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=-13.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 96556C433E1 for ; Thu, 16 Jul 2020 07:28:32 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 4896A206F5 for ; Thu, 16 Jul 2020 07:28:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="NcylmrG1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4896A206F5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4B6m7y2Dg3zDqHv for ; Thu, 16 Jul 2020 17:28:30 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:4864:20::f43; helo=mail-qv1-xf43.google.com; envelope-from=leobras.c@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=NcylmrG1; dkim-atps=neutral Received: from mail-qv1-xf43.google.com (mail-qv1-xf43.google.com [IPv6:2607:f8b0:4864:20::f43]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4B6lvY3SqZzDqv6 for ; Thu, 16 Jul 2020 17:17:45 +1000 (AEST) Received: by mail-qv1-xf43.google.com with SMTP id el4so2251596qvb.13 for ; Thu, 16 Jul 2020 00:17:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=SXoTy1h4V7NJb4O+XXmTDMHlH/lLg962odT4Jny1J3o=; b=NcylmrG1390JPm0HVgxReAnsbpfxRFkncQoQ2+ihYB432hnVUkiUStvHlIqllyGsrF 6lIlY/OOxjlCVZLGW4zY/UZf5vaymbGcVLPmqW4U4/QccME5iZacDg6z1jJlrz7PTe8G 6tAdn4T+KTZX47/Gsxio13/Pw1P1+OLkKcG/vfSQs83xkMJfnXt6r/IATvuMCsVoZJ5O lNcVpkvrwKtrX3YBfWRoFHgW90jTcOxgGGmzXHWC8Ws3KJnJaLSCLMEeZ3Z+Rf5CKHAC nSXk7CSHUlCI94sBxJsAqk1T+WLJ4Hc5xbJHoX9onTqytSnas+uIcXqE0L9EuCZ3bRdI Bf8w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=SXoTy1h4V7NJb4O+XXmTDMHlH/lLg962odT4Jny1J3o=; b=YjUH3yU4XKnzLXGx/MTDejJ05VXJM5npozdpIjhl7MelvfKG+W3VAoSKALlYQ+CLnR PaTvXLDbZe+qfs1SxKfVNowJjkbSGa8Z6a3FdHqH7VlT+xLXhwHaklmzjry8iCYn07+d 56NQMAVOzCPc9piAUObcw+ChhBysTNg5HlBicr1YN59KYiaf2LqdoHwyrJ8Tjehg37jz vph2FFhsJpA6HvmzyKOn4FqJOD5rBlLefjUROkS++S2jOSxoFfT1lJLaNf9bTPgKnzd+ y/NfZg2DCGNpweCXkvoqwK1OlIbQpmCIUExS4cMkZ0hF7hgW9XxnDvMMUjU/NuZDARAB G2mg== X-Gm-Message-State: AOAM5320quP/ZGqBDBem4Br5MibQ44HbV4FSXcMDlNzvtGII1hsDaAPG qBzeibB2sNRh7L0LjL+/DUc= X-Google-Smtp-Source: ABdhPJxN6nicLFqpJlfCcP6jFOV7E5kTOM49yMkA9W5qvWRJir1dsdqIwPHNpUdpbMqzUWf6j1KvnA== X-Received: by 2002:ad4:5511:: with SMTP id az17mr2954877qvb.159.1594883863178; Thu, 16 Jul 2020 00:17:43 -0700 (PDT) Received: from LeoBras.ibmuc.com (200-236-239-31.dynamic.desktop.com.br. [200.236.239.31]) by smtp.gmail.com with ESMTPSA id a5sm6637989qtd.84.2020.07.16.00.17.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Jul 2020 00:17:42 -0700 (PDT) From: Leonardo Bras To: Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Alexey Kardashevskiy , Joel Stanley , Christophe Leroy , Leonardo Bras , Thiago Jung Bauermann , Ram Pai , Brian King Subject: [PATCH v4 4/7] powerpc/pseries/iommu: Remove default DMA window before creating DDW Date: Thu, 16 Jul 2020 04:16:56 -0300 Message-Id: <20200716071658.467820-5-leobras.c@gmail.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200716071658.467820-1-leobras.c@gmail.com> References: <20200716071658.467820-1-leobras.c@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On LoPAR "DMA Window Manipulation Calls", it's recommended to remove the default DMA window for the device, before attempting to configure a DDW, in order to make the maximum resources available for the next DDW to be created. This is a requirement for using DDW on devices in which hypervisor allows only one DMA window. If setting up a new DDW fails anywhere after the removal of this default DMA window, it's needed to restore the default DMA window. For this, an implementation of ibm,reset-pe-dma-windows rtas call is needed: Platforms supporting the DDW option