From patchwork Wed Feb 7 01:41:15 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Derek Basehore X-Patchwork-Id: 10204433 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 774FD60327 for ; Wed, 7 Feb 2018 01:42:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 46EBD28C5B for ; Wed, 7 Feb 2018 01:42:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3AF2128D58; Wed, 7 Feb 2018 01:42:38 +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 A6F8528C5B for ; Wed, 7 Feb 2018 01:42:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932200AbeBGBmL (ORCPT ); Tue, 6 Feb 2018 20:42:11 -0500 Received: from mail-pl0-f68.google.com ([209.85.160.68]:36517 "EHLO mail-pl0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932226AbeBGBl2 (ORCPT ); Tue, 6 Feb 2018 20:41:28 -0500 Received: by mail-pl0-f68.google.com with SMTP id v3so2481384plg.3 for ; Tue, 06 Feb 2018 17:41:28 -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=hm4Abho1azyMbbiPJonTQHqgEM4RtA3FaYdoOFqdkIw=; b=ntdnqmVQuWG8smp5jOjrUABrW4GXjQ4+PMSlWOhkPQolWN6myVRos0TQTxLgPOyY1p MdSsMuZ9WRF27UKDZK8/xW6EAbRNrtCkgH4fTq0zyGOOPtt6USm8sSpWZEUrmdItnEuu pXn+yCf/dpOChboSt02VPYB7cW2jO6Wz7nD/Y= 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=hm4Abho1azyMbbiPJonTQHqgEM4RtA3FaYdoOFqdkIw=; b=KRp5MhTCUnG1bo2DvLcyBHxvL99YSFlrRtZof4tP+nnrmPWym8pUU3wR1NGjXl0NcB 2i6lqSqjH9w25zui2csyiu9uGpLcLmLW4/L0DMrJTJxfRG1pC+MdiJqUFlpDpe2u/bAK d6WDyJ/YknxPmXPKOI5lmSp6Xpa+S6QfCcr4qhVj2fTPgovTIkyhp+2Yt/5mUyUav356 YyKzesdf4i6nL85IYqGH1jP7URKaffQBf06H8Adgs0VVnH7zcjpdQjS5HE3h7HKjNR+b 0EoTa2X8hbK0f/CmJfY4KMkarOkXRepFSc/4Yod4Cyugs/OTdUaLyp6NhLyW2kuCFtqq T5lA== X-Gm-Message-State: APf1xPC2KRSmA7/Zx1f3eZKlG9eXmYTaQu7boAoVKV6FN7PCcF3jV9ZV KIO0gXn3oHmOd10yG3gQfXRgWg== X-Google-Smtp-Source: AH8x225mlyuFaZ36YjqZfFIqIxcYBUOYrywn7OX/swb0qOCbsra56/PZQEm1VxITMsC5Aw5HN0zxxg== X-Received: by 2002:a17:902:3083:: with SMTP id v3-v6mr4326900plb.426.1517967687872; Tue, 06 Feb 2018 17:41:27 -0800 (PST) Received: from exogeni.mtv.corp.google.com ([2620:0:1000:1600:211e:5908:95bc:4888]) by smtp.gmail.com with ESMTPSA id k71sm573529pfg.52.2018.02.06.17.41.26 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 06 Feb 2018 17:41:27 -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 v5 2/4] irqchip/gic-v3-its: add ability to save/restore ITS state Date: Tue, 6 Feb 2018 17:41:15 -0800 Message-Id: <20180207014117.62611-3-dbasehore@chromium.org> X-Mailer: git-send-email 2.16.0.rc1.238.g530d649a79-goog In-Reply-To: <20180207014117.62611-1-dbasehore@chromium.org> References: <20180207014117.62611-1-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 | 99 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 99 insertions(+) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 06f025fd5726..5e63635e2a7b 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 +3046,96 @@ 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. There's not much we can + * do if this fails. + */ + if (its_force_quiescent(base)) + pr_err("ITS failed to quiesce on resume\n"); + + 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 +3355,9 @@ 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 +3612,7 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists, } } + register_syscore_ops(&its_syscore_ops); + return 0; }