From patchwork Mon Oct 4 18:59:31 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Garrett X-Patchwork-Id: 229851 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o94IxuRI021107 for ; Mon, 4 Oct 2010 18:59:56 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932252Ab0JDS7z (ORCPT ); Mon, 4 Oct 2010 14:59:55 -0400 Received: from mx1.redhat.com ([209.132.183.28]:23264 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932247Ab0JDS7y (ORCPT ); Mon, 4 Oct 2010 14:59:54 -0400 Received: from int-mx08.intmail.prod.int.phx2.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o94IxouB025966 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 4 Oct 2010 14:59:51 -0400 Received: from cavan.codon.org.uk ([10.3.113.5]) by int-mx08.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o94IxnYb018655 (version=TLSv1/SSLv3 cipher=AES256-SHA bits=256 verify=NO); Mon, 4 Oct 2010 14:59:50 -0400 Received: from nat-pool-rdu.redhat.com ([66.187.233.202] helo=localhost.localdomain) by cavan.codon.org.uk with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.69) (envelope-from ) id 1P2qGG-0003Xg-Dx; Mon, 04 Oct 2010 19:59:45 +0100 From: Matthew Garrett To: Joerg.Roedel@amd.com Cc: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, jbarnes@virtuousgeek.org, stable@kernel.org, Matthew Garrett Subject: [PATCH v2] x86: Reenable the AMD IOMMU if it's mysteriously vanished over suspend Date: Mon, 4 Oct 2010 14:59:31 -0400 Message-Id: <1286218771-5934-1-git-send-email-mjg@redhat.com> In-Reply-To: <20101004134339.GT9817@amd.com> References: <20101004134339.GT9817@amd.com> X-SA-Do-Not-Run: Yes X-SA-Exim-Connect-IP: 66.187.233.202 X-SA-Exim-Mail-From: mjg@redhat.com X-SA-Exim-Scanned: No (on cavan.codon.org.uk); SAEximRunCond expanded to false X-Scanned-By: MIMEDefang 2.67 on 10.5.11.21 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Mon, 04 Oct 2010 18:59:56 +0000 (UTC) diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h index 0861618..bdd20c8 100644 --- a/arch/x86/include/asm/amd_iommu_types.h +++ b/arch/x86/include/asm/amd_iommu_types.h @@ -416,13 +416,22 @@ struct amd_iommu { struct dma_ops_domain *default_dom; /* - * This array is required to work around a potential BIOS bug. - * The BIOS may miss to restore parts of the PCI configuration - * space when the system resumes from S3. The result is that the - * IOMMU does not execute commands anymore which leads to system - * failure. + * We can't rely on the BIOS to restore all values on reinit, so we + * need to stash them */ - u32 cache_cfg[4]; + + /* The iommu BAR */ + u32 stored_addr_lo; + u32 stored_addr_hi; + + /* + * Each iommu has 6 l1s, each of which is documented as having 0x12 + * registers + */ + u32 stored_l1[6][0x12]; + + /* The l2 indirect registers */ + u32 stored_l2[0x83]; }; /* diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index 5a170cb..44710d8 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -194,6 +194,39 @@ static inline unsigned long tbl_size(int entry_size) return 1UL << shift; } +/* Access to l1 and l2 indexed register spaces */ + +static u32 iommu_read_l1(struct amd_iommu *iommu, u16 l1, u8 address) +{ + u32 val; + + pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16)); + pci_read_config_dword(iommu->dev, 0xfc, &val); + return val; +} + +static void iommu_write_l1(struct amd_iommu *iommu, u16 l1, u8 address, u32 val) +{ + pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16 | 1 << 31)); + pci_write_config_dword(iommu->dev, 0xfc, val); + pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16)); +} + +static u32 iommu_read_l2(struct amd_iommu *iommu, u8 address) +{ + u32 val; + + pci_write_config_dword(iommu->dev, 0xf0, address); + pci_read_config_dword(iommu->dev, 0xf4, &val); + return val; +} + +static void iommu_write_l2(struct amd_iommu *iommu, u8 address, u32 val) +{ + pci_write_config_dword(iommu->dev, 0xf0, (address | 1 << 