From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E3275326BB for ; Fri, 16 Oct 2026 16:24:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792167844; cv=none; b=t/eRAsodh1GePWChOJa+K2LWZZGS1fBPOtHH0V+8PhaKfJqMldpNhAZHJ9l+BjsnBP0ncJ2NtmmHk9BQ1iIxIss/zJ+6flUPNoz/W3sM4fQB1UKUo139n//3t6NIX39Yha7pWaUUrWj7Jm/Def+/tlTUBODg+OHKe36E1A58Obw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792167844; c=relaxed/simple; bh=klHXWdaX6otqMnaSii+EHKB/5dl9+lLwjTjIXf1+q64=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=H10Pzr9KcAIdlVUso+uZUDFZINMYJ9gjWTwvZvgZTC3+nMMngo2ulJfig1nVljPxj0txdcQBQYndfV3j3slAXIStt/HuIM6LU6oclp06MG0V8sjUpvaV7S2wRGrg/+ppsWlFV1W0Jmf9KC68hkZcROMOFEk/FI+Cyd9shQvbwuY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=DKozTNJE; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=qYj/q64n; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="DKozTNJE"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qYj/q64n" Date: Fri, 16 Oct 2026 18:23:56 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1792167838; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=9qidRa2FBgCR2y0sBJPJyGy5f82k6s8UrQ9M/kGZ7II=; b=DKozTNJEW2AwvZQuAgQg2+mTJJGqe+kkw/MO1d4Yqtn+W9a/xKdX3KFkLlnxMvjL2+pQg8 dbyE11B6RrL1FCd2fRh4+97Ce5LXbqRmzoasHYW1ZD11taY+6lc56+dnqdpvZCHvu58aMK LcdH6V8qt8R9XEBaTR7+jhsH4xa26S/l2heU/8P1OiKbMUsMFmJVj3TBbjBpMU0i45hY+J i62t/yY5DOV9iYt265DWMnjMwGlPVrY0xgLrB6lVpB2w8STHezLO8cFe4y7qQrxvI63BvL 0+G3pQaRkxI2+I5D2BubbY8CohV3UtJbdWjwKtnR6ZsE4h6V4Pa9mGZI02mPOw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1792167838; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=9qidRa2FBgCR2y0sBJPJyGy5f82k6s8UrQ9M/kGZ7II=; b=qYj/q64n/vggtFXpYq0P7zeGT3FC4Vf5ih14OTPFnqEExbJEnVjqq8Ol4VxNbQt+7y26aT 89OYe8ZEwBZ4vgCw== From: Sebastian Andrzej Siewior To: tanmay.shah@amd.com Cc: 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: <20261016162356.m2X9jbCa@linutronix.de> References: <20261015083937.8SDbdK8P@linutronix.de> <1ee3f542-e0b2-41d4-bf6a-b103dabf50cd@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1ee3f542-e0b2-41d4-bf6a-b103dabf50cd@amd.com> On 2026-10-16 11:10:29 [-0500], Shah, Tanmay wrote: > Hello, Hello, > Thank you for your email, please find my response below: Thank you for your email, too. > > 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. And it has to be a per-CPU interrupt? It can't become a regular interrupt which is not per-CPU? Does the driver at some point access per-CPU registers? > Thank you, > Tanmay > Sebastian