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 7F950CCF2DA for ; Mon, 19 Oct 2026 10:06:36 +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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=PcNOXqyNxVuYWyzbp1QnwdLMw35li5hGmPS33Nttnsw=; b=t7DUTKsbILZToEcowIcjzzRCZe dkP7nF7dQDS91zC5XhtHtgDY910V+OVPHkq8A+LSzipeeUMn8nBbzaecKCD+fVbGE3GAgRFqbRhNn PPIpaXmEb2DHv3KiNfy/c6K5rp1/tJXCiP9HWawzcLA8lfaMvl9FpF2dIQrxJYW3ZWGWzzuEcR0GN R+GoYaQRBAYahhOgxFaMhxyLX4VkMskaciOSuvxv31EwdNw69CrExzxmLyDQ54GC5Y7sdyp5cf9Vx 33vKyhTEynEypJ1j7uWnYRjM7sg1yIKeKBJejtyq+gUGwcYffJK7BKrayiBQhyo4gJBfQl56vAmjw 16aiFZyg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xIkGD-000000076k8-07gX; Mon, 19 Oct 2026 10:06:29 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xIkGB-000000076i0-0cIK for linux-arm-kernel@lists.infradead.org; Mon, 19 Oct 2026 10:06:27 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 81EC940F20; Mon, 19 Oct 2026 10:06:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D9A671F000C4; Mon, 19 Oct 2026 10:06:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792404386; bh=PcNOXqyNxVuYWyzbp1QnwdLMw35li5hGmPS33Nttnsw=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=W8hOKmbqIRQafhh1GRUUbkc8AnOdIEHvEXad95z150YDdAx7vJrxtQR0G6MDqHPPL nz0Dv/E7S3lutezkPlC0i5Rc4jJAVxIAjLHYf8hTQCDbzWviQHVUd4/J6jf5OAp9fN qVj12uRa5bQRUwICfBZjapIH4QOJvc2YMUCoo4tC9X7kKyQmuoAQqCJcyOXO5WfHaS p3B+xT9bA4CExjZ1tgXqieQGovgQXtSjT/bvCR3tiGV91lA3GMdRkperq6ho5MDMaz fpqP1CSmQvuZDXkrvCV9EFxLYZhlUz991fUtIGL3nw28W4bwkx5HZXdNtCZZgG4mnH 1/kZ4j52r+tOg== Date: Mon, 19 Oct 2026 11:06:22 +0100 From: Sudeep Holla To: tanmay.shah@amd.com Cc: Sebastian Andrzej Siewior , Sudeep Holla , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Jassi Brar , Michal Simek , Harini T , Saeed Nowshadi Subject: Re: [Q] zynqmp-ipi-mailbox and SGI interrupts Message-ID: <20261019-innocent-opalescent-urchin-7feffa@sudeepholla> References: <20261015083937.8SDbdK8P@linutronix.de> <1ee3f542-e0b2-41d4-bf6a-b103dabf50cd@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1ee3f542-e0b2-41d4-bf6a-b103dabf50cd@amd.com> 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 Fri, Oct 16, 2026 at 11:10:29AM -0500, Shah, Tanmay wrote: > Hello, > > Thank you for your email, please find my response below: > > On 10/15/2026 3:39 AM, Sebastian Andrzej Siewior wrote: > > Hi, > > > > The ZynqMP IPI Mailbox driver supports two bindings of which > > xlnx,versal-ipi-mailbox is not present in any kernel dts file and > > This new bindings are for Versal and later SoCs which has buffer-less > IPI. It supports only notification to the other core without any data > transfer. The device-tree nodes may not be available in the upstream > kernel yet, but it is used by other consumers. Here is an example: > > https://github.com/Xilinx/u-boot-xlnx/blob/master/arch/arm/dts/versal-net-vn-x-b2197-01-revA.dts#L100 > > > > xlnx,zynqmp-ipi-mailbox is used in two .dtsi files. > > For the per-CPU interrupts the irq-type should be 2 (which would > > correspond with GIC_ESPI in the dts, no?) which I can't find. > > Before the IPI_IRQ_TYPE_SGI it used to check for the value less than 16 > > I also can't find this in the two available dts file. > > I did browse over the "AMD Versal Virt" but it also looks not present. > > > > My question is whether this is used or just a development step that > > never got somewhere. > > No, it is the actual use case supported by the driver. Just the > device-tree node is not in the upstream kernel, because it is usually > project/vendor/consumer specific. > > > My guess is that the device tree here is preconfigured from the boot > > firmware. > > Yes. > > > So is this SGI-IPI a thing or not? > > > > Yes it is. Ideally, TF-A and Linux can share the IPI. If the IPI > interrupt is used by the TF-A and the expectation is that Linux mailbox > work on the same IPI (because all other IPIs are busy) then the work > around is, TF-A will generate SGI for the linux mbox driver, and the > mbox driver will use that SGI via device-tree. > > It is a vendor specific use case. So the dt-node for this use case, may > not be available in the usptream kernel, but can be enabled if correct > SGI is configured via the device-tree. > Any solution to support SGIs in GIC properly needs to be generic and don't add any vendor specific solution. I proposed a solution for FF-A a while ago, please check if that works for your platform as well[1] -- Regards, Sudeep [1] https://lore.kernel.org/all/20260412-b4-ffa_ns_sgi_gicv3-v1-0-af61243eb405@kernel.org/