Commit Graph

127 Commits

Author SHA1 Message Date
Allen Hubbe e22e0b9dcf NTB: Differentiate transport link down messages
The same message "qp %d: Link Down\n" was printed at two locations in
ntb_transport.  Change the messages so they are distinct.

Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:06:19 -04:00
Dave Jiang dd5d4d8edb NTB: Check the device ID to set errata flags
Set errata flags for the specific device IDs to which they apply,
instead of the whole Xeon hardware class.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:06:14 -04:00
Dave Jiang 5ae0beb6bc NTB: Enable link for Intel root port mode in probe
Link training should be enabled in the driver probe for root port mode.
We should not have to wait for transport to be loaded for this to
happen.  Otherwise the ntb device will not show up on the transparent
bridge side of the link.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:06:08 -04:00
Dave Jiang 0f69a7dff9 NTB: Read peer info from local SPAD in transport
The transport was writing and then reading the peer scratch pad,
essentially reading what it just wrote instead of exchanging any
information with the peer.  The transport expects the peer values to be
the same as the local values, so this issue was not obvious.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:06:00 -04:00
Allen Hubbe e26a5843f7 NTB: Split ntb_hw_intel and ntb_transport drivers
Change ntb_hw_intel to use the new NTB hardware abstraction layer.

Split ntb_transport into its own driver.  Change it to use the new NTB
hardware abstraction layer.

Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:05:49 -04:00
Allen Hubbe a1bd3baeb2 NTB: Add NTB hardware abstraction layer
Abstract the NTB device behind a programming interface, so that it can
support different hardware and client drivers.

Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:04:44 -04:00
Allen Hubbe ec110bc7cc NTB: Move files in preparation for NTB abstraction
This patch only moves files to their new locations, before applying the
next two patches adding the NTB Abstraction layer.  Splitting this patch
from the next is intended make distinct which code is changed only due
to moving the files, versus which are substantial code changes in adding
the NTB Abstraction layer.

Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-02 10:09:23 -04:00
Linus Torvalds d8133356e9 PCI changes for the v4.2 merge window:
Enumeration
     - Move pci_ari_enabled() to global header (Alex Williamson)
     - Account for ARI in _PRT lookups (Alex Williamson)
     - Remove unused pci_scan_bus_parented() (Yijing Wang)
 
   Resource management
     - Use host bridge _CRS info on systems with >32 bit addressing (Bjorn Helgaas)
     - Use host bridge _CRS info on Foxconn K8M890-8237A (Bjorn Helgaas)
     - Fix pci_address_to_pio() conversion of CPU address to I/O port (Zhichang Yuan)
     - Add pci_bus_addr_t (Yinghai Lu)
 
   PCI device hotplug
     - Wait for pciehp command completion where necessary (Alex Williamson)
     - Drop pointless ACPI-based "slot detection" check (Rafael J. Wysocki)
     - Check ignore_hotplug for all downstream devices (Rafael J. Wysocki)
     - Propagate the "ignore hotplug" setting to parent (Rafael J. Wysocki)
     - Inline pciehp "handle event" functions into the ISR (Bjorn Helgaas)
     - Clean up pciehp debug logging (Bjorn Helgaas)
 
   Power management
     - Remove redundant PCIe port type checking (Yijing Wang)
     - Add dev->has_secondary_link to track downstream PCIe links (Yijing Wang)
     - Use dev->has_secondary_link to find downstream links for ASPM (Yijing Wang)
     - Drop __pci_disable_link_state() useless "force" parameter (Bjorn Helgaas)
     - Simplify Clock Power Management setting (Bjorn Helgaas)
 
   Virtualization
     - Add ACS quirks for Intel 9-series PCH root ports (Alex Williamson)
     - Add function 1 DMA alias quirk for Marvell 9120 (Sakari Ailus)
 
   MSI
     - Disable MSI at enumeration even if kernel doesn't support MSI (Michael S. Tsirkin)
     - Remove unused pci_msi_off() (Bjorn Helgaas)
     - Rename msi_set_enable(), msix_clear_and_set_ctrl() (Michael S.  Tsirkin)
     - Export pci_msi_set_enable(), pci_msix_clear_and_set_ctrl() (Michael S. Tsirkin)
     - Drop pci_msi_off() calls during probe (Michael S. Tsirkin)
 
   APM X-Gene host bridge driver
     - Add APM X-Gene v1 PCIe MSI/MSIX termination driver (Duc Dang)
     - Add APM X-Gene PCIe MSI DTS nodes (Duc Dang)
     - Disable Configuration Request Retry Status for v1 silicon (Duc Dang)
     - Allow config access to Root Port even when link is down (Duc Dang)
 
   Broadcom iProc host bridge driver
     - Allow override of device tree IRQ mapping function (Hauke Mehrtens)
     - Add BCMA PCIe driver (Hauke Mehrtens)
     - Directly add PCI resources (Hauke Mehrtens)
     - Free resource list after registration (Hauke Mehrtens)
 
   Freescale i.MX6 host bridge driver
     - Add speed change timeout message (Troy Kisky)
     - Rename imx6_pcie_start_link() to imx6_pcie_establish_link() (Bjorn Helgaas)
 
   Freescale Layerscape host bridge driver
     - Use dw_pcie_link_up() consistently (Bjorn Helgaas)
     - Factor out ls_pcie_establish_link() (Bjorn Helgaas)
 
   Marvell MVEBU host bridge driver
     - Remove mvebu_pcie_scan_bus() (Yijing Wang)
 
   NVIDIA Tegra host bridge driver
     - Remove tegra_pcie_scan_bus() (Yijing Wang)
 
   Synopsys DesignWare host bridge driver
     - Consolidate outbound iATU programming functions (Jisheng Zhang)
     - Use iATU0 for cfg and IO, iATU1 for MEM (Jisheng Zhang)
     - Add support for x8 links (Zhou Wang)
     - Wait for link to come up with consistent style (Bjorn Helgaas)
     - Use pci_scan_root_bus() for simplicity (Yijing Wang)
 
   TI DRA7xx host bridge driver
     - Use dw_pcie_link_up() consistently (Bjorn Helgaas)
 
   Miscellaneous
     - Include <linux/pci.h>, not <asm/pci.h> (Bjorn Helgaas)
     - Remove unnecessary #includes of <asm/pci.h> (Bjorn Helgaas)
     - Remove unused pcibios_select_root() (again) (Bjorn Helgaas)
     - Remove unused pci_dma_burst_advice() (Bjorn Helgaas)
     - xen/pcifront: Don't use deprecated function pci_scan_bus_parented() (Arnd Bergmann)
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Merge tag 'pci-v4.2-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for the v4.2 merge window:

  Enumeration
    - Move pci_ari_enabled() to global header (Alex Williamson)
    - Account for ARI in _PRT lookups (Alex Williamson)
    - Remove unused pci_scan_bus_parented() (Yijing Wang)

  Resource management
    - Use host bridge _CRS info on systems with >32 bit addressing (Bjorn Helgaas)
    - Use host bridge _CRS info on Foxconn K8M890-8237A (Bjorn Helgaas)
    - Fix pci_address_to_pio() conversion of CPU address to I/O port (Zhichang Yuan)
    - Add pci_bus_addr_t (Yinghai Lu)

  PCI device hotplug
    - Wait for pciehp command completion where necessary (Alex Williamson)
    - Drop pointless ACPI-based "slot detection" check (Rafael J. Wysocki)
    - Check ignore_hotplug for all downstream devices (Rafael J. Wysocki)
    - Propagate the "ignore hotplug" setting to parent (Rafael J. Wysocki)
    - Inline pciehp "handle event" functions into the ISR (Bjorn Helgaas)
    - Clean up pciehp debug logging (Bjorn Helgaas)