starting with LoPAR level 2.7 implement ibm,ddw-extensions. The first extension available (index 2) carries the token for ibm,reset-pe-dma-windows rtas call, which is used to restore the default DMA window for a device, if it has been deleted. It does so by resetting the TCE table allocation for the PE to it's boot time value, available in "ibm,dma-window" device tree node. Signed-off-by: Leonardo Bras --- arch/powerpc/platforms/pseries/iommu.c | 73 +++++++++++++++++++++++--- 1 file changed, 66 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index 4e33147825cc..fc8d0555e2e9 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -1066,6 +1066,38 @@ static phys_addr_t ddw_memory_hotplug_max(void) return max_addr; } +/* + * Platforms supporting the DDW option starting with LoPAR level 2.7 implement + * ibm,ddw-extensions, which carries the rtas token for + * ibm,reset-pe-dma-windows. + * That rtas-call can be used to restore the default DMA window for the device. + */ +static void reset_dma_window(struct pci_dev *dev, struct device_node *par_dn) +{ + int ret; + u32 cfg_addr, reset_dma_win; + u64 buid; + struct device_node *dn; + struct pci_dn *pdn; + + ret = ddw_read_ext(par_dn, DDW_EXT_RESET_DMA_WIN, &reset_dma_win); + if (ret) + return; + + dn = pci_device_to_OF_node(dev); + pdn = PCI_DN(dn); + buid = pdn->phb->buid; + cfg_addr = ((pdn->busno << 16) | (pdn->devfn << 8)); + + ret = rtas_call(reset_dma_win, 3, 1, NULL, cfg_addr, BUID_HI(buid), + BUID_LO(buid)); + if (ret) + dev_info(&dev->dev, + "ibm,reset-pe-dma-windows(%x) %x %x %x returned %d ", + reset_dma_win, cfg_addr, BUID_HI(buid), BUID_LO(buid), + ret); +} + /* * If the PE supports dynamic dma windows, and there is space for a table * that can map all pages in a linear offset, then setup such a table, @@ -1090,6 +1122,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) struct property *win64; struct dynamic_dma_window_prop *ddwprop; struct failed_ddw_pdn *fpdn; + bool default_win_removed = false; mutex_lock(&direct_window_init_mutex); @@ -1133,14 +1166,38 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) if (ret != 0) goto out_failed; + /* + * If there is no window available, remove the default DMA window, + * if it's present. This will make all the resources available to the + * new DDW window. + * If anything fails after this, we need to restore it, so also check + * for extensions presence. + */ if (query.windows_available == 0) { - /* - * no additional windows are available for this device. - * We might be able to reallocate the existing window, - * trading in for a larger page size. - */ - dev_dbg(&dev->dev, "no free dynamic windows"); - goto out_failed; + struct property *default_win; + int reset_win_ext; + + default_win = of_find_property(pdn, "ibm,dma-window", NULL); + if (!default_win) + goto out_failed; + + reset_win_ext = ddw_read_ext(pdn, DDW_EXT_RESET_DMA_WIN, NULL); + if (reset_win_ext) + goto out_failed; + + remove_dma_window(pdn, ddw_avail, default_win); + default_win_removed = true; + + /* Query again, to check if the window is available */ + ret = query_ddw(dev, ddw_avail, &query, pdn); + if (ret != 0) + goto out_failed; + + if (query.windows_available == 0) { + /* no windows are available for this device. */ + dev_dbg(&dev->dev, "no free dynamic windows"); + goto out_failed; + } } if (query.page_size & 4) { page_shift = 24; /* 16MB */ @@ -1231,6 +1288,8 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) kfree(win64); out_failed: + if (default_win_removed) + reset_dma_window(dev, pdn); fpdn = kzalloc(sizeof(*fpdn), GFP_KERNEL); if (!fpdn) -- 2.25.4