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 70D03C433EF for ; Wed, 24 Nov 2021 13:27:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351333AbhKXNav (ORCPT ); Wed, 24 Nov 2021 08:30:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:54120 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350738AbhKXN2d (ORCPT ); Wed, 24 Nov 2021 08:28:33 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id F0C5C6136F; Wed, 24 Nov 2021 12:51:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637758262; bh=IPgjYNRHfrDFg39DqPeCPagU9liyLWJWmv+UmMcbjbg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C3CVThT0c1oO9Qo7/DDjuYOI55ROOULzRWV1eY3+OiWzH56KpvZnxA96GaY8R53EO koPJIaiDpXIp/8IVl6cVuMZkxIpe2wwm3DTnZXZyS3vszoWxo1QLdnvK6vDTuKMNP/ Wq69StqWr41itQpyHOU1FuGfJdZ1B5kZRrRkrur8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tony Lindgren , Sasha Levin Subject: [PATCH 5.10 012/154] bus: ti-sysc: Add quirk handling for reinit on context lost Date: Wed, 24 Nov 2021 12:56:48 +0100 Message-Id: <20211124115702.781588242@linuxfoundation.org> X-Mailer: git-send-email 2.34.0 In-Reply-To: <20211124115702.361983534@linuxfoundation.org> References: <20211124115702.361983534@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tony Lindgren [ Upstream commit 9d881361206ebcf6285c2ec2ef275aff80875347 ] Some interconnect target modules such as otg and gpmc on am335x need a re-init after resume. As we also have PM runtime cases where the context may be lost, let's handle these all with cpu_pm. For the am335x resume path, we already have cpu_pm_resume() call cpu_pm_cluster_exit(). Signed-off-by: Tony Lindgren Signed-off-by: Sasha Levin --- drivers/bus/ti-sysc.c | 108 ++++++++++++++++++++++++-- include/linux/platform_data/ti-sysc.h | 1 + 2 files changed, 103 insertions(+), 6 deletions(-) diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c index 2ff437e5c7051..1622b0f268230 100644 --- a/drivers/bus/ti-sysc.c +++ b/drivers/bus/ti-sysc.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include @@ -52,11 +53,18 @@ struct sysc_address { struct list_head node; }; +struct sysc_module { + struct sysc *ddata; + struct list_head node; +}; + struct sysc_soc_info { unsigned long general_purpose:1; enum sysc_soc soc; - struct mutex list_lock; /* disabled modules list lock */ + struct mutex list_lock; /* disabled and restored modules list lock */ struct list_head disabled_modules; + struct list_head restored_modules; + struct notifier_block nb; }; enum sysc_clocks { @@ -2429,6 +2437,79 @@ static struct dev_pm_domain sysc_child_pm_domain = { } }; +/* Caller needs to take list_lock if ever used outside of cpu_pm */ +static void sysc_reinit_modules(struct sysc_soc_info *soc) +{ + struct sysc_module *module; + struct list_head *pos; + struct sysc *ddata; + int error = 0; + + list_for_each(pos, &sysc_soc->restored_modules) { + module = list_entry(pos, struct sysc_module, node); + ddata = module->ddata; + error = sysc_reinit_module(ddata, ddata->enabled); + } +} + +/** + * sysc_context_notifier - optionally reset and restore module after idle + * @nb: notifier block + * @cmd: unused + * @v: unused + * + * Some interconnect target modules need to be restored, or reset and restored + * on CPU_PM CPU_PM_CLUSTER_EXIT notifier. This is needed at least for am335x + * OTG and GPMC target modules even if the modules are unused. + */ +static int sysc_context_notifier(struct notifier_block *nb, unsigned long cmd, + void *v) +{ + struct sysc_soc_info *soc; + + soc = container_of(nb, struct sysc_soc_info, nb); + + switch (cmd) { + case CPU_CLUSTER_PM_ENTER: + break; + case CPU_CLUSTER_PM_ENTER_FAILED: /* No need to restore context */ + break; + case CPU_CLUSTER_PM_EXIT: + sysc_reinit_modules(soc); + break; + } + + return NOTIFY_OK; +} + +/** + * sysc_add_restored - optionally add reset and restore quirk hanlling + * @ddata: device data + */ +static void sysc_add_restored(struct sysc *ddata) +{ + struct sysc_module *restored_module; + + restored_module = kzalloc(sizeof(*restored_module), GFP_KERNEL); + if (!restored_module) + return; + + restored_module->ddata = ddata; + + mutex_lock(&sysc_soc->list_lock); + + list_add(&restored_module->node, &sysc_soc->restored_modules); + + if (sysc_soc->nb.notifier_call) + goto out_unlock; + + sysc_soc->nb.notifier_call = sysc_context_notifier; + cpu_pm_register_notifier(&sysc_soc->nb); + +out_unlock: + mutex_unlock(&sysc_soc->list_lock); +} + /** * sysc_legacy_idle_quirk - handle children in omap_device compatible way * @ddata: device driver data @@ -2928,12 +3009,14 @@ static int sysc_add_disabled(unsigned long base) } /* - * One time init to detect the booted SoC and disable unavailable features. + * One time init to detect the booted SoC, disable unavailable features + * and initialize list for optional cpu_pm notifier. + * * Note that we initialize static data shared across all ti-sysc instances * so ddata is only used for SoC type. This can be called from module_init * once we no longer need to rely on platform data. */ -static int sysc_init_soc(struct sysc *ddata) +static int sysc_init_static_data(struct sysc *ddata) { const struct soc_device_attribute *match; struct ti_sysc_platform_data *pdata; @@ -2948,6 +3031,7 @@ static int sysc_init_soc(struct sysc *ddata) mutex_init(&sysc_soc->list_lock); INIT_LIST_HEAD(&sysc_soc->disabled_modules); + INIT_LIST_HEAD(&sysc_soc->restored_modules); sysc_soc->general_purpose = true; pdata = dev_get_platdata(ddata->dev); @@ -2994,15 +3078,24 @@ static int sysc_init_soc(struct sysc *ddata) return 0; } -static void sysc_cleanup_soc(void) +static void sysc_cleanup_static_data(void) { + struct sysc_module *restored_module; struct sysc_address *disabled_module; struct list_head *pos, *tmp; if (!sysc_soc) return; + if (sysc_soc->nb.notifier_call) + cpu_pm_unregister_notifier(&sysc_soc->nb); + mutex_lock(&sysc_soc->list_lock); + list_for_each_safe(pos, tmp, &sysc_soc->restored_modules) { + restored_module = list_entry(pos, struct sysc_module, node); + list_del(pos); + kfree(restored_module); + } list_for_each_safe(pos, tmp, &sysc_soc->disabled_modules) { disabled_module = list_entry(pos, struct sysc_address, node); list_del(pos); @@ -3067,7 +3160,7 @@ static int sysc_probe(struct platform_device *pdev) ddata->dev = &pdev->dev; platform_set_drvdata(pdev, ddata); - error = sysc_init_soc(ddata); + error = sysc_init_static_data(ddata); if (error) return error; @@ -3166,6 +3259,9 @@ static int sysc_probe(struct platform_device *pdev) pm_runtime_put(&pdev->dev); } + if (ddata->cfg.quirks & SYSC_QUIRK_REINIT_ON_CTX_LOST) + sysc_add_restored(ddata); + return 0; err: @@ -3248,7 +3344,7 @@ static void __exit sysc_exit(void) { bus_unregister_notifier(&platform_bus_type, &sysc_nb); platform_driver_unregister(&sysc_driver); - sysc_cleanup_soc(); + sysc_cleanup_static_data(); } module_exit(sysc_exit); diff --git a/include/linux/platform_data/ti-sysc.h b/include/linux/platform_data/ti-sysc.h index 9837fb011f2fb..989aa30c598dc 100644 --- a/include/linux/platform_data/ti-sysc.h +++ b/include/linux/platform_data/ti-sysc.h @@ -50,6 +50,7 @@ struct sysc_regbits { s8 emufree_shift; }; +#define SYSC_QUIRK_REINIT_ON_CTX_LOST BIT(28) #define SYSC_QUIRK_REINIT_ON_RESUME BIT(27) #define SYSC_QUIRK_GPMC_DEBUG BIT(26) #define SYSC_MODULE_QUIRK_ENA_RESETDONE BIT(25) -- 2.33.0