  Power management
    - Remove redundant PCIe port type checking (Yijing Wang)
    - Add dev->has_secondary_link to track downstream PCIe links (Yijing Wang)
    - Use dev->has_secondary_link to find downstream links for ASPM (Yijing Wang)
    - Drop __pci_disable_link_state() useless "force" parameter (Bjorn Helgaas)
    - Simplify Clock Power Management setting (Bjorn Helgaas)

  Virtualization
    - Add ACS quirks for Intel 9-series PCH root ports (Alex Williamson)
    - Add function 1 DMA alias quirk for Marvell 9120 (Sakari Ailus)

  MSI
    - Disable MSI at enumeration even if kernel doesn't support MSI (Michael S. Tsirkin)
    - Remove unused pci_msi_off() (Bjorn Helgaas)
    - Rename msi_set_enable(), msix_clear_and_set_ctrl() (Michael S.  Tsirkin)
    - Export pci_msi_set_enable(), pci_msix_clear_and_set_ctrl() (Michael S. Tsirkin)
    - Drop pci_msi_off() calls during probe (Michael S. Tsirkin)

  APM X-Gene host bridge driver
    - Add APM X-Gene v1 PCIe MSI/MSIX termination driver (Duc Dang)
    - Add APM X-Gene PCIe MSI DTS nodes (Duc Dang)
    - Disable Configuration Request Retry Status for v1 silicon (Duc Dang)
    - Allow config access to Root Port even when link is down (Duc Dang)

  Broadcom iProc host bridge driver
    - Allow override of device tree IRQ mapping function (Hauke Mehrtens)
    - Add BCMA PCIe driver (Hauke Mehrtens)
    - Directly add PCI resources (Hauke Mehrtens)
    - Free resource list after registration (Hauke Mehrtens)

  Freescale i.MX6 host bridge driver
    - Add speed change timeout message (Troy Kisky)
    - Rename imx6_pcie_start_link() to imx6_pcie_establish_link() (Bjorn Helgaas)

  Freescale Layerscape host bridge driver
    - Use dw_pcie_link_up() consistently (Bjorn Helgaas)
    - Factor out ls_pcie_establish_link() (Bjorn Helgaas)

  Marvell MVEBU host bridge driver
    - Remove mvebu_pcie_scan_bus() (Yijing Wang)

  NVIDIA Tegra host bridge driver
    - Remove tegra_pcie_scan_bus() (Yijing Wang)

  Synopsys DesignWare host bridge driver
    - Consolidate outbound iATU programming functions (Jisheng Zhang)
    - Use iATU0 for cfg and IO, iATU1 for MEM (Jisheng Zhang)
    - Add support for x8 links (Zhou Wang)
    - Wait for link to come up with consistent style (Bjorn Helgaas)
    - Use pci_scan_root_bus() for simplicity (Yijing Wang)

  TI DRA7xx host bridge driver
    - Use dw_pcie_link_up() consistently (Bjorn Helgaas)

  Miscellaneous
    - Include <linux/pci.h>, not <asm/pci.h> (Bjorn Helgaas)
    - Remove unnecessary #includes of <asm/pci.h> (Bjorn Helgaas)
    - Remove unused pcibios_select_root() (again) (Bjorn Helgaas)
    - Remove unused pci_dma_burst_advice() (Bjorn Helgaas)
    - xen/pcifront: Don't use deprecated function pci_scan_bus_parented() (Arnd Bergmann)"

