From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=2a00:1450:400c:c09::236; helo=mail-wm0-x236.google.com; envelope-from=leif.lindholm@linaro.org; receiver=edk2-devel@lists.01.org Received: from mail-wm0-x236.google.com (mail-wm0-x236.google.com [IPv6:2a00:1450:400c:c09::236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 4FF5221F38822 for ; Thu, 12 Oct 2017 03:21:11 -0700 (PDT) Received: by mail-wm0-x236.google.com with SMTP id u138so11798289wmu.5 for ; Thu, 12 Oct 2017 03:24:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=l9bxmkRMAkj+JBlSJk5sokRG7r3yDGWrSU5qMzlTpAE=; b=gk5Kqu4J55iI+E/f4neapt03WtBrPqCqGEhzTQqmWWP8iwb84jsIbVTy73/O/SfI9H x0xieOm2qGCil7hZyMrMgfuGBIItrxTGkIBZUYk4VmqAacw7I2hwCa0yXqEljapregn2 73nt8PRh0e72CSJHpSQNTqkh9SG03noBc2T5Q= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=l9bxmkRMAkj+JBlSJk5sokRG7r3yDGWrSU5qMzlTpAE=; b=Uo5cQtAH0/NwRSNy8aALK5bxKz+M25VWKaMkga/GyWZFAdkfvXOj/Yvk50HkbkaJRN lEMS2l/dX9YPuTAnTESyzv/n39X9Cet4HXPqjwH3gUU22kaVywuH1WUMY8YDcB5Rc8AT Grfeksgoly1UACWjSMJkzIl5WVYoEcRnbiYBIw08YyQXShDcORtG6zWg/fD4zgTk/Dt1 o3DlH6QPd7Mf89HxMbq4YVzAa1G0NPwNFYyexLk9MPhhSa0nekoXs2FGuJtHnSXRSMXt hWuNgCTkUdw40MqoLVjJ58h6RLASqPPWXHgd8ZJt26BvS8m9NVryJWsg5k/k+dy2qDzO VjAQ== X-Gm-Message-State: AMCzsaXDaKooqu/QNhcYudoVWuqNr21c5nzN30+p8ov9zivh/gjO4jKl Hath0lEmU3/UTaY5YzEP3nQnIQ== X-Google-Smtp-Source: AOwi7QBJuXYx2zPwBxQvzrXAVbDM3mphEg7EpYKjiJ87RppxXXdQ7whrWJ6xRtFI9y0RNoJshdKu2Q== X-Received: by 10.223.128.4 with SMTP id 4mr1883132wrk.9.1507803880347; Thu, 12 Oct 2017 03:24:40 -0700 (PDT) Received: from bivouac.eciton.net (bivouac.eciton.net. [2a00:1098:0:86:1000:23:0:2]) by smtp.gmail.com with ESMTPSA id 50sm24132297wry.84.2017.10.12.03.24.38 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 12 Oct 2017 03:24:38 -0700 (PDT) Date: Thu, 12 Oct 2017 11:24:37 +0100 From: Leif Lindholm To: Marcin Wojtas Cc: Ard Biesheuvel , "edk2-devel@lists.01.org" , Nadav Haklai , Neta Zur Hershkovits , Kostya Porotchkin , Hua Jing , Jan =?utf-8?B?RMSFYnJvxZs=?= Message-ID: <20171012102437.7esnq5tmcrb2ii7x@bivouac.eciton.net> References: <1507736449-6073-1-git-send-email-mw@semihalf.com> <1507736449-6073-2-git-send-email-mw@semihalf.com> <20171011164713.qgkiekieolvjiyk5@bivouac.eciton.net> MIME-Version: 1.0 In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) Subject: Re: [platforms: PATCH 1/8] Marvell/Armada: Implement EFI_RNG_PROTOCOL driver for EIP76 TRNG X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 12 Oct 2017 10:21:12 -0000 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Oct 12, 2017 at 06:39:46AM +0200, Marcin Wojtas wrote: > 2017-10-11 20:15 GMT+02:00 Ard Biesheuvel : > > On 11 October 2017 at 17:47, Leif Lindholm wrote: > >> On Wed, Oct 11, 2017 at 05:40:42PM +0200, Marcin Wojtas wrote: > >>> From: Ard Biesheuvel > >>> + } > >>> + gBS->Stall (10); > >> > >> Why? Why 10? Please add a comment. > >> > >> No other comments on this patch. > >> > > > > I don't remember the details, and I think the 1 ms delay was chosen > > arbitrarily, but the purpose of the delay is to allow the hardware to > > assume the 'ready' state. > > > > I don't have EIP150 docs, but how about a comment: > > // Polling interval for obtaining TRNG data is 10us > gBS->Stall (10); > > I know it's not perfect, but would you accept it?:) Nearly. "Polling interval ... is" sounds a bit too authoritative (unless that is actually what is documented). "Wait for more TRNG data to arrive" would be sufficient. / Leif