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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D34FC76186 for ; Mon, 29 Jul 2019 19:42:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4ECEF2054F for ; Mon, 29 Jul 2019 19:42:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564429327; bh=QxH2mou0ZhhzmjsCzvNUYTR3sj0Y2sitMANirnGFbOo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=In4LWWr8vn691E7j74tpCRAbc5PIU6+DwnWrA9D3FYRiZLTJK+WXEDbMLdNWc9207 GOXT4VdjEv66m4b9dWnmxnwtRt3G6JxXPXK/njZQtCz4+1UPKCRmfBBzDeouF9fseZ 1tvCbndffZf61qkt46y/bDjr7f0w6UJ+D3RzNTW8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389270AbfG2TlH (ORCPT ); Mon, 29 Jul 2019 15:41:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:56468 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389242AbfG2TlD (ORCPT ); Mon, 29 Jul 2019 15:41:03 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E89C6217D9; Mon, 29 Jul 2019 19:41:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564429262; bh=QxH2mou0ZhhzmjsCzvNUYTR3sj0Y2sitMANirnGFbOo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cjr9Mk4TD6EGWBS17jC+kdU8EUpzrvGRHrbFpb57Xd33glxVE2pDXgStwZYlt+gcc O2ijOlaM68B3+qpQA7y+KjjQUbLTz2+fyjTFg6BPn/lB8VYmCG47VqPAOkhhdxI7FD xAJ6tkFiEtMXCnFFknjc3I5T/A2fkt96FfUYbQHs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marc Zyngier , Bharat Kumar Gogada , Lorenzo Pieralisi , Sasha Levin Subject: [PATCH 4.19 043/113] PCI: xilinx-nwl: Fix Multi MSI data programming Date: Mon, 29 Jul 2019 21:22:10 +0200 Message-Id: <20190729190705.962255545@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190729190655.455345569@linuxfoundation.org> References: <20190729190655.455345569@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 181fa434d0514e40ebf6e9721f2b72700287b6e2 ] According to the PCI Local Bus specification Revision 3.0, section 6.8.1.3 (Message Control for MSI), endpoints that are Multiple Message Capable as defined by bits [3:1] in the Message Control for MSI can request a number of vectors that is power of two aligned. As specified in section 6.8.1.6 "Message data for MSI", the Multiple Message Enable field (bits [6:4] of the Message Control register) defines the number of low order message data bits the function is permitted to modify to generate its system software allocated vectors. The MSI controller in the Xilinx NWL PCIe controller supports a number of MSI vectors specified through a bitmap and the hwirq number for an MSI, that is the value written in the MSI data TLP is determined by the bitmap allocation. For instance, in a situation where two endpoints sitting on the PCI bus request the following MSI configuration, with the current PCI Xilinx bitmap allocation code (that does not align MSI vector allocation on a power of two boundary): Endpoint #1: Requesting 1 MSI vector - allocated bitmap bits 0 Endpoint #2: Requesting 2 MSI vectors - allocated bitmap bits [1,2] The bitmap value(s) corresponds to the hwirq number that is programmed into the Message Data for MSI field in the endpoint MSI capability and is detected by the root complex to fire the corresponding MSI irqs. The value written in Message Data for MSI field corresponds to the first bit allocated in the bitmap for Multi MSI vectors. The current Xilinx NWL MSI allocation code allows a bitmap allocation that is not a power of two boundaries, so endpoint #2, is allowed to toggle Message Data bit[0] to differentiate between its two vectors (meaning that the MSI data will be respectively 0x0 and 0x1 for the two vectors allocated to endpoint #2). This clearly aliases with the Endpoint #1 vector allocation, resulting in a broken Multi MSI implementation. Update the code to allocate MSI bitmap ranges with a power of two alignment, fixing the bug. Fixes: ab597d35ef11 ("PCI: xilinx-nwl: Add support for Xilinx NWL PCIe Host Controller") Suggested-by: Marc Zyngier Signed-off-by: Bharat Kumar Gogada [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by: Lorenzo Pieralisi Acked-by: Marc Zyngier Signed-off-by: Sasha Levin --- drivers/pci/controller/pcie-xilinx-nwl.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c b/drivers/pci/controller/pcie-xilinx-nwl.c index fb32840ce8e6..4850a1b8eec1 100644 --- a/drivers/pci/controller/pcie-xilinx-nwl.c +++ b/drivers/pci/controller/pcie-xilinx-nwl.c @@ -483,15 +483,13 @@ static int nwl_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, int i; mutex_lock(&msi->lock); - bit = bitmap_find_next_zero_area(msi->bitmap, INT_PCI_MSI_NR, 0, - nr_irqs, 0); - if (bit >= INT_PCI_MSI_NR) { + bit = bitmap_find_free_region(msi->bitmap, INT_PCI_MSI_NR, + get_count_order(nr_irqs)); + if (bit < 0) { mutex_unlock(&msi->lock); return -ENOSPC; } - bitmap_set(msi->bitmap, bit, nr_irqs); - for (i = 0; i < nr_irqs; i++) { irq_domain_set_info(domain, virq + i, bit + i, &nwl_irq_chip, domain->host_data, handle_simple_irq, @@ -509,7 +507,8 @@ static void nwl_irq_domain_free(struct irq_domain *domain, unsigned int virq, struct nwl_msi *msi = &pcie->msi; mutex_lock(&msi->lock); - bitmap_clear(msi->bitmap, data->hwirq, nr_irqs); + bitmap_release_region(msi->bitmap, data->hwirq, + get_count_order(nr_irqs)); mutex_unlock(&msi->lock); } -- 2.20.1