Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752993AbbKMF4M (ORCPT ); Fri, 13 Nov 2015 00:56:12 -0500 Received: from mail-yk0-f176.google.com ([209.85.160.176]:33262 "EHLO mail-yk0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751651AbbKMF4J (ORCPT ); Fri, 13 Nov 2015 00:56:09 -0500 MIME-Version: 1.0 In-Reply-To: <1445967656-28292-3-git-send-email-mtitinger+renesas@baylibre.com> References: <20151019205825.GA82426@linaro.org> <1445967656-28292-1-git-send-email-mtitinger+renesas@baylibre.com> <1445967656-28292-3-git-send-email-mtitinger+renesas@baylibre.com> Date: Fri, 13 Nov 2015 13:56:08 +0800 Message-ID: Subject: Re: [RFC v3 2/7] PM / Domains: support idle-states as genpd multiple-state. From: Zhaoyang Huang To: Marc Titinger Cc: Lina Iyer , rjw@rjwysocki.net, khilman@kernel.org, Axel Haslam , Benoit Cousson , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Marc Titinger Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 11615 Lines: 271 On 28 October 2015 at 01:40, Marc Titinger wrote: > From: Marc Titinger > > This patch allows cluster-level idle-states to being soaked in as generic > domain power states, in order for the domain governor to chose the most > efficient power state compatible with the device constraints. Similarly, > devices can register power-states into the cluster domain, in a manner > consistent with idle-states. > > This is a attempt to address device-retention states for devices that > are not hooked to runtime-pm, but feature a retention state handled by > the same firmware that handles idle-states. For instance a L2 caches. > > With Juno, in this example the idle-state 'cluster-sleep-0 ' is known from > each cluster generic domain, as the deepest sate. > > cat /sys/kernel/debug/pm_genpd/* > > Domain State name Enter (ns) / Exit (ns) > ------------------------------------------------------------- > a53_pd cluster-sleep-0 1500000 / 800000 > a57_pd cluster-sleep-0 1500000 / 800000 > > domain status pstate slaves > /device runtime status > ----------------------------------------------------------------------- > a53_pd on > /devices/system/cpu/cpu0 active > /devices/system/cpu/cpu3 suspended > /devices/system/cpu/cpu4 suspended > /devices/system/cpu/cpu5 suspended > /devices/platform/D1 suspended > a57_pd cluster-sleep-0 > /devices/system/cpu/cpu1 suspended > /devices/system/cpu/cpu2 suspended > > Signed-off-by: Marc Titinger > --- > .../devicetree/bindings/power/power_domain.txt | 29 ++++++ > drivers/base/power/domain.c | 102 ++++++++++++++++++++- > include/linux/pm_domain.h | 3 + > 3 files changed, 131 insertions(+), 3 deletions(-) > > diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt > index 025b5e7..2657e19 100644 > --- a/Documentation/devicetree/bindings/power/power_domain.txt > +++ b/Documentation/devicetree/bindings/power/power_domain.txt > @@ -29,6 +29,16 @@ Optional properties: > specified by this binding. More details about power domain specifier are > available in the next section. > > + - cpu-idle-states : a phandle of an idle-state that shall be soaked into a > + generic domain power state. > + CPU domains: Deep c-states that match a cluster power-off can be delegated to the > + generic power domain. Device other than CPUs may have register intermediate > + power states in the same domain. The domain governor can do a good job in > + electing a power state when the last cpu is powered off as devices in the > + same genpd may register intermediate states. > + Devices : a device may register an intermediate c-state matching a memory > + retention feature for instance. > + > Example: > > power: power-controller@12340000 { > @@ -55,6 +65,25 @@ Example 2: > #power-domain-cells = <1>; > }; > > +Example 3: > + > + pm-domains { > + a57_pd: a57_pd@ { > + /* will have a57 platform ARM_PD_METHOD_OF_DECLARE*/ > + compatible = "arm,pd","arm,cortex-a57"; > + #power-domain-cells = <0>; > + cpu-idle-states = <&CLUSTER_SLEEP_0>; Should the "cpu_idle_states" be "domain-idle-states", which is consistent to the following code. > + }; > + > + a53_pd: a53_pd@ { > + /* will have a a53 platform ARM_PD_METHOD_OF_DECLARE*/ > + compatible = "arm,pd","arm,cortex-a53"; > + #power-domain-cells = <0>; > + cpu-idle-states = <&CLUSTER_SLEEP_0>; > + }; > + }; > + > + > The nodes above define two power controllers: 'parent' and 'child'. > Domains created by the 'child' power controller are subdomains of '0' power > domain provided by the 'parent' power controller. > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c > index 6b2d771..8512e28 100644 > --- a/drivers/base/power/domain.c > +++ b/drivers/base/power/domain.c > @@ -1345,7 +1345,8 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, > else { > dev_pm_qos_add_notifier(dev, &gpd_data->nb); > atomic_inc(&genpd->usage_count); > - printk("Add device %d\n", atomic_read(&genpd->usage_count)); > + dev_info(dev, "Add device %d\n", > + atomic_read(&genpd->usage_count)); > } > return ret; > } > @@ -1592,7 +1593,7 @@ static int state_cmp(const void *a, const void *b) > int pm_genpd_insert_state(struct generic_pm_domain *genpd, > const struct genpd_power_state *state) > { > - int ret = 0; > + int i, ret = 0; > int state_count = genpd->state_count; > > if (IS_ERR_OR_NULL(genpd) || (!state)) > @@ -1601,11 +1602,18 @@ int pm_genpd_insert_state(struct generic_pm_domain *genpd, > if (state_count >= GENPD_POWER_STATES_MAX) > ret = -ENOMEM; > > + /* Bail out, this state was already registered.*/ > + for (i = 0; i < state_count; i++) > + if (!strncmp(state->name, genpd->states[i].name, > + GENPD_MAX_NAME_SIZE)) > + return 0; > + > #ifdef CONFIG_PM_ADVANCED_DEBUG > /* to save memory, Name allocation will happen if debug is enabled */ > genpd->states[state_count].name = kstrndup(state->name, > GENPD_MAX_NAME_SIZE, > GFP_KERNEL); > + > if (!genpd->states[state_count].name) { > pr_err("%s Failed to allocate state '%s' name.\n", > genpd->name, state->name); > @@ -1963,6 +1971,93 @@ static void genpd_dev_pm_sync(struct device *dev) > genpd_queue_power_off_work(pd); > } > > + > +static int dt_cpuidle_to_genpd_power_state(struct genpd_power_state > + *genpd_state, > + struct device_node *state_node) > +{ > + int err = 0; > + u32 latency; > + > + err = of_property_read_u32(state_node, "wakeup-latency-us", &latency); > + if (err) { > + u32 entry_latency, exit_latency; > + > + err = of_property_read_u32(state_node, "entry-latency-us", > + &entry_latency); > + if (err) { > + pr_debug(" * %s missing entry-latency-us property\n", > + state_node->full_name); > + return -EINVAL; > + } > + > + err = of_property_read_u32(state_node, "exit-latency-us", > + &exit_latency); > + if (err) { > + pr_debug(" * %s missing exit-latency-us property\n", > + state_node->full_name); > + return -EINVAL; > + } > + /* > + * If wakeup-latency-us is missing, default to entry+exit > + * latencies as defined in idle states bindings > + */ > + latency = entry_latency + exit_latency; > + } > + > + genpd_state->power_on_latency_ns = 1000 * latency; > + > + err = of_property_read_u32(state_node, "entry-latency-us", &latency); > + if (err) { > + pr_debug(" * %s missing min-residency-us property\n", > + state_node->full_name); > + return -EINVAL; > + } > + > + genpd_state->power_off_latency_ns = 1000 * latency; > + > + return 0; > +} > + > +int of_genpd_device_parse_states(struct device_node *np, > + struct generic_pm_domain *genpd) > +{ > + struct device_node *state_node; > + int i, err = 0; > + > + for (i = 0;; i++) { > + struct genpd_power_state genpd_state; > + > + state_node = of_parse_phandle(np, "domain-idle-states", i); > + if (!state_node) > + break; > + > + err = dt_cpuidle_to_genpd_power_state(&genpd_state, > + state_node); > + if (err) { > + pr_err > + ("Parsing idle state node %s failed with err %d\n", > + state_node->full_name, err); > + err = -EINVAL; > + break; > + } > +#ifdef CONFIG_PM_ADVANCED_DEBUG > + genpd_state.name = kstrndup(state_node->name, > + GENPD_MAX_NAME_SIZE, GFP_KERNEL); > + if (!genpd_state.name) > + err = -ENOMEM; > +#endif > + of_node_put(state_node); > + err = pm_genpd_insert_state(genpd, &genpd_state); > + if (err) > + break; > +#ifdef CONFIG_PM_ADVANCED_DEBUG > + kfree(genpd_state.name); > +#endif > + } > + return err; > +} > + > /** > * genpd_dev_pm_attach - Attach a device to its PM domain using DT. > * @dev: Device to attach. > @@ -1996,7 +2091,6 @@ int genpd_dev_pm_attach(struct device *dev) > if (ret < 0) { > if (ret != -ENOENT) > return ret; > - > /* > * Try legacy Samsung-specific bindings > * (for backwards compatibility of DT ABI) > @@ -2034,6 +2128,8 @@ int genpd_dev_pm_attach(struct device *dev) > goto out; > } > > + of_genpd_device_parse_states(pd_args.np, pd); > + > dev->pm_domain->detach = genpd_dev_pm_detach; > dev->pm_domain->sync = genpd_dev_pm_sync; > ret = genpd_poweron(pd); > diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h > index 24621be..48ab3b1 100644 > --- a/include/linux/pm_domain.h > +++ b/include/linux/pm_domain.h > @@ -248,6 +248,9 @@ struct generic_pm_domain *__of_genpd_xlate_onecell( > struct of_phandle_args *genpdspec, > void *data); > > +int of_genpd_device_parse_states(struct device_node *np, > + struct generic_pm_domain *genpd); > + > int genpd_dev_pm_attach(struct device *dev); > #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ > static inline int __of_genpd_add_provider(struct device_node *np, > -- > 1.9.1 > > -- > 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/