ibm,opal/power-mgt"); if (!power_mgt) { pr_warn("opal: PowerMgmt Node not found\n"); - return 0; + goto out; } - 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 0; + dt_idle_states = of_property_count_u32_elems(power_mgt, + "ibm,cpu-idle-state-flags"); + if (dt_idle_states < 0) { + pr_warn("cpuidle-powernv: no idle states found in the DT\n"); + goto out; } - dt_idle_states = len_flags / sizeof(u32); - - for (i = 0; i < dt_idle_states; i++) { - flags = be32_to_cpu(idle_state_flags[i]); - supported_cpuidle_states |= flags; + flags = kzalloc(sizeof(*flags) * dt_idle_states, GFP_KERNEL); + if (of_property_read_u32_array(power_mgt, + "ibm,cpu-idle-state-flags", flags, dt_idle_states)) { + pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-flags in DT\n"); + goto out_free; } + + for (i = 0; i < dt_idle_states; i++) + supported_cpuidle_states |= flags[i]; + if (!(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) { patch_instruction( (unsigned int *)pnv_fastsleep_workaround_at_entry, @@ -449,6 +453,9 @@ static int __init pnv_init_idle_states(void) PPC_INST_NOP); } pnv_alloc_idle_core_states(); +out_free: + kfree(flags); +out: return 0; } diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 223d505..2ef4b70 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include @@ -160,70 +161,81 @@ static int powernv_add_idle_states(void) struct device_node *power_mgt; 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 *latency_ns, *residency_ns, *flags; + 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); - if (!idle_state_flags) { - pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-flags\n"); - return nr_idle_states; + /* Read values of any property to determine the num of idle states */ + dt_idle_states = of_property_count_u32_elems(power_mgt, + "ibm,cpu-idle-state-flags"); + if (dt_idle_states < 0) { + pr_warn("cpuidle-powernv : no idle states found in the 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; + flags = kzalloc(sizeof(*flags) * dt_idle_states, GFP_KERNEL); + if (of_property_read_u32_array(power_mgt, + "ibm,cpu-idle-state-flags", flags, dt_idle_states)) { + pr_warn("cpuidle-powernv : missing ibm,cpu-idle-state-flags in DT\n"); + goto out_free_flags; } - dt_idle_states = len_flags / sizeof(u32); - - for (i = 0; i < dt_idle_states; i++) { + latency_ns = kzalloc(sizeof(*latency_ns) * dt_idle_states, GFP_KERNEL); + if (of_property_read_u32_array(power_mgt, + "ibm,cpu-idle-state-latencies-ns", latency_ns, dt_idle_states)) { + pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n"); + goto out_free_latency; + } - flags = be32_to_cpu(idle_state_flags[i]); + 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); - /* Cpuidle accepts exit_latency in us and we estimate - * target residency to be 10x exit_latency + for (i = 0; i < dt_idle_states; i++) { + /* + * 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) { + if (flags[i] & 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 || - flags & OPAL_PM_SLEEP_ENABLED_ER1) { + } else if (flags[i] & OPAL_PM_SLEEP_ENABLED || + flags[i] & 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_free_flags: + kfree(flags); +out: return nr_idle_states; }