From owner-freebsd-current@freebsd.org Tue Feb 4 13:39:50 2020 Return-Path: Delivered-To: freebsd-current@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 5C852246CC5 for ; Tue, 4 Feb 2020 13:39:50 +0000 (UTC) (envelope-from gsnb.gn@gmail.com) Received: from mail-io1-xd29.google.com (mail-io1-xd29.google.com [IPv6:2607:f8b0:4864:20::d29]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 48Bm5d1nlgz3R8M; Tue, 4 Feb 2020 13:39:49 +0000 (UTC) (envelope-from gsnb.gn@gmail.com) Received: by mail-io1-xd29.google.com with SMTP id z193so20925420iof.1; Tue, 04 Feb 2020 05:39:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=PYWqTxtg53eG160lUA6V/PxlbGgEdOVa6oQwxGkOVo8=; b=HE77i9SVbMww83QeIn1ZV0/+Tsl6+2SnBvboQFT2PksCUQn7VkEqu+IyhlZ6hfBiWS 95l6ZFJVbsFhSwWHYgVqrey9tXAK9euh4/heflDvo48FVBjR+seaB7rlmn5AVWCGx5Q8 qZRDxr3SjZDM3Lih9s1FfT7ZYgdVtzhzAi0cK8hSjTikRYjfCvoQeu5Pj0KUGWhvyxPR ou9ivZoyeDg2NgrKh/ZUEpqHydSEhRdYSEmy+XiyL7dZbrXDMe21W4QlQDeAcWuvuhrl yYQuQowsAe/FvHpC7/YJt2OYV3b0YP+tPkalUQsNUO0AgXhPTfFvvRS7Rt/A7U8hOrnq JgZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=PYWqTxtg53eG160lUA6V/PxlbGgEdOVa6oQwxGkOVo8=; b=FbPb9p9KWErJSEsOTNxeyTHhlnlTkakqxnN4MQvlvFy1CgKyDZT98Qi8Z/EhKcZW1K vwyojsLxuM8TUetO8PKB8ddX7E+oXTlOLxjXi6yqUpC4ClEjgTO4CTc0j/A4D+gcgglI NKxNW4CA2a0nPS8V7Y+ESIKp2JKdWCxpSefkeAHi+mNXu7F9MksqI9DiB9575bvGZPYg tG/npx8CnpKhHco9ui+SQ024R4n8JeW8yUz2a17mIE4nFtD0NiDF3HPd8okMSuQBVsON gP0/3FJ1VYrZlHDNHZoi+Y08Q5OcY/uEHtUFUJrEfXuDQt+iQZQlFsGN81d2UqjuMkNg BpIg== X-Gm-Message-State: APjAAAX7DrgJnt2xIGQOx0ZM1H/9USWUQ7mLTIvELRkyCt7PDf09SVTQ E7P89Mt+ZyKh/DEx1iAqE2miekjTdBc2ZuIuOaE/Xlfi X-Google-Smtp-Source: APXvYqzxbOt37RWmZLf0RKBZbNfz3bJJmBGwxBuAkvjBsZMqr+ccDuW6fqGXHNQAMQAkw6GfXmQ8/L7YgAsUaAaVVXs= X-Received: by 2002:a6b:3b4d:: with SMTP id i74mr23611586ioa.146.1580823587444; Tue, 04 Feb 2020 05:39:47 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Niteesh Date: Tue, 4 Feb 2020 19:09:36 +0530 Message-ID: Subject: Re: OFWBUS: How does autoconfiguration work? To: Ian Lepore Cc: "freebsd-current@freebsd.org" X-Rspamd-Queue-Id: 48Bm5d1nlgz3R8M X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=pass header.d=gmail.com header.s=20161025 header.b=HE77i9SV; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (mx1.freebsd.org: domain of gsnbgn@gmail.com designates 2607:f8b0:4864:20::d29 as permitted sender) smtp.mailfrom=gsnbgn@gmail.com X-Spamd-Result: default: False [-2.00 / 15.00]; TO_DN_EQ_ADDR_SOME(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ip6:2607:f8b0:4000::/36]; FREEMAIL_FROM(0.00)[gmail.com]; DKIM_TRACE(0.00)[gmail.com:+]; RCPT_COUNT_TWO(0.00)[2]; DMARC_POLICY_ALLOW(-0.50)[gmail.com,none]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+,1:+,2:~]; SUBJECT_ENDS_QUESTION(1.00)[]; FREEMAIL_ENVFROM(0.00)[gmail.com]; ASN(0.00)[asn:15169, ipnet:2607:f8b0::/32, country:US]; TAGGED_FROM(0.00)[]; DWL_DNSWL_NONE(0.00)[gmail.com.dwl.dnswl.org : 127.0.5.0]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; R_DKIM_ALLOW(-0.20)[gmail.com:s=20161025]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[multipart/alternative,text/plain]; IP_SCORE(0.00)[ip: (-5.39), ipnet: 2607:f8b0::/32(-1.99), asn: 15169(-1.75), country: US(-0.05)]; IP_SCORE_FREEMAIL(0.00)[]; RCVD_IN_DNSWL_NONE(0.00)[9.2.d.0.0.0.0.0.0.0.0.0.0.0.0.0.0.2.0.0.4.6.8.4.0.b.8.f.7.0.6.2.list.dnswl.org : 127.0.5.0]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[] Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Feb 2020 13:39:50 -0000 I am working on an operating systems project at my university, which currently uses lazy driver initialization i.e. that is the drivers initialize the hardware only during the first invocation, for example, the UART hardware is initialized only during the first call to output_char. Currently, we have multiple BSP's to support different variants even though they are quite similar. For example, we have two BSPs to support BeagleBone Black and white. We are trying to avoid this by using device tree files. Our goal is to parse the DTB at boot time and call all the registered drivers to initialize the hardware. By registered drivers, I mean drivers which are statically linked to executable. I am trying to add a system, which will parse the DTB files and initialize them by calling the appropriate drivers. I want a system similar to FreeBSD or Linux a probe and attach method for device drivers. It doesn't have to be as complex as FreeBSD but a simple one will do. If you have any other questions please let me know :) Thanks, Niteesh On Sun, Feb 2, 2020 at 9:07 PM Ian Lepore wrote: > On Sun, 2020-02-02 at 10:02 +0530, Niteesh wrote: > > I couldn't find anything useful for me, I need information about how the > > hardware autoconfiguration works, not autoconf. > > > > Then maybe you need to provide more details about what you're doing, > what you've tried that isn't working, or something. I couldn't make > any sense out of your original question. > > -- Ian > >