From patchwork Thu Jul 7 20:47:11 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Shreyas B. Prabhu" X-Patchwork-Id: 9219629 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 231D0607D9 for ; Thu, 7 Jul 2016 20:49:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1282528559 for ; Thu, 7 Jul 2016 20:49:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0445D2855B; Thu, 7 Jul 2016 20:49:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5925128559 for ; Thu, 7 Jul 2016 20:49:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752844AbcGGUtK (ORCPT ); Thu, 7 Jul 2016 16:49:10 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:58175 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753306AbcGGUsH (ORCPT ); Thu, 7 Jul 2016 16:48:07 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u67KiwAk027280 for ; Thu, 7 Jul 2016 16:48:06 -0400 Received: from e19.ny.us.ibm.com (e19.ny.us.ibm.com [129.33.205.209]) by mx0a-001b2d01.pphosted.com with ESMTP id 2415xmb11k-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 07 Jul 2016 16:48:06 -0400 Received: from localhost by e19.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 7 Jul 2016 16:48:05 -0400 Received: from d01dlp01.pok.ibm.com (9.56.250.166) by e19.ny.us.ibm.com (146.89.104.206) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Thu, 7 Jul 2016 16:48:02 -0400 X-IBM-Helo: d01dlp01.pok.ibm.com X-IBM-MailFrom: shreyas@linux.vnet.ibm.com Received: from b01cxnp22035.gho.pok.ibm.com (b01cxnp22035.gho.pok.ibm.com [9.57.198.25]) by d01dlp01.pok.ibm.com (Postfix) with ESMTP id BFC2638C804F; Thu, 7 Jul 2016 16:48:01 -0400 (EDT) Received: from b01ledav006.gho.pok.ibm.com (b01ledav006.gho.pok.ibm.com [9.57.199.111]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u67Km17j58130526; Thu, 7 Jul 2016 20:48:01 GMT Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8F519AC03A; Thu, 7 Jul 2016 16:48:01 -0400 (EDT) Received: from flexbl0cb.in.ibm.com (unknown [9.121.59.78]) by b01ledav006.gho.pok.ibm.com (Postfix) with ESMTP id 2C815AC057; Thu, 7 Jul 2016 16:47:57 -0400 (EDT) From: "Shreyas B. Prabhu" To: mpe@ellerman.id.au Cc: benh@au1.ibm.com, paulus@ozlabs.org, mikey@neuling.org, ego@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, maddy@linux.vnet.ibm.com, "Shreyas B. Prabhu" , "Rafael J. Wysocki" , Daniel Lezcano , Rob Herring , Lorenzo Pieralisi , linux-pm@vger.kernel.org Subject: [PATCH v7 10/11] cpuidle/powernv: Add support for POWER ISA v3 idle states Date: Fri, 8 Jul 2016 02:17:11 +0530 X-Mailer: git-send-email 2.4.11 In-Reply-To: <1467924432-29003-1-git-send-email-shreyas@linux.vnet.ibm.com> References: <1467924432-29003-1-git-send-email-shreyas@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16070720-0056-0000-0000-000000BA1A8A X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16070720-0057-0000-0000-000004D41F45 Message-Id: <1467924432-29003-11-git-send-email-shreyas@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2016-07-07_10:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1607070184 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP POWER ISA v3 defines a new idle processor core mechanism. In summary, a) new instruction named stop is added. b) new per thread SPR named PSSCR is added which controls the behavior of stop instruction. Supported idle states and value to be written to PSSCR register to enter any idle state is exposed via ibm,cpu-idle-state-names and ibm,cpu-idle-state-psscr respectively. To enter an idle state, platform provided power_stop() needs to be invoked with the appropriate PSSCR value. This patch adds support for this new mechanism in cpuidle powernv driver. Cc: Rafael J. Wysocki Cc: Daniel Lezcano Cc: Rob Herring Cc: Lorenzo Pieralisi Cc: linux-pm@vger.kernel.org Cc: Michael Ellerman Cc: Paul Mackerras Cc: linuxppc-dev@lists.ozlabs.org Reviewed-by: Gautham R. Shenoy Signed-off-by: Shreyas B. Prabhu --- Note: Documentation for the device tree bindings is posted here- http://patchwork.ozlabs.org/patch/629125/ Changes