* tag 'pci-v4.2-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (58 commits)
  PCI: pciehp: Inline the "handle event" functions into the ISR
  PCI: pciehp: Rename queue_interrupt_event() to pciehp_queue_interrupt_event()
  PCI: pciehp: Make queue_interrupt_event() void
  PCI: xgene: Allow config access to Root Port even when link is down
  PCI: xgene: Disable Configuration Request Retry Status for v1 silicon
  PCI: pciehp: Clean up debug logging
  x86/PCI: Use host bridge _CRS info on systems with >32 bit addressing
  PCI: imx6: Add #define PCIE_RC_LCSR
  PCI: imx6: Use "u32", not "uint32_t"
  PCI: Remove unused pci_scan_bus_parented()
  xen/pcifront: Don't use deprecated function pci_scan_bus_parented()
  PCI: imx6: Add speed change timeout message
  PCI/ASPM: Simplify Clock Power Management setting
  PCI: designware: Wait for link to come up with consistent style
  PCI: layerscape: Factor out ls_pcie_establish_link()
  PCI: layerscape: Use dw_pcie_link_up() consistently
  PCI: dra7xx: Use dw_pcie_link_up() consistently
  x86/PCI: Use host bridge _CRS info on Foxconn K8M890-8237A
  PCI: pciehp: Wait for hotplug command completion where necessary
  PCI: Remove unused pci_dma_burst_advice()
  ...
2015-06-23 13:41:24 -07:00
Daniel Verkamp ebaad1322d ntb: initialize max_mw for Atom before using it
Commit ab760a0 (ntb: Adding split BAR support for Haswell platforms)
changed ntb_device's mw from a fixed-size array into a pointer that is
allocated based on limits.max_mw; however, on Atom platforms, max_mw
is not initialized until ntb_device_setup(), which happens after the
allocation.

Fill out max_mw in ntb_atom_detect() to match ntb_xeon_detect(); this
happens before the use of max_mw in the ndev->mw allocation.

Fixes a null pointer dereference on Atom platforms with ntb hardware.

v2: fix typo (mw_max should be max_mw)

Signed-off-by: Daniel Verkamp <daniel.verkamp@intel.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-06-11 09:27:24 -04:00
Jon Mason 2f4eb6a80e ntb: iounmap MW reg and vbase in error path
The MW regbase and vbase(s) were not being freed if an error occurred
in the vbase allocation loop.  This is corrected by updating the error
path for the allocation loop to err4.

Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-06-08 22:38:40 -04:00
Michael S. Tsirkin 8c9bb608e8 ntb: Drop pci_msi_off() call during probe
The PCI core now disables MSI and MSI-X for all devices during enumeration
regardless of CONFIG_PCI_MSI.  Remove device-specific code to disable
MSI/MSI-X.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-07 09:52:22 -05:00
Dave Jiang ab760a0c56 ntb: Adding split BAR support for Haswell platforms
On the Haswell platform, a split BAR option to allow creation of 2
32bit BARs (4 and 5) from the 64bit BAR 4. Adding support for this
new option.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2014-10-17 07:08:51 -04:00
Dave Jiang 069684e888 ntb: use errata flag set via DID to implement workaround
Instead of using a module parameter, we should detect the errata via
PCI DID and then set an appropriate flag. This will be used for additional
errata later on.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2014-10-17 07:08:51 -04:00
Dave Jiang 1db97f2589 ntb: conslidate reading of PPD to move platform detection earlier
To simplify some of the platform detection code. Move the platform detection
to a function to be called earlier.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2014-10-17 07:08:50 -04:00
Dave Jiang b775e85bdb ntb: move platform detection to separate function
Move the platform detection function to separate functions to allow
easier maintenence.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2014-10-17 07:08:50 -04:00
Jon Mason 6465d02ee1 NTB: debugfs device entry
Create a debugfs entry for the NTB device to log the basic device info,
as well as display the error count on a number of registers.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-10-17 07:08:50 -04:00
Dave Jiang 3cc5ba1938 ntb: Add alignment check to meet hardware requirement
The NTB translate register must have the value to be BAR size aligned.
This alignment check make sure that the DMA memory allocated has the
proper alignment. Another requirement for NTB to function properly with
memory window BAR size greater or equal to 4M is to use the CMA feature
in 3.16 kernel with the appropriate CONFIG_CMA_ALIGNMENT and
CONFIG_CMA_SIZE_MBYTES set.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2014-09-14 00:10:38 -04:00
Jon Mason a1413cfbcb NTB: correct the spread of queues over mw's
The detection of an uneven number of queues on the given memory windows
was not correct.  The mw_num is zero based and the mod should be
division to spread them evenly over the mw's.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-09-14 00:10:38 -04:00
Alexander Gordeev f220baad08 ntb: Use pci_enable_msix_range() instead of pci_enable_msix()
As result of deprecation of MSI-X/MSI enablement functions
pci_enable_msix() and pci_enable_msi_block() all drivers
using these two interfaces need to be updated to use the
new pci_enable_msi_range()  or pci_enable_msi_exact()
and pci_enable_msix_range() or pci_enable_msix_exact()
interfaces.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07 10:59:20 -07:00
Alexander Gordeev 53a788a765 ntb: Split ntb_setup_msix() into separate BWD/SNB routines
This is an cleanup effort to make ntb_setup_msix() more
readable - use ntb_setup_bwd_msix() to init MSI-Xs on
BWD hardware and ntb_setup_snb_msix() - on SNB hardware.

Function ntb_setup_snb_msix() also initializes MSI-Xs the
way it should has been done - looping pci_enable_msix()
until success or failure.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07 10:59:19 -07:00
Alexander Gordeev 77733513c4 ntb: Use pci_msix_vec_count() to obtain number of MSI-Xs
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07 10:59:19 -07:00
Jon Mason 53ca4fea0b NTB: Code Style Clean-up
Some white space and 80 char overruns corrected.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07 10:59:19 -07:00
Jon Mason 403c63cb6d NTB: client event cleanup
Provide a better event interface between the client and transport

Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07 10:59:19 -07:00
Alexander Gordeev 717e8e8bfe ntb: Fix leakage of ntb_device::msix_entries[] array
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07 10:58:14 -07:00
Roland Dreier c8eee3795d NTB: Fix typo in setting one translation register
In the code for Xeon devices in back-to-back mode with xeon_errata_workaround
disabled, the downstream device puts the wrong value in SNB_B2B_XLAT_OFFSETL
(SNB_MBAR01_DSD_ADDR vs. SNB_MBAR01_USD_ADDR).

This was spotted while reading code, since the typo has no practical effect,
at least for now: the low 32 bits of both constants are actually identical
anyway.  However, it's clearer and safer to use the right name.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07 10:58:14 -07:00
Linus Torvalds b95485143b NTB driver bug fixes to address a missed call to pci_enable_msix,
NTB-RP Link Up issue, Xeon Doorbell errata workaround, ntb_transport
 link down race, and correct dmaengine_get/put usage.  Also, clean-ups
 to remove duplicate defines and document a hardware errata.  Finally,
 some changes to improve performance.
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Merge tag 'ntb-3.13' of git://github.com/jonmason/ntb

Pull non-transparent bridge updates from Jon Mason:
 "NTB driver bug fixes to address a missed call to pci_enable_msix,
  NTB-RP Link Up issue, Xeon Doorbell errata workaround, ntb_transport
  link down race, and correct dmaengine_get/put usage.

  Also, clean-ups to remove duplicate defines and document a hardware
  errata.  Finally, some changes to improve performance"

* tag 'ntb-3.13' of git://github.com/jonmason/ntb:
  NTB: Disable interrupts and poll under high load
  NTB: Enable Snoop on Primary Side
  NTB: Document HW errata
  NTB: remove duplicate defines
  NTB: correct dmaengine_get/put usage
  NTB: Fix ntb_transport link down race
  ntb: Fix missed call to pci_enable_msix()
  NTB: Fix NTB-RP Link Up
  NTB: Xeon Doorbell errata workaround
2013-11-26 11:15:12 -08:00
Jon Mason e8aeb60c38 NTB: Disable interrupts and poll under high load
Disable interrupts and poll under high load

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:34 -07:00
Jon Mason 78958433db NTB: Enable Snoop on Primary Side
Enable Snoop from Primary to Secondary side on BAR23 and BAR45 on all
TLPs.  Previously, Snoop was only enabled from Secondary to Primary
side.  This can have a performance improvement on some workloads.

Also, make the code more obvious about how the link is being enabled.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:33 -07:00
Jon Mason 58b889206e NTB: Document HW errata
Add a comment describing the necessary ordering of modifications to the
NTB Limit and Base registers.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:33 -07:00
Michael Opdenacker dcf81964e1 NTB: remove duplicate defines
Remove duplicate defines in drivers/ntb/ntb_regs.h

Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:33 -07:00
Jon Mason 94681194e6 NTB: correct dmaengine_get/put usage
dmaengine_get() causes the initialization of the per-cpu channel tables.
It needs to be called prior to dma_find_channel().

Initial version by Dan Williams <dan.j.williams@intel.com>

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:32 -07:00
Jon Mason fca4d5188c NTB: Fix ntb_transport link down race
A WARN_ON is being hit in ntb_qp_link_work due to the NTB transport link
being down while the ntb qp link is still active.  This is caused by the
transport link being brought down prior to the qp link worker thread
being terminated.  To correct this, shutdown the qp's prior to bringing
the transport link down.  Also, only call the qp worker thread if it is
in interrupt context, otherwise call the function directly.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:32 -07:00
Alexander Gordeev 9739047380 ntb: Fix missed call to pci_enable_msix()
Current MSI-X enablement code assumes MSI-Xs were successfully
allocated in case less than requested vectors were available.
That assumption is wrong, since MSI-Xs should be enabled with
a repeated call to pci_enable_msix(). This update fixes this.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:31 -07:00
Jon Mason 9fec60c414 NTB: Fix NTB-RP Link Up
The Xeon NTB-RP setup, the transparent side does not get a link up/down
interrupt.  Since the presence of a NTB device on the transparent side
means that we have a NTB link up, we can work around the lack of an
interrupt by simply calling the link up function to notify the upper
layers.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:31 -07:00
Jon Mason c529aa3033 NTB: Xeon Doorbell errata workaround
Modifications to the 14th bit of the B2BDOORBELL register will not be
mirrored to the remote system due to a hardware issue.  To get around
the issue, shrink the number of available doorbell bits by 1.  The max
number of doorbells was being used as a way to referencing the Link
Doorbell bit.  Since this would no longer work, the driver must now
explicitly reference that bit.

This does not affect the xeon_errata_workaround case, as it is not using
the b2bdoorbell register.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20 09:57:30 -07:00
Bartlomiej Zolnierkiewicz 0776ae7b89 dmaengine: remove DMA unmap flags
Remove no longer needed DMA unmap flags:
- DMA_COMPL_SKIP_SRC_UNMAP
- DMA_COMPL_SKIP_DEST_UNMAP
- DMA_COMPL_SRC_UNMAP_SINGLE
- DMA_COMPL_DEST_UNMAP_SINGLE

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Jon Mason <jon.mason@intel.com>
Acked-by: Mark Brown <broonie@linaro.org>
[djbw: clean up straggling skip unmap flags in ntb]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2013-11-14 11:04:38 -08:00
Bartlomiej Zolnierkiewicz 6f57fd0578 NTB: convert to dmaengine_unmap_data
Use the generic unmap object to unmap dma buffers.

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Jon Mason <jon.mason@intel.com>
[djbw: fix up unmap len, and GFP flags]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2013-11-14 11:01:32 -08:00
Yijing Wang 73f47cadfe ntb: clean up unnecessary MSI/MSI-X capability find
PCI core will initialize device MSI/MSI-X capability in
pci_msi_init_pci_dev(). So device driver should use
pci_dev->msi_cap/msix_cap to determine whether the device
support MSI/MSI-X instead of using
pci_find_capability(pci_dev, PCI_CAP_ID_MSI/MSIX).
Access to PCIe device config space again will consume more time.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05 11:08:01 -07:00
Jon Mason db3bb3f07e NTB: Update Version
Update NTB version to 1.0

