From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63959C83F1C for ; Wed, 30 Aug 2023 18:47:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241123AbjH3Sqw convert rfc822-to-8bit (ORCPT ); Wed, 30 Aug 2023 14:46:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343627AbjH3QUz (ORCPT ); Wed, 30 Aug 2023 12:20:55 -0400 Received: from mail-ot1-f46.google.com (mail-ot1-f46.google.com [209.85.210.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6D689D2; Wed, 30 Aug 2023 09:20:53 -0700 (PDT) Received: by mail-ot1-f46.google.com with SMTP id 46e09a7af769-6bc9353be9bso1443483a34.1; Wed, 30 Aug 2023 09:20:53 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693412452; x=1694017252; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=CeS9OdEd68YpyalTdlPZMygmVCYg7KL4ZpDyn/xRe/4=; b=WoekO6vnwNoSIo6QNnKfk2wvZOPC+eVHQ8AoN7YLfbD6na4Go2C/uUXBn6USkCRVUm FrC5WAPq7X/2B5PWgZH4h2LOyUFyYmuHVK+TBDf4ar6ImjHxIpM9BQ+75WGwR87qXzV2 JlZXpY2wLlkHmSMqoMKVnv+sEbUddeu0p+GIZNpzXRpSXkreyGsv1tXl4Hn78vYd9Ssu EUMxyOXCmhH2KQXydpl1prcjnLErzRW+rgsu4EsoaB2TKqmuupJ5Afv1rm0ADu9sl4kD siBtIFnfc+f82Op8BvInsKebB0/B1KafKEVueftMSsxTCZYWU1gmVhke2ye0NJWPDUvE zluQ== X-Gm-Message-State: AOJu0YweeBiGltrcZELXlQPq63TZszfDKv+7vmXTlcJacWY27O6vMDKg hfXHVE4tjsHp870zR75Rzg0Ljaxoy+mUkEAzh+w= X-Google-Smtp-Source: AGHT+IH7TEnfirEhx1gwGguuo2Dzd1et6vj1TBhatbD8UHOw6mPS4F5+8/4Z5y4aVW7DqlbyShcDP4i3A6P7NkHJkKQ= X-Received: by 2002:a4a:de8f:0:b0:573:55af:777c with SMTP id v15-20020a4ade8f000000b0057355af777cmr2802339oou.0.1693412452678; Wed, 30 Aug 2023 09:20:52 -0700 (PDT) MIME-Version: 1.0 References: <20230830161539.3864065-1-quic_poza@quicinc.com> In-Reply-To: <20230830161539.3864065-1-quic_poza@quicinc.com> From: "Rafael J. Wysocki" Date: Wed, 30 Aug 2023 18:20:41 +0200 Message-ID: Subject: Re: [PATCH v4] cpuidle, ACPI: Evaluate LPI arch_flags for broadcast timer To: Oza Pawandeep Cc: sudeep.holla@arm.com, catalin.marinas@arm.com, will@kernel.org, rafael@kernel.org, lenb@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Wed, Aug 30, 2023 at 6:15 PM Oza Pawandeep wrote: > > Arm® Functional Fixed Hardware Specification defines LPI states, > which provide an architectural context loss flags field that can > be used to describe the context that might be lost when an LPI > state is entered. > > - Core context Lost > - General purpose registers. > - Floating point and SIMD registers. > - System registers, include the System register based > - generic timer for the core. > - Debug register in the core power domain. > - PMU registers in the core power domain. > - Trace register in the core power domain. > - Trace context loss > - GICR > - GICD > > Qualcomm's custom CPUs preserves the architectural state, > including keeping the power domain for local timers active. > when core is power gated, the local timers are sufficient to > wake the core up without needing broadcast timer. > > The patch fixes the evaluation of cpuidle arch_flags, and moves only to > broadcast timer if core context lost is defined in ACPI LPI. > > Reviewed-by: Sudeep Holla > Signed-off-by: Oza Pawandeep Acked-by: Rafael J. Wysocki for the ACPI core changes in this patch and I would prefer it to go in via ARM64. > > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > index bd68e1b7f29f..0d455b02971e 100644 > --- a/arch/arm64/include/asm/acpi.h > +++ b/arch/arm64/include/asm/acpi.h > @@ -9,6 +9,7 @@ > #ifndef _ASM_ACPI_H > #define _ASM_ACPI_H > > +#include > #include > #include > #include > @@ -42,6 +43,26 @@ > #define ACPI_MADT_GICC_SPE (offsetof(struct acpi_madt_generic_interrupt, \ > spe_interrupt) + sizeof(u16)) > > +/* > + * Arm® Functional Fixed Hardware Specification Version 1.2. > + * Table 2: Arm Architecture context loss flags > + */ > +#define CPUIDLE_CORE_CTXT BIT(0) /* Core context Lost */ > + > +#ifndef arch_update_idle_state_flags > +static __always_inline void _arch_update_idle_state_flags(u32 arch_flags, > + unsigned int *sflags) > +{ > + if (arch_flags & CPUIDLE_CORE_CTXT) > + *sflags |= CPUIDLE_FLAG_TIMER_STOP; > +} > +#define arch_update_idle_state_flags _arch_update_idle_state_flags > +#endif > + > +#define CPUIDLE_TRACE_CTXT BIT(1) /* Trace context loss */ > +#define CPUIDLE_GICR_CTXT BIT(2) /* GICR */ > +#define CPUIDLE_GICD_CTXT BIT(3) /* GICD */ > + > /* Basic configuration for ACPI */ > #ifdef CONFIG_ACPI > pgprot_t __acpi_get_mem_attribute(phys_addr_t addr); > diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c > index 9718d07cc2a2..420baec3465c 100644 > --- a/drivers/acpi/processor_idle.c > +++ b/drivers/acpi/processor_idle.c > @@ -1221,8 +1221,7 @@ static int acpi_processor_setup_lpi_states(struct acpi_processor *pr) > strscpy(state->desc, lpi->desc, CPUIDLE_DESC_LEN); > state->exit_latency = lpi->wake_latency; > state->target_residency = lpi->min_residency; > - if (lpi->arch_flags) > - state->flags |= CPUIDLE_FLAG_TIMER_STOP; > + arch_update_idle_state_flags(lpi->arch_flags, &state->flags); > if (i != 0 && lpi->entry_method == ACPI_CSTATE_FFH) > state->flags |= CPUIDLE_FLAG_RCU_IDLE; > state->enter = acpi_idle_lpi_enter; > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > index d584f94409e1..c320b474ed56 100644 > --- a/include/linux/acpi.h > +++ b/include/linux/acpi.h > @@ -1471,6 +1471,10 @@ static inline int lpit_read_residency_count_address(u64 *address) > } > #endif > > +#ifndef arch_update_idle_state_flags > +#define arch_update_idle_state_flags(af, sf) do {} while (0) > +#endif > + > #ifdef CONFIG_ACPI_PPTT > int acpi_pptt_cpu_is_thread(unsigned int cpu); > int find_acpi_cpu_topology(unsigned int cpu, int level); > --