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 0F87FC433EF for ; Thu, 21 Jul 2022 07:04:46 +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=1etKUQVNyV35Jjyob16NzrIghjkVxHY320v4aKNJe1Y=; b=Wh3h0aVYIX0PJN 9zit/boTQIEo+qqhc9ycy5fryU+e5f9wFcGslB94mdKYzoqrhX3gfvQkK5G+R4O9QHUco4xlR3Q51 2wmF9RYzU1rxniLJ7VdJMHje+eyRfp6Xbemv4V1V+zkBittZxB7iVyOnAy/KrVs4SPOWZl5brayWj F9JRywpCs8NQJzgYjFoOpEvbtHa2RXqjYnDz66D9nyQWUoy2cYtg3JvBBA4nspNGh6qQeqV1axYkp un8qkyBA6hwShJdB0A8QAhmkfvYklG2pqMP/uAjnWXWqca4l7Q2h+KRfYb4czqLnVqONOytKs89E/ Ez3KjmdhXMDiDcWz9t6g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oEQDk-001QPe-9S; Thu, 21 Jul 2022 07:03:40 +0000 Received: from mga12.intel.com ([192.55.52.136]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oEQDg-001QOX-Pq for linux-arm-kernel@lists.infradead.org; Thu, 21 Jul 2022 07:03:38 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1658387016; x=1689923016; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=tVVixsePGuWthpIXG239h4qnAJPBy+VTisKlJiPtTCs=; b=UaIIoFoBLHLu/zTFqbGEn7HswXHNfoXMvFtTiecFzCqM6VFgrD4EDDgD OlXH5eT93ICu4c5CXwROgZmNtCVdQ4TM6DodHqJ0XM1I0OYNdanfw2zcf wlTbji2qGMYqHox1YGOzaxZ4vvDscQIJUZyjNxsT8zznJ3o84q4Oe2kuj KW16QSPUGcvsnipAi8yaC5jUJuRFiLdP8RbrXkVX+amdTW1rhs6b5oTBi HKL8h/CCmIOko9Q5L22IPAR9quYswH9jjSFURUQJJCb5s1/lMdOL0Lr7g lEXr8+AY1SZwEErF6XVz/6Mr1dT8rTqTtjXK2zDCyPYPKJ37S9sJipoMu Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10414"; a="266746397" X-IronPort-AV: E=Sophos;i="5.92,288,1650956400"; d="scan'208";a="266746397" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Jul 2022 00:03:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.92,288,1650956400"; d="scan'208";a="573621422" Received: from yilunxu-optiplex-7050.sh.intel.com (HELO localhost) ([10.239.159.165]) by orsmga006.jf.intel.com with ESMTP; 21 Jul 2022 00:03:32 -0700 Date: Thu, 21 Jul 2022 14:54:54 +0800 From: Xu Yilun To: "Manne, Nava kishore" Cc: Nava kishore Manne , "mdf@kernel.org" , "hao.wu@intel.com" , "trix@redhat.com" , "robh+dt@kernel.org" , "krzysztof.kozlowski+dt@linaro.org" , "michal.simek@xilinx.com" , "linux-fpga@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "git@xilinx.com" , Rob Herring Subject: Re: [PATCH v2 2/3] fpga: region: Add fpga-region 'power-domains' property Message-ID: <20220721065454.GA1689481@yilunxu-OptiPlex-7050> References: <20220523134517.4056873-1-nava.manne@xilinx.com> <20220523134517.4056873-3-nava.manne@xilinx.com> <20220624162815.GA2142910@yilunxu-OptiPlex-7050> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220721_000336_919886_0C1A6F99 X-CRM114-Status: GOOD ( 38.97 ) 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 On Mon, Jul 18, 2022 at 06:46:32AM +0000, Manne, Nava kishore wrote: > Hi Yilun, > > Please find my response inline. > > > -----Original Message----- > > From: Xu Yilun > > Sent: Friday, June 24, 2022 9:58 PM > > To: Nava kishore Manne > > Cc: mdf@kernel.org; hao.wu@intel.com; trix@redhat.com; > > robh+dt@kernel.org; krzysztof.kozlowski+dt@linaro.org; > > michal.simek@xilinx.com; linux-fpga@vger.kernel.org; > > devicetree@vger.kernel.org; linux-kernel@vger.kernel.org; linux-arm- > > kernel@lists.infradead.org; git@xilinx.com; Rob Herring > > Subject: Re: [PATCH v2 2/3] fpga: region: Add fpga-region 'power-domains' > > property > > > > CAUTION: This message has originated from an External Source. Please use > > proper judgment and caution when opening attachments, clicking links, or > > responding to this