From: "Luis R. Rodriguez" <[email protected]> This driver sadly does not have the MMIO registers and WC desired areas (PIO buffers in this case) properly split up and addressing a split is considerable work, as such this such requires using the __arch_phys_wc_add() call to ensure write combining is enforced using MTRR on x86 even when PAT is available.
Cc: Rickard Strandqvist <[email protected]> Cc: Mike Marciniszyn <[email protected]> Cc: Roland Dreier <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Suresh Siddha <[email protected]> Cc: Venkatesh Pallipadi <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: Dave Airlie <[email protected]> Cc: Bjorn Helgaas <[email protected]> Cc: Antonino Daplas <[email protected]> Cc: Jean-Christophe Plagniol-Villard <[email protected]> Cc: Tomi Valkeinen <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Michael S. Tsirkin <[email protected]> Cc: [email protected] Cc: Stefan Bader <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Roger Pau Monné <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Signed-off-by: Luis R. Rodriguez <[email protected]> --- drivers/infiniband/hw/ipath/ipath_driver.c | 7 ++-- drivers/infiniband/hw/ipath/ipath_kernel.h | 4 +-- drivers/infiniband/hw/ipath/ipath_wc_x86_64.c | 47 ++++++++++----------------- 3 files changed, 20 insertions(+), 38 deletions(-) diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c index bd0caed..464f39c 100644 --- a/drivers/infiniband/hw/ipath/ipath_driver.c +++ b/drivers/infiniband/hw/ipath/ipath_driver.c @@ -542,6 +542,7 @@ 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 pio on a separate ioremap_wc() */ dd->ipath_kregbase = ioremap_nocache(addr, len); #endif @@ -587,12 +588,8 @@ 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..88709c1 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 <linux/pci.h> -#include <asm/mtrr.h> #include <asm/processor.h> #include "ipath_kernel.h" @@ -122,27 +121,26 @@ 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) { + /* + * If MTRR is not available on an architecture + * or if it could not be enabled at run time + * folks who care should work towards the + * ioremap_wc() split. + */ + if (!dd->wc_cookie) + ipath_dev_err(dd, "System does not support MTRR\n"); + else { + ipath_dev_err(dd, "Seting mtrr failed on PIO buffers\n"); + ret = -EINVAL; + } + } else + ipath_cdbg(VERBOSE, "Set mtrr for chip to WC\n"); } return ret; @@ -154,16 +152,5 @@ 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 [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
