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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, 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 4C7C0C433B4 for ; Wed, 5 May 2021 16:39:37 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DB28D619AF for ; Wed, 5 May 2021 16:39:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DB28D619AF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 86DAE83639; Wed, 5 May 2021 16:39:36 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id tURMrtDldLZR; Wed, 5 May 2021 16:39:35 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp1.osuosl.org (Postfix) with ESMTP id 2AD9B83486; Wed, 5 May 2021 16:39:35 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 17C5CC000D; Wed, 5 May 2021 16:39:35 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 8C461C0001 for ; Wed, 5 May 2021 16:39:33 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 7BC0F40445 for ; Wed, 5 May 2021 16:39:33 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp4.osuosl.org (amavisd-new); dkim=pass (2048-bit key) header.d=kernel.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QfX28mx7FJe5 for ; Wed, 5 May 2021 16:39:32 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp4.osuosl.org (Postfix) with ESMTPS id 3A0AD40411 for ; Wed, 5 May 2021 16:39:32 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 62EE4619AD; Wed, 5 May 2021 16:39:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620232771; bh=TlW828ly46jTTIUlPqwNRPDzw9XVkdGxE839ceIld94=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TsjShGjcZ5tsEi7T82aJVlkOXrWmEOoNUm3htWBCUwDBG+DtKsIiOF3IgMchiyOHB AR6GaxEBoDtM8M9PK46uN/nwYpP+8dV9Yalr3qThB7cya1hcpo0IokT0K5SVSImO8h YRN2hpxpY1w4mQG6LaQuD00VpfNXzrvwF6dBFWA8ykBZsZyGJ4parOU1qpiHVNVbxJ XtIkzut3QvEZPqlaX8rtULuvW3ILywSTTgTAbR3E8Eco9aI1m/3A70HiD8+xt4XDta JtYsPB4l9P0fHPxkvSHdRUK3Ut+DVZOR9j6rgAjtRIKOBeDrPuDuppNyxzPwr5ihhF VWiIjNC4Q1uSg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 24/46] Revert "iommu/amd: Fix performance counter initialization" Date: Wed, 5 May 2021 12:38:34 -0400 Message-Id: <20210505163856.3463279-24-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210505163856.3463279-1-sashal@kernel.org> References: <20210505163856.3463279-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Cc: Sasha Levin , Paul Menzel , Joerg Roedel , David Coe , Alexander Monakov , iommu@lists.linux-foundation.org, Shuah Khan , Tj X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" From: Paul Menzel [ Upstream commit 715601e4e36903a653cd4294dfd3ed0019101991 ] This reverts commit 6778ff5b21bd8e78c8bd547fd66437cf2657fd9b. The original commit tries to address an issue, where PMC power-gating causing the IOMMU PMC pre-init test to fail on certain desktop/mobile platforms where the power-gating is normally enabled. There have been several reports that the workaround still does not guarantee to work, and can add up to 100 ms (on the worst case) to the boot process on certain platforms such as the MSI B350M MORTAR with AMD Ryzen 3 2200G. Therefore, revert this commit as a prelude to removing the pre-init test. Link: https://lore.kernel.org/linux-iommu/alpine.LNX.3.20.13.2006030935570.3181@monopod.intra.ispras.ru/ Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201753 Cc: Tj (Elloe Linux) Cc: Shuah Khan Cc: Alexander Monakov Cc: David Coe Signed-off-by: Paul Menzel Signed-off-by: Suravee Suthikulpanit Link: https://lore.kernel.org/r/20210409085848.3908-2-suravee.suthikulpanit@amd.com Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin --- drivers/iommu/amd_iommu_init.c | 45 +++++++++------------------------- 1 file changed, 11 insertions(+), 34 deletions(-) diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index ad714ff375f8..31d7e2d4f304 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -12,7 +12,6 @@ #include #include #include -#include #include #include #include @@ -254,8 +253,6 @@ static enum iommu_init_state init_state = IOMMU_START_STATE; static int amd_iommu_enable_interrupts(void); static int __init iommu_go_to_state(enum iommu_init_state state); static void init_device_table_dma(void); -static int iommu_pc_get_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr, - u8 fxn, u64 *value, bool is_write); static bool amd_iommu_pre_enabled = true; @@ -1675,11 +1672,13 @@ static int __init init_iommu_all(struct acpi_table_header *table) return 0; } -static void __init init_iommu_perf_ctr(struct amd_iommu *iommu) +static int iommu_pc_get_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr, + u8 fxn, u64 *value, bool is_write); + +static void init_iommu_perf_ctr(struct amd_iommu *iommu) { - int retry; struct pci_dev *pdev = iommu->dev; - u64 val = 0xabcd, val2 = 0, save_reg, save_src; + u64 val = 0xabcd, val2 = 0, save_reg = 0; if (!iommu_feature(iommu, FEATURE_PC)) return; @@ -1687,39 +1686,17 @@ static void __init init_iommu_perf_ctr(struct amd_iommu *iommu) amd_iommu_pc_present = true; /* save the value to restore, if writable */ - if (iommu_pc_get_set_reg(iommu, 0, 0, 0, &save_reg, false) || - iommu_pc_get_set_reg(iommu, 0, 0, 8, &save_src, false)) - goto pc_false; - - /* - * Disable power gating by programing the performance counter - * source to 20 (i.e. counts the reads and writes from/to IOMMU - * Reserved Register [MMIO Offset 1FF8h] that are ignored.), - * which never get incremented during this init phase. - * (Note: The event is also deprecated.) - */ - val = 20; - if (iommu_pc_get_set_reg(iommu, 0, 0, 8, &val, true)) + if (iommu_pc_get_set_reg(iommu, 0, 0, 0, &save_reg, false)) goto pc_false; /* Check if the performance counters can be written to */ - val = 0xabcd; - for (retry = 5; retry; retry--) { - if (iommu_pc_get_set_reg(iommu, 0, 0, 0, &val, true) || - iommu_pc_get_set_reg(iommu, 0, 0, 0, &val2, false) || - val2) - break; - - /* Wait about 20 msec for power gating to disable and retry. */ - msleep(20); - } - - /* restore */ - if (iommu_pc_get_set_reg(iommu, 0, 0, 0, &save_reg, true) || - iommu_pc_get_set_reg(iommu, 0, 0, 8, &save_src, true)) + if ((iommu_pc_get_set_reg(iommu, 0, 0, 0, &val, true)) || + (iommu_pc_get_set_reg(iommu, 0, 0, 0, &val2, false)) || + (val != val2)) goto pc_false; - if (val != val2) + /* restore */ + if (iommu_pc_get_set_reg(iommu, 0, 0, 0, &save_reg, true)) goto pc_false; pci_info(pdev, "IOMMU performance counters supported\n"); -- 2.30.2 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu