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 8668DC6FD1F for ; Tue, 26 Mar 2024 15:37:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Rl1C/m4Tsk4kwrZsYHWMG/U2NHUpYQIhI2a3UbAiKs4=; b=TrUZDNGRWbsewB 6X41muwKXHmVyQd3F4vnnvYP3jy8m42PpxtTRGRDsjWW3EQwhKPslTdwbgmQr92fqJqi4PyuDOXwq f89b1j9pr6nN0PfKRc2ZfZUNQa8uO0wc8gxuf0yE4r1A6tNR+/miaEZlzZnnYRQuAPVcROGfQk39M fhoORe7ur8ISYIrexKTj8X6eQlM3ojDYRJnIAJQYog5JB7diT3go0s6QifecUseOObKf8H7L9d5Xk 8uYGQ1+uZmES7qSYwZp4p/YlUNxL61zEwZYVkGdw0RFw1wDGzjjNgGNJsnmErfLapreEnqGbQr/nN G4pJ7mhLFrQSUA+SGvgA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rp8rh-00000005Dq3-1avv; Tue, 26 Mar 2024 15:37:29 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rp8pr-00000005CvN-3wxQ for linux-arm-kernel@lists.infradead.org; Tue, 26 Mar 2024 15:35:42 +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 86D252F4; Tue, 26 Mar 2024 08:36:08 -0700 (PDT) Received: from bogus (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CFC993F694; Tue, 26 Mar 2024 08:35:33 -0700 (PDT) Date: Tue, 26 Mar 2024 15:35:31 +0000 From: Sudeep Holla To: Jens Wiklander Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Marc Bonnici , Sudeep Holla , Olivier Deprez , Lorenzo Pieralisi , Bertrand Marquis Subject: Re: [PATCH v2] firmware: arm_ffa: support running as a guest in a vm Message-ID: References: <20240325081335.2326979-1-jens.wiklander@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20240325081335.2326979-1-jens.wiklander@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240326_083536_308203_A578A23E X-CRM114-Status: GOOD ( 16.71 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Mar 25, 2024 at 09:13:35AM +0100, Jens Wiklander wrote: > Add support for running the driver in a guest to a hypervisor. The main > difference is introducing notification pending interrupt and that > FFA_NOTIFICATION_BITMAP_CREATE doesn't need to be called. > > The guest may need to use a notification pending interrupt instead of or > in addition to the schedule receiver interrupt. The above statement makes me worry a bit that we are still not on the same page about NPI vs SRI. NPI need not exist in addition to SRI. And in v1 you did mention you have SRI in the guest as well. Then why do we need NPI in addition to that. As part of SRI, the callback ffa_self_notif_handle gets registered and will be called as part of SRI handling. What you do in notif_pend_irq_handler(), exactly what ffa_self_notif_handle() already does. I am still struggling to understand the usecase here. If you just have NPI and no SRI when running the driver in the VM, then it aligns with my understanding of possible use-case(not the one you mentioned in v1: where FF-A driver in VM will have SRI as OPTEE is the secondary scheduler) If we are supporting NPI or SRI, I think we can see if we can further simplify this change, but I want to get to an agreement with usage model before we dig into implementation details in this patch. -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel