Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754125AbbDVT3F (ORCPT ); Wed, 22 Apr 2015 15:29:05 -0400 Received: from mail-pd0-f173.google.com ([209.85.192.173]:35291 "EHLO mail-pd0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754003AbbDVT3A (ORCPT ); Wed, 22 Apr 2015 15:29:00 -0400 From: "Luis R. Rodriguez" To: dledford@redhat.com, infinipath@intel.com, roland@kernel.org, sean.hefty@intel.com, hal.rosenstock@gmail.com, linux-rdma@vger.kernel.org Cc: luto@amacapital.net, mst@redhat.com, linux-kernel@vger.kernel.org, "Luis R. Rodriguez" , Suresh Siddha , Rickard Strandqvist , Mike Marciniszyn , Roland Dreier , Ingo Molnar , Linus Torvalds , Thomas Gleixner , Juergen Gross , Daniel Vetter , Dave Airlie , Bjorn Helgaas , Antonino Daplas , Jean-Christophe Plagniol-Villard , Tomi Valkeinen , =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Mel Gorman , Vlastimil Babka , Borislav Petkov , Davidlohr Bueso , Dave Hansen , Arnd Bergmann , Stefan Bader , konrad.wilk@oracle.com, ville.syrjala@linux.intel.com, david.vrabel@citrix.com, jbeulich@suse.com, toshi.kani@hp.com, =?UTF-8?q?Roger=20Pau=20Monn=C3=A9?= , linux-fbdev@vger.kernel.org, xen-devel@lists.xensource.com Subject: [PATCH] IB/ipath: use arch_phys_wc_add() and require PAT disabled Date: Wed, 22 Apr 2015 12:26:35 -0700 Message-Id: <1429730795-6721-1-git-send-email-mcgrof@do-not-panic.com> X-Mailer: git-send-email 2.1.0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7658 Lines: 219 From: "Luis R. Rodriguez" We are burrying direct access to MTRR code support on x86 in order to take advantage of PAT. In the future we also want to make the default behaviour of ioremap_nocache() to use strong UC, use of mtrr_add() on those systems would make write-combining void. In order to help both enable us to later make strong UC default and in order to phase out direct MTRR access code port the driver over to arch_phys_wc_add() and annotate that the device driver requires systems to boot with PAT disabled, with the nopat kernel parameter. This is a worthy compromise given that the ipath device driver powers the old HTX bus cards that only work in AMD systems, while the newer IB/qib device driver powers all PCI-e cards. The ipath device driver is obsolete, hardware hard to find and because of this this its a reasonable compromise to make to require users of ipath to boot with nopat. Cc: Doug Ledford Cc: Hal Rosenstock Cc: Sean Hefty Cc: Suresh Siddha Cc: Rickard Strandqvist Cc: Mike Marciniszyn Cc: Roland Dreier Cc: Andy Lutomirski Cc: Ingo Molnar Cc: Linus Torvalds Cc: Thomas Gleixner Cc: Juergen Gross Cc: Daniel Vetter Cc: Dave Airlie Cc: Bjorn Helgaas Cc: Antonino Daplas Cc: Jean-Christophe Plagniol-Villard Cc: Tomi Valkeinen Cc: Ville Syrjälä Cc: Mel Gorman Cc: Vlastimil Babka Cc: Borislav Petkov Cc: Davidlohr Bueso Cc: Dave Hansen Cc: Arnd Bergmann Cc: Michael S. Tsirkin Cc: Stefan Bader Cc: konrad.wilk@oracle.com Cc: ville.syrjala@linux.intel.com Cc: david.vrabel@citrix.com Cc: jbeulich@suse.com Cc: toshi.kani@hp.com Cc: Roger Pau Monné Cc: infinipath@intel.com Cc: linux-rdma@vger.kernel.org Cc: linux-fbdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xensource.com Signed-off-by: Luis R. Rodriguez --- drivers/infiniband/hw/ipath/Kconfig | 3 ++ drivers/infiniband/hw/ipath/ipath_driver.c | 18 +++++++---- drivers/infiniband/hw/ipath/ipath_kernel.h | 4 +-- drivers/infiniband/hw/ipath/ipath_wc_x86_64.c | 43 ++++++--------------------- 4 files changed, 26 insertions(+), 42 deletions(-) diff --git a/drivers/infiniband/hw/ipath/Kconfig b/drivers/infiniband/hw/ipath/Kconfig index 1d9bb11..8fe54ff 100644 --- a/drivers/infiniband/hw/ipath/Kconfig +++ b/drivers/infiniband/hw/ipath/Kconfig @@ -9,3 +9,6 @@ config INFINIBAND_IPATH as IP-over-InfiniBand as well as with userspace applications (in conjunction with InfiniBand userspace access). For QLogic PCIe QLE based cards, use the QIB driver