8)); + pci_write_config_dword(iommu->dev, 0xf4, val); +} + /**************************************************************************** * * AMD IOMMU MMIO register space handling functions @@ -619,6 +652,7 @@ static void __init init_iommu_from_pci(struct amd_iommu *iommu) { int cap_ptr = iommu->cap_ptr; u32 range, misc; + int i, j; pci_read_config_dword(iommu->dev, cap_ptr + MMIO_CAP_HDR_OFFSET, &iommu->cap); @@ -633,12 +667,29 @@ static void __init init_iommu_from_pci(struct amd_iommu *iommu) MMIO_GET_LD(range)); iommu->evt_msi_num = MMIO_MSI_NUM(misc); - if (is_rd890_iommu(iommu->dev)) { - pci_read_config_dword(iommu->dev, 0xf0, &iommu->cache_cfg[0]); - pci_read_config_dword(iommu->dev, 0xf4, &iommu->cache_cfg[1]); - pci_read_config_dword(iommu->dev, 0xf8, &iommu->cache_cfg[2]); - pci_read_config_dword(iommu->dev, 0xfc, &iommu->cache_cfg[3]); - } + if (!is_rd890_iommu(iommu->dev)) + return; + + /* + * Some rd890 systems may not be fully reconfigured by the BIOS, so + * it's necessary for us to store this information so it can be + * reprogrammed on resume + */ + + pci_read_config_dword(iommu->dev, iommu->cap_ptr + 4, + &iommu->stored_addr_lo); + pci_read_config_dword(iommu->dev, iommu->cap_ptr + 8, + &iommu->stored_addr_hi); + + /* Low bit locks writes to configuration space */ + iommu->stored_addr_lo &= ~1; + + for (i = 0; i < 6; i++) + for (j = 0; j < 0x12; j++) + iommu->stored_l1[i][j] = iommu_read_l1(iommu, i, j); + + for (i = 0; i < 0x83; i++) + iommu->stored_l2[i] = iommu_read_l2(iommu, i); } /* @@ -1127,14 +1178,53 @@ static void iommu_init_flags(struct amd_iommu *iommu) iommu_feature_enable(iommu, CONTROL_COHERENT_EN); } -static void iommu_apply_quirks(struct amd_iommu *iommu) +static void iommu_apply_resume_quirks(struct amd_iommu *iommu) { - if (is_rd890_iommu(iommu->dev)) { - pci_write_config_dword(iommu->dev, 0xf0, iommu->cache_cfg[0]); - pci_write_config_dword(iommu->dev, 0xf4, iommu->cache_cfg[1]); - pci_write_config_dword(iommu->dev, 0xf8, iommu->cache_cfg[2]); - pci_write_config_dword(iommu->dev, 0xfc, iommu->cache_cfg[3]); - } + int i, j; + u32 ioc_feature_control; + struct pci_dev *pdev = NULL; + + /* RD890 BIOSes may not have completely reconfigured the iommu */ + if (!is_rd890_iommu(iommu->dev)) + return; + + /* + * First, we need to ensure that the iommu is enabled. This is + * controlled by a register in the northbridge + */ + pdev = pci_get_bus_and_slot(iommu->dev->bus->number, PCI_DEVFN(0, 0)); + + if (!pdev) + return; + + /* Select Northbridge indirect register 0x75 and enable writing */ + pci_write_config_dword(pdev, 0x60, 0x75 | (1 << 7)); + pci_read_config_dword(pdev, 0x64, &ioc_feature_control); + + /* Enable the iommu */ + if (!(ioc_feature_control & 0x1)) + pci_write_config_dword(pdev, 0x64, ioc_feature_control | 1); + + pci_dev_put(pdev); + + /* Restore the iommu BAR */ + pci_write_config_dword(iommu->dev, iommu->cap_ptr + 4, + iommu->stored_addr_lo); + pci_write_config_dword(iommu->dev, iommu->cap_ptr + 8, + iommu->stored_addr_hi); + + /* Restore the l1 indirect regs for each of the 6 l1s */ + for (i = 0; i < 6; i++) + for (j = 0; j < 0x12; j++) + iommu_write_l1(iommu, i, j, iommu->stored_l1[i][j]); + + /* Restore the l2 indirect regs */ + for (i = 0; i < 0x83; i++) + iommu_write_l2(iommu, i, iommu->stored_l2[i]); + + /* Lock PCI setup registers */ + pci_write_config_dword(iommu->dev, iommu->cap_ptr + 4, + iommu->stored_addr_lo | 1); } /* @@ -1147,7 +1237,6 @@ static void enable_iommus(void) for_each_iommu(iommu) { iommu_disable(iommu); - iommu_apply_quirks(iommu); iommu_init_flags(iommu); iommu_set_device_table(iommu); iommu_enable_command_buffer(iommu); @@ -1173,6 +1262,11 @@ static void disable_iommus(void) static int amd_iommu_resume(struct sys_device *dev) { + struct amd_iommu *iommu; + + for_each_iommu(iommu) + iommu_apply_resume_quirks(iommu); + /* re-load the hardware */ enable_iommus();