From patchwork Thu Feb 8 02:36:46 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Derek Basehore X-Patchwork-Id: 10206515 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 DEFC560327 for ; Thu, 8 Feb 2018 02:37:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D6EBE28681 for ; Thu, 8 Feb 2018 02:37:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CB1AC28707; Thu, 8 Feb 2018 02:37:50 +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=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_HI autolearn=unavailable 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 3FDF528681 for ; Thu, 8 Feb 2018 02:37:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752172AbeBHChf (ORCPT ); Wed, 7 Feb 2018 21:37:35 -0500 Received: from mail-pf0-f196.google.com ([209.85.192.196]:39390 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751706AbeBHCgz (ORCPT ); Wed, 7 Feb 2018 21:36:55 -0500 Received: by mail-pf0-f196.google.com with SMTP id l9so1203023pfi.6 for ; Wed, 07 Feb 2018 18:36:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=s9y5biEv+RFl/1u4Eua0dwSjK+jUzrqU9LcG3m8UF4A=; b=mZ68EZFnbD5SmyshdrNXcNOT7qfiGOFovcRS7hvkvpJAwRBBEB6ZxPhJ3eUL10ogW9 Gnd3ip/vaQUMFMu+wsxnF3bgpZ+3o6laDATTSKTXTmbm5HVSWGUiVi/q0sCEc9yEvWEU V0jqI5b5iRF9FOuA2K6e/UE4dDdJPNFYcIKPg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=s9y5biEv+RFl/1u4Eua0dwSjK+jUzrqU9LcG3m8UF4A=; b=kdFNNa0e/u0zQNaC+Wgt00VSJ9h2YLIqyBQKWcR8jiD4HviGBSxBuHbWmsSfMpcStI qf9NbAJBx+UDwJztpK2PhvsUiJpAT+BO9K5KGVTS85krZwabYa0VGIOk72ELSELRwZaM 4OGbwa4Sn8V1jBHCZXEYVXhrjpfDP0LCgmhz398if5kasILtP/HVVET1stM8BvDXoBZY eSig2Ml2NbIPRjZmM1+pk9RQ2WWSKKISVcOe5DhKfyT76ALfjozYa9a9PrqbI/fPdXam j1BGTmmj/MxzIAfpB5vZWgIeU5aiuYGstKW6YFRCxD2bE/ITEMeJj7d7WszfpIEYJhiv NAfw== X-Gm-Message-State: APf1xPBHHS9cx6NQ3BypCYMd1j89XPhw1xDTM5NhwADnlIAatqNhxFUc DxfFwWVgxYFXXs7WWEOzaG+Cvg== X-Google-Smtp-Source: AH8x226/XakZ0P0zPIhwTrAJ6zdsdSwIE1Mlr5RL3Tw33iCEdZPferebdfGPu3n/QyyZ5laE+Egf1A== X-Received: by 10.99.125.82 with SMTP id m18mr6564299pgn.415.1518057414636; Wed, 07 Feb 2018 18:36:54 -0800 (PST) Received: from exogeni.mtv.corp.google.com ([2620:0:1000:1600:211e:5908:95bc:4888]) by smtp.gmail.com with ESMTPSA id 203sm6901941pfa.110.2018.02.07.18.36.53 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 07 Feb 2018 18:36:53 -0800 (PST) From: Derek Basehore To: linux-kernel@vger.kernel.org Cc: Soby.Mathew@arm.com, sudeep.holla@arm.com, devicetree@vger.kernel.org, robh+dt@kernel.org, mark.rutland@arm.com, linux-pm@vger.kernel.org, rafael.j.wysocki@intel.com, tglx@linutronix.de, briannorris@chromium.org, marc.zyngier@arm.com, Derek Basehore Subject: [PATCH v6 1/3] irqchip/gic-v3-its: add ability to save/restore ITS state Date: Wed, 7 Feb 2018 18:36:46 -0800 Message-Id: <20180208023648.89124-2-dbasehore@chromium.org> X-Mailer: git-send-email 2.16.0.rc1.238.g530d649a79-goog In-Reply-To: <20180208023648.89124-1-dbasehore@chromium.org> References: <20180208023648.89124-1-dbasehore@chromium.org> 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 Some platforms power off GIC logic in suspend, so we need to save/restore state. The distributor and redistributor registers need to be handled in platform code due to access permissions on those registers, but the ITS registers can be restored in the kernel. Signed-off-by: Derek Basehore --- drivers/irqchip/irq-gic-v3-its.c | 103 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 