From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=192.198.163.11 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792565924; b=k+RM8rwpgQxsJDIbISDxF9W4AOVw/Qwrglw1ip99aRdcZ6CYHIXWYSyEbBYZvReqqMXK bwIirW0zPH3g9Ae2RPY694wL+stGp93lgHvgjX8eVvD/4Cvhgd4YTd3gCyKV+nRGtVlqJ SaCsMBsTKj9oxVfkxjYxuCx9KlhPaJEdKVCEsUh8RLjPWXPvClqcUfu+49o3M25bBNzby cS3+/CZU5bKhe9oWEv9dK6p0YvhRB+hoLfwhBLnMTvUyVRrsgU3Ri7V5ybOBPbyDmghHO jjtpfbGS4fAu71q1WxS6dFXp+alsVBPHablDecqEYqcF3JZT/49lpnPJw55rfmm7/bg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792565924; h=DMARC-Filter:DKIM-Signature:X-CSE-ConnectionGUID:X-CSE-MsgGUID: X-IronPort-AV:X-IronPort-AV:Received:X-CSE-ConnectionGUID: X-CSE-MsgGUID:X-ExtLoop1:X-IronPort-AV:Received:Date:From:To:Cc: Subject:Message-ID:References:MIME-Version:Content-Type: Content-Disposition:Content-Transfer-Encoding:In-Reply-To: Organization; bh=4CoDiCaTJN+LFxlwyURPQlkHoXPhaz72iTcURzvPQHU=; b=K9mnZPL+jUtG9D4QK60z7W2nbfki5G39IMIYB7vXmCiz7oAh+d1lZQnFji4rFfgsWnR1 085slwN5+pJQgRwn16/Qya8BQWkuhIBii6abh4XrZr3juFi/HbgMP5wMICgsEGLKNfqQ9 lONRVPlCuxCWuRQWkuSQPGsiIP+g3bw6O8N19c/CV4Mux8rSQoioN1Cdfy8/+dbWnAuwz voQc8r5rf2kynjfYW/TY6fuqglYZOcfzIKMgfHJWQtkGj+2cBc2AuMTZRkiykMJYUVm3d PWfHY/MrgM6fpadMMh3/DcfWmgeGy/391+Ag7zoNk7j7DZXShDpYNECAoxnvGm//AmQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=DvSQlGzQ; arc=none smtp.remote-ip=192.198.163.11 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.11]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 473F5606A31A; Wed, 21 Oct 2026 06:58:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 473F5606A31A Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=DvSQlGzQ DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1792565924; x=1824101924; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=i07QuMRn/2JfcFy0JuCMmwxFwETBHdVXa2IAMSqe/48=; b=DvSQlGzQHaF2gS2vowBqFRYEkl0w/Q7LcHEHbOe/+YRD+GZXXq52LB/M 3jiFExm1GHrpTyUHx9BwL+SUNhIxVScaWh6rowgTdphKw9BTF+qc3wV1m OCu0p4lwYCwcueKL0JZVbsdzhAcUiM1TjY27LWoRuJNhnFiaTJjQZSbSL KS5ohGuHGK9kzqnDp/Q9NpfPXbECxehA65apCUWq8yS8crHaSX7XYz9nG EskyxVIdbBm9xY+fbh2UJg3SBGqYbL1fqpHCGyA3tN7nAKqNH30QEfTJ7 XAcHsbctjk6Z+4OO8+MEcBqrqUO6sjD1LAt+whzobf6BagOGFtnGcO3+m w==; X-CSE-ConnectionGUID: +ImzHyDxRfSzdNpaG8LWIw== X-CSE-MsgGUID: oQlBF+K0TE2TXrv22O8YDg== X-IronPort-AV: E=McAfee;i="6800,10657,11941"; a="1184182" X-IronPort-AV: E=Sophos;i="6.27,169,1787036400"; d="scan'208";a="1184182" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by fmvoesa105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Oct 2026 23:58:43 -0700 X-CSE-ConnectionGUID: S6AFesmrT1+KJSlx5aB2uw== X-CSE-MsgGUID: +peAPlOLSZe1ssAQhB/ynQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,169,1787036400"; d="scan'208";a="2933131" Received: from cpetruta-mobl1.ger.corp.intel.com (HELO localhost) ([10.245.245.24]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Oct 2026 23:58:35 -0700 Date: Wed, 21 Oct 2026 09:58:33 +0300 From: Andy Shevchenko To: Lorenzo Pieralisi Cc: "Rafael J. Wysocki (Intel)" , Robin Murphy , Mark Rutland , Marc Zyngier , Daniel Lezcano , Thomas Gleixner , Greg Kroah-Hartman , Danilo Krummrich , Hanjun Guo , Sudeep Holla , Wim Van Sebroeck , Guenter Roeck , Catalin Marinas , Will Deacon , Bartosz Golaszewski , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, driver-core@lists.linux.dev, linux-watchdog@vger.kernel.org Subject: Re: [PATCH RFC 02/11] ACPI: Introduce irq_get() for static fwnodes Message-ID: References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo On Tue, Oct 20, 2026 at 05:30:00PM +0200, Lorenzo Pieralisi wrote: > On Mon, Oct 19, 2026 at 08:05:50PM +0200, Rafael J. Wysocki (Intel) wrote: > > On Mon, Oct 19, 2026 at 12:34 PM Lorenzo Pieralisi > > wrote: [...] > > Basically, yes, the idea is to defer the creation of the platform > > device until the dependency is met. > > > > > till the dependencies are cleared but then, without a _CRS, where will > > > the consumer driver find the platform device resources ? > > > > Well, good question. > > > > > There are multiple facets in this issue and possibly some of them have > > > been already solved but I need to pull them together. > > > > > > > Note that the dependencies can be added to acpi_dep_list after > > > > creating a struct acpi_device with acpi_add_single_object() and > > > > acpi_scan_add_dep() is not really suitable for that, but it should be > > > > doable if the dependencies can be found. > > > > > > > > > I need to have a deeper look into this next week but I wanted to ask first > > > > > whether there was something I missed - most likely. > > > > > > > > Well, it is not really straightforward. > > > > > > Yes it is getting messy. This RFC, with all its flaws, does not transparently > > > prevents enumeration but rather relies on -EPROBE_DEFER to sort out > > > dependencies - though it does so by adding more stuff into ACPI static fwnode > > > that to be honest I'd rather see gone. > > > > I think what you need is a notification mechanism that will trigger > > when a specific device (enumerated via the ACPI Namespace) becomes > > operational. It doesn't look like any of the existing ones (platform > > device probe deferral or ACPI device dependencies tracking) is really > > suitable for your use case. > > Yes. It might just be a notification from ACPI core to say "the driver for > this ACPI device probed, go create platform devices that depends on it". > > We can check and track the dependency in code that does create those > devices today. > > I will think about this to see how bad this might look like. Don't we do something similar in drivers/acpi/x86/lpss.c? > > > > I'm still not sure why you can't represent all devices in the ACPI > > > > namespace in addition to describing some of them in static tables. I > > > > guess that would work for everybody, wouldn't it? > > > > > > That's a fair point - though then code will have to work with firmware > > > that does NOT explicitly require those devices in the namespace (ie: firmware > > > as it is specified _now_); it can turn out to be a mess even less > > > manageable than this discussion ;-) > > > > If it has to work under these conditions anyway, then adding stuff to > > the namespace is rather pointless. > > Yes that's the problem, reworking the code to make it work with namespace > devices is doable the issue is existing firmware and that we can't change it > (and we can't create it in the kernel either). -- With Best Regards, Andy Shevchenko