From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754132Ab2GEUmk (ORCPT ); Thu, 5 Jul 2012 16:42:40 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:40200 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750720Ab2GEUmi (ORCPT ); Thu, 5 Jul 2012 16:42:38 -0400 Message-ID: <4FF5FC39.3090402@wwwdotorg.org> Date: Thu, 05 Jul 2012 14:42:33 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120615 Thunderbird/13.0.1 MIME-Version: 1.0 To: Marc Dietrich CC: Wei Ni , swarren@nvidia.com, olof@lixom.net, ccross@android.com, linux@arm.linux.org.uk, linux-tegra@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, ldewangan@nvidia.com, arnd@arndb.de, grant.likely@secretlab.ca, cjb@laptop.org Subject: Re: [PATCH 5/5] ARM: tegra: enable wireless in defconfig References: <1341394488-13169-1-git-send-email-wni@nvidia.com> <1341394488-13169-6-git-send-email-wni@nvidia.com> <4FF5F20F.2050005@wwwdotorg.org> <2114579.sqTp7XiW3H@ax5200p> In-Reply-To: <2114579.sqTp7XiW3H@ax5200p> X-Enigmail-Version: 1.4.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/05/2012 02:35 PM, Marc Dietrich wrote: > On Thursday 05 July 2012 13:59:11 Stephen Warren wrote: >> On 07/04/2012 03:34 AM, Wei Ni wrote: >>> New options enabled: >>> * WIRELESS: (dependency) >>> * CFG80211: (dependency) >>> * WLAN: (dependency) >>> * BRCMFMAC: wlan driver, enable as module. >>> >>> diff --git a/arch/arm/configs/tegra_defconfig >>> b/arch/arm/configs/tegra_defconfig >>> >>> +CONFIG_BRCMFMAC=m >> >> Why does this need to be a module? Everything else in tegra_defconfig is >> built-in, and it'd be nice to be consistent here. Built-in makes >> net-booting new kernels from U-Boot much easier, since there aren't any >> modules to copy. > > network drivers (especially wifi) are often modules because they need firmwares. So I certainly see that WiFi modules may need firmware. But I don't see why that should imply they must be modules; they should be able to defer their firmware loading until the firmware is available. > I'm not sure if the kernel can compile them in every case. Our RT2x00 is an > example (which also needs a defconfig entry btw) but brcmfmac also needs it as > modinfo shows. Beside that, I don't think you want to netboot using wifi and u- > boot because this needs a huge wireless framework which u-boot doesn't have. I net-boot using a USB wired Ethernet adapter. The issue isn't that I want to use wireless from U-Boot, but rather than it's easy to download the zImage and .dtb using U-Boot since they're just copied to RAM, but getting a bunch of modules into a filesystem on the target before booting the kernel is more painful.