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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5E9CDC001B0 for ; Tue, 8 Aug 2023 11:54:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:CC:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=4IG/jbud+jUfxk3BWrYwruyTglspZdbUY1IdFTvti30=; b=I5leKXSJ+/n68A DAwoP9VY40qpc+PIDo0mWCO4a95Lp7bIjtX6DE2JLz6dKZaxwt04+iFE1EB8Z/g4nAGfUNfloKsyc 2++Yb+agQAgMMy+fgxeFyWQQR1XwOuDxMeMfoY9FZTnbxNs11nAY8M2KiVfiWvDSX8iaaBldiHuwy n2eC3M9BfEkia214DfTCgnFCMtHcZicsZrlNjbqUKkWK/J3XTcYZvgkYsENv19Z2r0Xa3P9Mh+muU Ehms5g+b6i/C1XcebzB8UXZUip/osEN2hpDduXyPZZFm9U8be8gZzr+Yd+Ashs5Srz1LDgW40juei qnvRfFstNap+AkyVGq2A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qTLI4-002WRK-1d; Tue, 08 Aug 2023 11:54:20 +0000 Received: from lelv0142.ext.ti.com ([198.47.23.249]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qTLI1-002WQt-3A for linux-arm-kernel@lists.infradead.org; Tue, 08 Aug 2023 11:54:19 +0000 Received: from lelv0265.itg.ti.com ([10.180.67.224]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id 378Bs6Yf059357; Tue, 8 Aug 2023 06:54:06 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1691495646; bh=85O1LHmFg/AJ8yaKognKgKFx1SZjvS1koBhd4R/gD6w=; h=Date:From:To:CC:Subject:References:In-Reply-To; b=bkSh49bjXjvQxiVC9sI24Tb/WFdJvqVLySYHPdnrPSqsVT/ddYZMMdHpUWtrnQmVj NpLqEufiYT2xQA5YvU0PFkaYSuYeAQKcXDIupDqlRZQUom+GZ8l9ou76UQ55ki0kvL mnIhd3XDxHpFxS7KniEQNYRPjmhCU6/T8LDYxeq8= Received: from DFLE101.ent.ti.com (dfle101.ent.ti.com [10.64.6.22]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 378Bs6IT025553 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 8 Aug 2023 06:54:06 -0500 Received: from DFLE110.ent.ti.com (10.64.6.31) by DFLE101.ent.ti.com (10.64.6.22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Tue, 8 Aug 2023 06:54:04 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DFLE110.ent.ti.com (10.64.6.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Tue, 8 Aug 2023 06:54:04 -0500 Received: from localhost (ileaxei01-snat.itg.ti.com [10.180.69.5]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 378Bs4SH098556; Tue, 8 Aug 2023 06:54:04 -0500 Date: Tue, 8 Aug 2023 17:24:03 +0530 From: Dhruva Gole To: Kevin Hilman CC: Andrew Davis , Nishanth Menon , Tero Kristo , Santosh Shilimkar , , , , Viresh Kumar , "Praneeth Bajjuri" , Tony Lindgren , Dave Gerlach , Vibhore Vardhan , Georgi Vlaev Subject: Re: [PATCH V6 4/4] firmware: ti_sci: Introduce system suspend resume support Message-ID: <20230808115403.dkz6ev5vc6bhcmzh@dhruva> References: <20230803064247.503036-1-d-gole@ti.com> <20230803064247.503036-5-d-gole@ti.com> <3882f0ac-b74c-6eb2-197c-34ca233cd7a3@ti.com> <20230803155541.nwsfwobfkbpefoyw@dhruva> <8c330bd9-5f4e-8cd0-ed02-c3a696d7473a@ti.com> <20230803160815.yfpkdfssv75d4inf@dhruva> <7ho7jifrda.fsf@baylibre.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <7ho7jifrda.fsf@baylibre.com> X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230808_045418_101504_9D806A4A X-CRM114-Status: GOOD ( 46.40 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Kevin, Thanks for the suggestion. I have a rough proposal inline, please can you take a look? I will test those changes and respin this series accordingly On Aug 07, 2023 at 14:57:05 -0700, Kevin Hilman wrote: > Dhruva Gole writes: > > > On Aug 03, 2023 at 11:00:11 -0500, Andrew Davis wrote: > >> On 8/3/23 10:55 AM, Dhruva Gole wrote: > >> > On Aug 03, 2023 at 10:26:32 -0500, Andrew Davis wrote: > >> > > On 8/3/23 1:42 AM, Dhruva Gole wrote: > >> > > > Introduce system suspend resume calls that will allow the ti_sci > >> > > > driver to support deep sleep low power mode when the user space issues a > >> > > > suspend to mem. > >> > > > > >> > > > Also, write a ti_sci_prepare_system_suspend call to be used in the driver > >> > > > suspend handler to allow the system to identify the low power mode being > >> > > > entered and if necessary, send