instead. + + If you have this hardware you will need to boot with PAT disabled + on your x86-64 systems, use the nopat kernel parameter. diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c index bd0caed..3ef592c 100644 --- a/drivers/infiniband/hw/ipath/ipath_driver.c +++ b/drivers/infiniband/hw/ipath/ipath_driver.c @@ -42,6 +42,9 @@ #include #include #include +#ifdef CONFIG_X86_64 +#include +#endif #include "ipath_kernel.h" #include "ipath_verbs.h" @@ -395,6 +398,14 @@ static int ipath_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) unsigned long long addr; u32 bar0 = 0, bar1 = 0; +#ifdef CONFIG_X86_64 + if (WARN(pat_enabled, + "ipath needs PAT disabled, boot with nopat kernel parameter\n")) { + ret = EINVAL; + goto bail; + } +#endif + dd = ipath_alloc_devdata(pdev); if (IS_ERR(dd)) { ret = PTR_ERR(dd); @@ -542,6 +553,7 @@ static int ipath_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) dd->ipath_kregbase = __ioremap(addr, len, (_PAGE_NO_CACHE|_PAGE_WRITETHRU)); #else + /* XXX: split this properly to enable on PAT */ dd->ipath_kregbase = ioremap_nocache(addr, len); #endif @@ -587,12 +599,8 @@ static int ipath_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) ret = ipath_enable_wc(dd); - if (ret) { - ipath_dev_err(dd, "Write combining not enabled " - "(err %d): performance may be poor\n", - -ret); + if (ret) ret = 0; - } ipath_verify_pioperf(dd); diff --git a/drivers/infiniband/hw/ipath/ipath_kernel.h b/drivers/infiniband/hw/ipath/ipath_kernel.h index e08db70..f0f9471 100644 --- a/drivers/infiniband/hw/ipath/ipath_kernel.h +++ b/drivers/infiniband/hw/ipath/ipath_kernel.h @@ -463,9 +463,7 @@ struct ipath_devdata { /* offset in HT config space of slave/primary interface block */ u8 ipath_ht_slave_off; /* for write combining settings */ - unsigned long ipath_wc_cookie; - unsigned long ipath_wc_base; - unsigned long ipath_wc_len; + int wc_cookie; /* ref count for each pkey */ atomic_t ipath_pkeyrefs[4]; /* shadow copy of struct page *'s for exp tid pages */ diff --git a/drivers/infiniband/hw/ipath/ipath_wc_x86_64.c b/drivers/infiniband/hw/ipath/ipath_wc_x86_64.c index 70c1f3a..7b6e4c8 100644 --- a/drivers/infiniband/hw/ipath/ipath_wc_x86_64.c +++ b/drivers/infiniband/hw/ipath/ipath_wc_x86_64.c @@ -37,7 +37,6 @@ */ #include -#include #include #include "ipath_kernel.h" @@ -122,27 +121,14 @@ int ipath_enable_wc(struct ipath_devdata *dd) } if (!ret) { - int cookie; - ipath_cdbg(VERBOSE, "Setting mtrr for chip to WC " - "(addr %llx, len=0x%llx)\n", - (unsigned long long) pioaddr, - (unsigned long long) piolen); - cookie = mtrr_add(pioaddr, piolen, MTRR_TYPE_WRCOMB, 1); - if (cookie < 0) { - { - dev_info(&dd->pcidev->dev, - "mtrr_add() WC for PIO bufs " - "failed (%d)\n", - cookie); - ret = -EINVAL; - } - } else { - ipath_cdbg(VERBOSE, "Set mtrr for chip to WC, " - "cookie is %d\n", cookie); - dd->ipath_wc_cookie = cookie; - dd->ipath_wc_base = (unsigned long) pioaddr; - dd->ipath_wc_len = (unsigned long) piolen; - } + dd->wc_cookie = arch_phys_wc_add(pioaddr, piolen); + if (dd->wc_cookie < 0) { + ipath_dev_err(dd, "Seting mtrr failed on PIO buffers\n"); + ret = -ENODEV; + } else if (dd->wc_cookie == 0) + ipath_cdbg(VERBOSE, "Set mtrr for chip to WC not needed\n"); + else + ipath_cdbg(VERBOSE, "Set mtrr for chip to WC\n"); } return ret; @@ -154,16 +140,5 @@ int ipath_enable_wc(struct ipath_devdata *dd) */ void ipath_disable_wc(struct ipath_devdata *dd) { - if (dd->ipath_wc_cookie) { - int r; - ipath_cdbg(VERBOSE, "undoing WCCOMB on pio buffers\n"); - r = mtrr_del(dd->ipath_wc_cookie, dd->ipath_wc_base, - dd->ipath_wc_len); - if (r < 0) - dev_info(&dd->pcidev->dev, - "mtrr_del(%lx, %lx, %lx) failed: %d\n", - dd->ipath_wc_cookie, dd->ipath_wc_base, - dd->ipath_wc_len, r); - dd->ipath_wc_cookie = 0; /* even on failure */ - } + arch_phys_wc_del(dd->wc_cookie); } -- 2.3.2.209.gd67f9d5.dirty -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/