in v7 ============= - Using stack instead kzalloc/kcalloc Changes in v5 ============= - Use generic cpuidle constant CPUIDLE_NAME_LEN - Fix return code handling for of_property_read_string_array - Use DT flags to determine if are using stop instruction, instead of cpu_has_feature - Removed uncessary cast with names - &stop_loop -> stop_loop - Added POWERNV_THRESHOLD_LATENCY_NS to filter out idle states with high latency drivers/cpuidle/cpuidle-powernv.c | 61 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index a89f546..d27e955 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -20,6 +20,8 @@ #include #include +#define POWERNV_THRESHOLD_LATENCY_NS 200000 + struct cpuidle_driver powernv_idle_driver = { .name = "powernv_idle", .owner = THIS_MODULE, @@ -27,6 +29,9 @@ struct cpuidle_driver powernv_idle_driver = { static int max_idle_state; static struct cpuidle_state *cpuidle_state_table; + +static u64 stop_psscr_table[CPUIDLE_STATE_MAX]; + static u64 snooze_timeout; static bool snooze_timeout_en; @@ -91,6 +96,17 @@ static int fastsleep_loop(struct cpuidle_device *dev, return index; } #endif + +static int stop_loop(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + ppc64_runlatch_off(); + power9_idle_stop(stop_psscr_table[index]); + ppc64_runlatch_on(); + return index; +} + /* * States for dedicated partition case. */ @@ -169,6 +185,8 @@ static int powernv_add_idle_states(void) u32 latency_ns[CPUIDLE_STATE_MAX]; u32 residency_ns[CPUIDLE_STATE_MAX]; u32 flags[CPUIDLE_STATE_MAX]; + u64 psscr_val[CPUIDLE_STATE_MAX]; + const char *names[CPUIDLE_STATE_MAX]; int i, rc; /* Currently we have snooze statically defined */ @@ -207,11 +225,34 @@ static int powernv_add_idle_states(void) pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n"); goto out; } + if (of_property_read_string_array(power_mgt, + "ibm,cpu-idle-state-names", names, dt_idle_states)) { + pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-names in DT\n"); + goto out; + } + + /* + * If the idle states use stop instruction, probe for psscr values + * which are necessary to specify required stop level. + */ + if (flags[0] & (OPAL_PM_STOP_INST_FAST | OPAL_PM_STOP_INST_DEEP)) + if (of_property_read_u64_array(power_mgt, + "ibm,cpu-idle-state-psscr", psscr_val, dt_idle_states)) { + pr_warn("cpuidle-powernv: missing ibm,cpu-idle-states-psscr in DT\n"); + goto out; + } 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++) { + /* + * If an idle state has exit latency beyond + * POWERNV_THRESHOLD_LATENCY_NS then don't use it + * in cpu-idle. + */ + if (latency_ns[i] > POWERNV_THRESHOLD_LATENCY_NS) + continue; /* * Cpuidle accepts exit_latency and target_residency in us. @@ -224,6 +265,16 @@ static int powernv_add_idle_states(void) powernv_states[nr_idle_states].flags = 0; powernv_states[nr_idle_states].target_residency = 100; powernv_states[nr_idle_states].enter = nap_loop; + } else if ((flags[i] & OPAL_PM_STOP_INST_FAST) && + !(flags[i] & OPAL_PM_TIMEBASE_STOP)) { + strncpy(powernv_states[nr_idle_states].name, + names[i], CPUIDLE_NAME_LEN); + strncpy(powernv_states[nr_idle_states].desc, + names[i], CPUIDLE_NAME_LEN); + powernv_states[nr_idle_states].flags = 0; + + powernv_states[nr_idle_states].enter = stop_loop; + stop_psscr_table[nr_idle_states] = psscr_val[i]; } /* @@ -239,6 +290,16 @@ static int powernv_add_idle_states(void) powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIMER_STOP; powernv_states[nr_idle_states].target_residency = 300000; powernv_states[nr_idle_states].enter = fastsleep_loop; + } else if ((flags[i] & OPAL_PM_STOP_INST_DEEP) && + (flags[i] & OPAL_PM_TIMEBASE_STOP)) { + strncpy(powernv_states[nr_idle_states].name, + names[i], CPUIDLE_NAME_LEN); + strncpy(powernv_states[nr_idle_states].desc, + names[i], CPUIDLE_NAME_LEN); + + powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIMER_STOP; + powernv_states[nr_idle_states].enter = stop_loop; + stop_psscr_table[nr_idle_states] = psscr_val[i]; } #endif powernv_states[nr_idle_states].exit_latency =