TISCI_MSG_PREPARE_SLEEP with information > >> > > > about the mode is being entered and the address for allocated memory for > >> > > > storing the context during Deep Sleep. > >> > > > > >> > > > We're using "pm_suspend_target_state" to map the kernel's target suspend > >> > > > state to SysFW low power mode. Make sure this is available only when > >> > > > CONFIG_SUSPEND is enabled. > >> > > > > >> > > > Co-developed-by: Dave Gerlach > >> > > > Signed-off-by: Dave Gerlach > >> > > > Signed-off-by: Vibhore Vardhan > >> > > > Signed-off-by: Georgi Vlaev > >> > > > Signed-off-by: Dhruva Gole > >> > > > --- > >> > > > drivers/firmware/ti_sci.c | 63 +++++++++++++++++++++++++++++++++++++++ > >> > > > 1 file changed, 63 insertions(+) > >> > > > > >> > [..snip..] > >> > > > +static int ti_sci_suspend(struct device *dev) > >> > > > +{ > >> > > > + struct ti_sci_info *info = dev_get_drvdata(dev); > >> > > > + int ret; > >> > > > + > >> > > > + ret = ti_sci_cmd_set_io_isolation(&info->handle, TISCI_MSG_VALUE_IO_ENABLE); > >> > > > >> > > After this the will the IOs be in isolation? Or does the firmware wait > >> > > until power down begins later? > >> > > >> > From what I understand, > >> > IOs will be in isolation immediately > >> > > >> > >> That is what I understand too, so then any device that may need to do some > >> external communication for its suspend will not function, this must be the > >> last driver _suspend() the system calls, how do you enforce that? > > > > I will make use of .suspend_noirq callbacks in that case. Does that > > sound better, or is there anything else I may not be aware of? > > Using _noirq just moves the problem. What if other drivers are also > using _noirq callbacks and run after the SCI driver? You still cannot True, this thought occurred to me as well which is why I was thinking that moving it to ATF might be a better choice. > guarantee ordering. > > It seems to me that the IO isolation stuff is a system-wide operation, > and should probably be handled at the platform suspend_ops level > (e.g. suspend_ops->prepare_late()). This would ensure that it runs I must have missed this approach! Are you suggesting something like what was done for am335? static const struct platform_suspend_ops am33xx_pm_ops have a similar code for tisci..? static const struct platform_suspend_ops tisci_pm_ops = { .prepare_late = tisci_set_io_isolation }; And then while resuming we may want the pinctrl driver to scan for the wk_evt bit[0] before the isolation is disabled, so we want the tisci_resume/ remove isolation to be called later than that. So I a wondering if the code below makes sense? static const struct platform_suspend_ops tisci_pm_ops = { .prepare_late = tisci_suspend // also includes set isolation .end = tisci_resume // Disables isolation }; However a minor drawback here maybe that the serial logs on the resume path may not appear when using a serial console for example. However they should be able to easily access using dmesg. > *after* all the driver hooks (even driver _noirq hooks.) and right > before the full suspend (or s2idle.) > > Now, all that being said, I noticed that in v7, you didn't move this to > _noirq, but instead suggested that this be handled by TF-A. I suppose > that's an option also, but my suggestion above should work also. Thanks for the pointer! I do believe it will make more sense to do it from linux itself unless we have no way to do it in linux. > > Kevin [0] Table 5-517. Description Of The Pad Configuration Register Bits https://www.ti.com/lit/pdf/spruid7 NOTE: The hardware works in such a way that as soon as the IO isolation is disabled the wake_evt information is lost so the pinctrl-single driver won't be able to know what pin woke it up if we disable io isolation before it has the chance to look at the padconf registers -- Best regards, Dhruva Gole _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel