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[23.128.96.18]) by mx.google.com with ESMTP id b11si1407998edz.485.2020.12.15.11.57.23; Tue, 15 Dec 2020 11:57:49 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=f+iCtE+T; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727664AbgLOTzK (ORCPT + 99 others); Tue, 15 Dec 2020 14:55:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:47056 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727649AbgLOTzF (ORCPT ); Tue, 15 Dec 2020 14:55:05 -0500 X-Gm-Message-State: AOAM533pqk+EZNgornYxD5KyFdcLeRzJZxCMoaOFzpQJtxMaefHGWUYh J1Fvo51Sok9kLvkRRwcLmbcbS9jh6lObk53pWg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1608062065; bh=18sB+I2TiNDy9kX1hjtB0rhjFr3VDTG6jAxyNvY39wA=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=f+iCtE+TdnFo6Sfq2hOcFR6WJuCtZffDIeT/aHJS015z4K9qcZ5SpL0g1426j/RoB aHrthS2fPlhdv1y6GhmoH3zOIeVYB/2Ak95ZAYO/NFjzIzAKd+wzD5Qm/9ZUzssv5n r2njr1HQUPrJFrVSRK54DjrA/57Ls6NWpaPcj6FppGSeGdpXH2bwNLCsyvoJ/n+yUD c23XdESprqdroaF8EStpY/PraY5GMJbaSIE7XeEQatlJMdB+8NxSiW3KF6aoXPnGQe 0+I7MIqMU49xRj41oR0soA8gCmg0X3o8N66VFV+6zq8C5PTEiPrqfTn3eWhLEwQblY K+k07TcBesjSQ== X-Received: by 2002:a17:906:d784:: with SMTP id pj4mr27585021ejb.360.1608062063367; Tue, 15 Dec 2020 11:54:23 -0800 (PST) MIME-Version: 1.0 References: <20201215155627.2513-1-nsaenzjulienne@suse.de> <20201215184407.GA44849@C02TF0J2HF1T.local> <1e0ad098ca7b1c13dbc6602285b77790b9cd54a1.camel@suse.de> In-Reply-To: <1e0ad098ca7b1c13dbc6602285b77790b9cd54a1.camel@suse.de> From: Rob Herring Date: Tue, 15 Dec 2020 13:54:11 -0600 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 0/6] Expose RPi4'd bootloader configuration To: Nicolas Saenz Julienne Cc: Catalin Marinas , Srinivas Kandagatla , devicetree@vger.kernel.org, "maintainer:BROADCOM BCM7XXX ARM ARCHITECTURE" , "moderated list:BROADCOM BCM2835 ARM ARCHITECTURE" , linux-arm-kernel , "linux-kernel@vger.kernel.org" , Russell King , Will Deacon , Tim Gover , Phil Elwell Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 15, 2020 at 1:01 PM Nicolas Saenz Julienne wrote: > > Hi Catalin, > > On Tue, 2020-12-15 at 18:44 +0000, Catalin Marinas wrote: > > On Tue, Dec 15, 2020 at 04:56:20PM +0100, Nicolas Saenz Julienne wrote: > > > Soon to be released versions of RPi4's firmware will take of care > > > passing their bootloader's configuration to the OS by copying it into > > > memory and creating a reserved memory node in the board's DT. In order > > > to make use of this information, this series introduces a new generic > > > nvmem driver that maps reserved-memory nodes into nvmem devices. > > > > > > An alternative approach, less nice IMO, would be to create a > > > platform-specific 'soc' driver. > > > > What kind of information is this and how would the kernel use it? > > Sorry, I wasn't clear enough, the ultimate goal is to use this information from > user-space, through nvmem's sysfs interface. The kernel itself has no use for > it. That still leaves the first question. Rob