email. > > > > > > On Mon, May 23, 2022 at 07:15:16PM +0530, Nava kishore Manne wrote: > > > Add fpga-region 'power-domains' property to allow to handle the > > > FPGA/PL power domains. > > > > > > Signed-off-by: Nava kishore Manne > > > Acked-by: Rob Herring > > > --- > > > Changes for v2: > > > - Updated power-domains description. > > > > > > .../devicetree/bindings/fpga/fpga-region.txt | 14 ++++++++++++++ > > > 1 file changed, 14 insertions(+) > > > > > > diff --git a/Documentation/devicetree/bindings/fpga/fpga-region.txt > > > b/Documentation/devicetree/bindings/fpga/fpga-region.txt > > > index 7d3515264838..f299c3749505 100644 > > > --- a/Documentation/devicetree/bindings/fpga/fpga-region.txt > > > +++ b/Documentation/devicetree/bindings/fpga/fpga-region.txt > > > @@ -196,6 +196,20 @@ Optional properties: > > > - config-complete-timeout-us : The maximum time in microseconds time > > for the > > > FPGA to go to operating mode after the region has been programmed. > > > - child nodes : devices in the FPGA after programming. > > > +- power-domains : A phandle and power domain specifier pair to the > > power domain > > > + which is responsible for turning on/off the power to the FPGA/PL > > region. > > > > Could you help explain what is PL? > > > > > +Example: > > > + fpga_full: fpga-full { > > > + compatible = "fpga-region"; > > > + fpga-mgr = <&zynqmp_pcap>; > > > + #address-cells = <2>; > > > + #size-cells = <2>; > > > + ranges; > > > + power-domains = <&zynqmp_firmware PL_PD>; > > > + }; > > > + > > > + The PL_PD power domain will be turned on before loading the > > > +bitstream and turned off while removing/unloading the bitstream using > > overlays. > > > > I think the single power-domain may not cover some use cases that of-fpga- > > region driver supports. > > I am not sure which use case you are talking about. Can you please point me the exact use case here? > > > It is possible there are already devices in fpga-region > > for static OF tree, or an overlay with no 'firmware-name' but 'external-fpga- > > config'. In these cases power domains may still be needed, is it? > > > > It's an optional property user can decide whether he needs this support or not for 'external-fpga-config > Use case. If an external-fpga-config FPGA region needs to enable a power domain before sub devices population, how could it config the DT? I assume in this patch "power-domains" property is only used before & after reconfiguration but external-fpga-config FPGA region may need no reconfiguration. > > > Another case is the fpga-region may need multiple power domains? > > > > In our use case full region and relevant partial regions have different power domains and > this patch is capable of handle different power domain regions (full and partial regions) If a FPGA region needs 2 or more power domains for partial reconfiguration, how could we find out and enable them all? >From the 2 cases, I see as a generic driver, there may be need to enable different power domains at different moments. And I'm afraid a simple implementation of pm_runtime_get before reconfiguration may limit the usage of "power-domains" property for of-fpga-region. Thanks, Yilun > > > Since the of-fpga-region driver is a generic fpga-region driver, we may > > investigate more for a compatible power-domain solution. > > > > Please share your thoughts here we will try to align with it. > > Regards, > Navakishore. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel