From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752832AbbJWU7g (ORCPT ); Fri, 23 Oct 2015 16:59:36 -0400 Received: from e17.ny.us.ibm.com ([129.33.205.207]:58328 "EHLO e17.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752347AbbJWU7e (ORCPT ); Fri, 23 Oct 2015 16:59:34 -0400 X-IBM-Helo: d01dlp02.pok.ibm.com X-IBM-MailFrom: nacc@linux.vnet.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org;sparclinux@vger.kernel.org Date: Fri, 23 Oct 2015 13:59:25 -0700 From: Nishanth Aravamudan To: Michael Ellerman Cc: Matthew Wilcox , Keith Busch , Benjamin Herrenschmidt , Paul Mackerras , Alexey Kardashevskiy , David Gibson , Christoph Hellwig , "David S. Miller" , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org Subject: [PATCH 4/7 v2] pseries/iommu: implement DDW-aware dma_get_page_shift Message-ID: <20151023205925.GF10197@linux.vnet.ibm.com> References: <20151023205420.GA10197@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151023205420.GA10197@linux.vnet.ibm.com> X-Operating-System: Linux 3.13.0-40-generic (x86_64) User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15102320-0041-0000-0000-000002095B0D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When DDW (Dynamic DMA Windows) are present for a device, we have stored the TCE (Translation Control Entry) size in a special device tree property. Check if we have enabled DDW for the device and return the TCE size from that property if present. If the property isn't present, fallback to looking the value up in struct iommu_table. If we don't find a iommu_table, fallback to the kernel's page size. Signed-off-by: Nishanth Aravamudan --- arch/powerpc/platforms/pseries/iommu.c | 36 ++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index 0946b98..1bf6471 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -1292,6 +1292,40 @@ static u64 dma_get_required_mask_pSeriesLP(struct device *dev) return dma_iommu_ops.get_required_mask(dev); } +static unsigned long dma_get_page_shift_pSeriesLP(struct device *dev) +{ + struct iommu_table *tbl; + + if (!disable_ddw && dev_is_pci(dev)) { + struct pci_dev *pdev = to_pci_dev(dev); + struct device_node *dn; + + dn = pci_device_to_OF_node(pdev); + + /* search upwards for ibm,dma-window */ + for (; dn && PCI_DN(dn) && !PCI_DN(dn)->table_group; + dn = dn->parent) + if (of_get_property(dn, "ibm,dma-window", NULL)) + break; + /* + * if there is a DDW configuration, the TCE shift is stored in + * the property + */ + if (dn && PCI_DN(dn)) { + const struct dynamic_dma_window_prop *direct64 = + of_get_property(dn, DIRECT64_PROPNAME, NULL); + if (direct64) + return be32_to_cpu(direct64->tce_shift); + } + } + + tbl = get_iommu_table_base(dev); + if (tbl) + return tbl->it_page_shift; + + return PAGE_SHIFT; +} + #else /* CONFIG_PCI */ #define pci_dma_bus_setup_pSeries NULL #define pci_dma_dev_setup_pSeries NULL @@ -1299,6 +1333,7 @@ static u64 dma_get_required_mask_pSeriesLP(struct device *dev) #define pci_dma_dev_setup_pSeriesLP NULL #define dma_set_mask_pSeriesLP NULL #define dma_get_required_mask_pSeriesLP NULL +#define dma_get_page_shift_pSeriesLP NULL #endif /* !CONFIG_PCI */ static int iommu_mem_notifier(struct notifier_block *nb, unsigned long action, @@ -1395,6 +1430,7 @@ void iommu_init_early_pSeries(void) pseries_pci_controller_ops.dma_dev_setup = pci_dma_dev_setup_pSeriesLP; ppc_md.dma_set_mask = dma_set_mask_pSeriesLP; ppc_md.dma_get_required_mask = dma_get_required_mask_pSeriesLP; + ppc_md.dma_get_page_shift = dma_get_page_shift_pSeriesLP; } else { pseries_pci_controller_ops.dma_bus_setup = pci_dma_bus_setup_pSeries; pseries_pci_controller_ops.dma_dev_setup = pci_dma_dev_setup_pSeries; -- 1.9.1