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 C0454C982E1 for ; Mon, 21 Sep 2026 09:00:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=fMYIHQgx69GNBUVA3OYGBFtoC/ciMIk7Rmfg7wwuKas=; b=zmURB6sQwpg9KS7FtrFx92H9MX DH0243QvzJsQ4EHb2rggk5Cv8MqEpnCyck6k8ZhiHuH226WQxyEzGI7INsnChn3YGp1oH3re3C/Gc o6JnKhQoXm8jJV7sqFbKWM8wG3ID8qPAd7VkLhSGBMaQ5B/bamLLjJYdLxbZTgpAcnzItP5SWu7xQ IH1n7tQQuw8sw1r2GDtXyc7gkVfoQU/FZhEVHGBZ2vYeDFbIodsvVdu20Mbq9AH2VqmkkJmmnJjmP jpgZedHy5IfLf8G0VogwXcH7+aGMoToLBXo+GdoRTnMe5HVUqKSFMqVPbTSugVDpANh9wBA+oaUF5 fbYivlfA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x8Zsy-00000001QSC-2L8f; Mon, 21 Sep 2026 09:00:28 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x8Zsv-00000001QRV-2Zym for linux-arm-kernel@lists.infradead.org; Mon, 21 Sep 2026 09:00:27 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 39BAD1CE0; Mon, 21 Sep 2026 02:00:21 -0700 (PDT) Received: from [10.0.128.141] (unknown [10.0.128.141]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ECAE23F86C; Mon, 21 Sep 2026 02:00:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1789981224; bh=7FAGCstgztp6bQyjfL+K1zBPkIxsy8V7zCgPNPDJtbQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=oSa5BooeCN2HgtM8aUls3mxHMY3MXyU2nS3pbxXQChhKBqdmgK734c/lj7eVm0YO9 ZSKEbPNyh17gcrccayHqVU+68ufFTY1lZApU7H+TSnRhywToCaqGZxCnn+xzsn72jW 7MGPpF9u5Wz+sBuB3BdBclgAlWKwK0iyJ/u15DDo= Message-ID: Date: Mon, 21 Sep 2026 10:00:20 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v18 2/7] firmware: arm_rmm: Check for RMI support at init Content-Language: en-GB To: Jonathan Cameron Cc: kvm@vger.kernel.org, kvmarm@lists.linux.dev, maz@kernel.org, will@kernel.org, catalin.marinas@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, steven.price@arm.com, aneesh.kumar@kernel.org, oupton@kernel.org, gshan@redhat.com, joey.gouly@arm.com, tabba@google.com, yuzenghui@huawei.com, linux-coco@lists.linux.dev, gankulkarni@os.amperecomputing.com, sdonthineni@nvidia.com, alpergun@google.com, fj0570is@fujitsu.com, WeiLin.Chang@arm.com, lpieralisi@kernel.org, enju.kohei@fujitsu.com References: <20260912083611.2513845-1-suzuki.poulose@arm.com> <20260912083611.2513845-3-suzuki.poulose@arm.com> <178978126541.2352296.3637463397103730192.b4-review@b4> From: Suzuki K Poulose In-Reply-To: <178978126541.2352296.3637463397103730192.b4-review@b4> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260921_020025_696691_A0AD95B2 X-CRM114-Status: GOOD ( 17.23 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 19/09/2026 02:27, Jonathan Cameron wrote: >> Query the RMI version number and check if it is a compatible version. >> The first two feature registers are read and exposed for future code to >> use. >> >> We only support this for Little Endian kernels, the Big Endian kernel >> support is anyway marked BROKEN and is being removed. > > Can we have a small comment here on why the default is y > > It's a big thing to opt into by default. Feels like defconfig > material maybe but not in the Kconfig defaults unless I'm missing > something. We need this for KVM arm64. I could drop the default here and KVM selects this anyways. But, how far do we go on this ? Do we need to be able to disable this completely even for KVM ? As such it is a relatively smaller blob: $ size drivers/firmware/arm_rmm/rmi.o text data bss dec hex filename 7477 572 1 8050 1f72 drivers/firmware/arm_rmm/rmi.o Cheers Suzuki > > >> >> Signed-off-by: Steven Price >> Signed-off-by: Suzuki K Poulose > >> diff --git a/drivers/firmware/arm_rmm/Kconfig b/drivers/firmware/arm_rmm/Kconfig >> new file mode 100644 >> index 000000000000..82724ee23186 >> --- /dev/null >> +++ b/drivers/firmware/arm_rmm/Kconfig >> @@ -0,0 +1,26 @@ >> + >> +config ARCH_SUPPORTS_RMM >> + bool >> + >> +config ARM_RMM_RMI >> + bool "Realm Management Interface (RMI) Support" >> + depends on ARCH_SUPPORTS_RMM >> + default y > Really? Why? >