06f025fd5726..35ad48f51dfa 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -46,6 +47,7 @@ #define ITS_FLAGS_CMDQ_NEEDS_FLUSHING (1ULL << 0) #define ITS_FLAGS_WORKAROUND_CAVIUM_22375 (1ULL << 1) #define ITS_FLAGS_WORKAROUND_CAVIUM_23144 (1ULL << 2) +#define ITS_FLAGS_SAVE_SUSPEND_STATE (1ULL << 3) #define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING (1 << 0) @@ -101,6 +103,8 @@ struct its_node { struct its_collection *collections; struct fwnode_handle *fwnode_handle; u64 (*get_msi_base)(struct its_device *its_dev); + u64 cbaser_save; + u32 ctlr_save; struct list_head its_device_list; u64 flags; unsigned long list_nr; @@ -3042,6 +3046,100 @@ static void its_enable_quirks(struct its_node *its) gic_enable_quirks(iidr, its_quirks, its); } +static int its_save_disable(void) +{ + struct its_node *its; + int err = 0; + + spin_lock(&its_lock); + list_for_each_entry(its, &its_nodes, entry) { + void __iomem *base; + + if (!(its->flags & ITS_FLAGS_SAVE_SUSPEND_STATE)) + continue; + + base = its->base; + its->ctlr_save = readl_relaxed(base + GITS_CTLR); + err = its_force_quiescent(base); + if (err) { + pr_err("ITS failed to quiesce\n"); + writel_relaxed(its->ctlr_save, base + GITS_CTLR); + goto err; + } + + its->cbaser_save = gits_read_cbaser(base + GITS_CBASER); + } + +err: + if (err) { + list_for_each_entry_continue_reverse(its, &its_nodes, entry) { + void __iomem *base; + + if (!(its->flags & ITS_FLAGS_SAVE_SUSPEND_STATE)) + continue; + + base = its->base; + writel_relaxed(its->ctlr_save, base + GITS_CTLR); + } + } + spin_unlock(&its_lock); + + return err; +} + +static void its_restore_enable(void) +{ + struct its_node *its; + + spin_lock(&its_lock); + list_for_each_entry(its, &its_nodes, entry) { + void __iomem *base; + int i; + + if (!(its->flags & ITS_FLAGS_SAVE_SUSPEND_STATE)) + continue; + + base = its->base; + + /* + * Make sure that the ITS is disabled. If it fails to quiesce, + * don't restore it since writing to CBASER or BASER + * registers is undefined according to the GIC v3 ITS + * Specification. + */ + if (its_force_quiescent(base)) { + pr_err("ITS(%p): failed to quiesce on resume\n", base); + continue; + } + + gits_write_cbaser(its->cbaser_save, base + GITS_CBASER); + + /* + * Writing CBASER resets CREADR to 0, so make CWRITER and + * cmd_write line up with it. + */ + its->cmd_write = its->cmd_base; + gits_write_cwriter(0, base + GITS_CWRITER); + + /* Restore GITS_BASER from the value cache. */ + for (i = 0; i < GITS_BASER_NR_REGS; i++) { + struct its_baser *baser = &its->tables[i]; + + if (!(baser->val & GITS_BASER_VALID)) + continue; + + its_write_baser(its, baser, baser->val); + } + writel_relaxed(its->ctlr_save, base + GITS_CTLR); + } + spin_unlock(&its_lock); +} + +static struct syscore_ops its_syscore_ops = { + .suspend = its_save_disable, + .resume = its_restore_enable, +}; + static int its_init_domain(struct fwnode_handle *handle, struct its_node *its) { struct irq_domain *inner_domain; @@ -3261,6 +3359,9 @@ static int __init its_probe_one(struct resource *res, ctlr |= GITS_CTLR_ImDe; writel_relaxed(ctlr, its->base + GITS_CTLR); + if (fwnode_property_present(handle, "reset-on-suspend")) + its->flags |= ITS_FLAGS_SAVE_SUSPEND_STATE; + err = its_init_domain(handle, its); if (err) goto out_free_tables; @@ -3515,5 +3616,7 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists, } } + register_syscore_ops(&its_syscore_ops); + return 0; }