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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50C22C433EF for ; Mon, 15 Nov 2021 17:39:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F90B632E6 for ; Mon, 15 Nov 2021 17:39:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237956AbhKORl5 (ORCPT ); Mon, 15 Nov 2021 12:41:57 -0500 Received: from mail.kernel.org ([198.145.29.99]:51568 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237314AbhKORTY (ORCPT ); Mon, 15 Nov 2021 12:19:24 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1CC7C61C12; Mon, 15 Nov 2021 17:14:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1636996443; bh=klj0/978Lbw4ZgXo3I/xviTRcYm/4FyKHQlq1Y88t6I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IvVFKkv0y7RMU+eaE2LIeo4djwoZbbGTHaX2CJK1jB7tjq0xavmcbFOpZj+mqd+JO UvkAOKM/PeelnOWhkBF4QCbHiaIkkCn+kjry62fA2U84/pN5nHwHWDdHr4ss3DMaFo xoGtakOnbouoRNfdhTcN+yNWnog4Hrq1jNeJm7jI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Pali=20Roh=C3=A1r?= , =?UTF-8?q?Marek=20Beh=C3=BAn?= , Lorenzo Pieralisi , Russell King Subject: [PATCH 5.4 098/355] PCI: pci-bridge-emul: Fix emulation of W1C bits Date: Mon, 15 Nov 2021 18:00:22 +0100 Message-Id: <20211115165316.972895179@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165313.549179499@linuxfoundation.org> References: <20211115165313.549179499@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marek Behún commit 7a41ae80bdcb17e14dd7d83239b8a0cf368f18be upstream. The pci_bridge_emul_conf_write() function correctly clears W1C bits in cfgspace cache, but it does not inform the underlying implementation about the clear request: the .write_op() method is given the value with these bits cleared. This is wrong if the .write_op() needs to know which bits were requested to be cleared. Fix the value to be passed into the .write_op() method to have requested W1C bits set, so that it can clear them. Both pci-bridge-emul users (mvebu and aardvark) are compatible with this change. Link: https://lore.kernel.org/r/20211028185659.20329-2-kabel@kernel.org Fixes: 23a5fba4d941 ("PCI: Introduce PCI bridge emulated config space common logic") Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Cc: stable@vger.kernel.org Cc: Russell King Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pci-bridge-emul.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- a/drivers/pci/pci-bridge-emul.c +++ b/drivers/pci/pci-bridge-emul.c @@ -432,8 +432,21 @@ int pci_bridge_emul_conf_write(struct pc /* Clear the W1C bits */ new &= ~((value << shift) & (behavior[reg / 4].w1c & mask)); + /* Save the new value with the cleared W1C bits into the cfgspace */ cfgspace[reg / 4] = cpu_to_le32(new); + /* + * Clear the W1C bits not specified by the write mask, so that the + * write_op() does not clear them. + */ + new &= ~(behavior[reg / 4].w1c & ~mask); + + /* + * Set the W1C bits specified by the write mask, so that write_op() + * knows about that they are to be cleared. + */ + new |= (value << shift) & (behavior[reg / 4].w1c & mask); + if (write_op) write_op(bridge, reg, old, new, mask);