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05 11:08:00 -07:00
Jon Mason f9a2cf890b NTB: Comment Fix
Add "data" ntb_register_db_callback parameter description comment and
correct poor spelling.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05 11:08:00 -07:00
Jon Mason 3daa3a073e NTB: Remove unused variable
Remove unused pci_dev variable from ntb_transport_free()

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05 11:07:59 -07:00
Jon Mason b1ef004303 NTB: Remove References of non-B2B BWD HW
NTB-RP is not a supported configuration on BWD hardware.  Remove the
code attempting to set it up.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05 11:07:59 -07:00
Jon Mason ed6c24eda9 NTB: NTB-RP support
Add support for Non-Transparent Bridge connected to a PCI-E Root Port on
the remote system (also known as NTB-RP mode).  This allows for a NTB
enabled system to be connected to a non-NTB enabled system/slot.

Modifications to the registers and BARs/MWs on the Secondary side by the
remote system are reflected into registers on the Primary side for the
local system.  Similarly, modifications of registers and BARs/MWs on
Primary side by the local system are reflected into registers on the
Secondary side for the Remote System.  This allows communication between
the 2 sides via these registers and BARs/MWs.

Note: there is not a fix for the Xeon Errata (that was already worked
around in NTB-B2B mode) for NTB-RP mode.  Due to this limitation, NTB-RP
will not work on the Secondary side with the Xeon Errata workaround
enabled.  To get around this, disable the workaround via the
xeon_errata_workaround=0 modparm.  However, this can cause the hang
described in the errata.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05 11:07:58 -07:00
Jon Mason 497938890a NTB: Rename Variables for NTB-RP
Many variable names in the NTB driver refer to the primary or secondary
side.  However, these variables will be used to access the reverse case
when in NTB-RP mode.  Make these names more generic in anticipation of
NTB-RP support.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05 11:07:58 -07:00
Jon Mason 282a2feeb9 NTB: Use DMA Engine to Transmit and Receive
Allocate and use a DMA engine channel to transmit and receive data over
NTB.  If none is allocated, fall back to using the CPU to transfer data.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
2013-09-05 11:04:09 -07:00
Jon Mason ac477afb04 NTB: Enable 32bit Support
Correct the issues on NTB that prevented it from working on x86_32 and
modify the Kconfig to allow it to be permitted to be used in that
environment as well.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03 14:48:53 -07:00
Jon Mason be4dac0fca NTB: Update Device IDs
Add support for new Intel NTB devices on upcoming Xeon hardware.  Since
the Xeon hardware design is already in place in the driver, all that is
needed are the new device ids.

Remove the device IDs for NTB devs running in Transparent Bridge mode,
as this driver is not being used for those devices.

Rename the device IDs for NTB devs running in NTB-RP mode to better
identify their usage model.  "PS" to denote the Primary Side of NTB, and
"SS" to denote the secondary side.  The primary side is the interface
exposed to the local system, and the secondary side is the interface
exposed to the remote system.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03 14:48:53 -07:00
Jon Mason 113bf1c9f1 NTB: BWD Link Recovery
The BWD NTB device will drop the link if an error is encountered on the
point-to-point PCI bridge.  The link will stay down until all errors are
cleared and the link is re-established.  On link down, check to see if
the error is detected, if so do the necessary housekeeping to try and
recover from the error and reestablish the link.

There is a potential race between the 2 NTB devices recovering at the
same time.  If the times are synchronized, the link will not recover and the
driver will be stuck in this loop forever.  Add a random interval to the
recovery time to prevent this race.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03 14:48:52 -07:00
Jon Mason 948d3a65b6 NTB: Xeon Errata Workaround
There is a Xeon hardware errata related to writes to SDOORBELL or
B2BDOORBELL in conjunction with inbound access to NTB MMIO Space, which
may hang the system.  To workaround this issue, use one of the memory
windows to access the interrupt and scratch pad registers on the remote
system.  This bypasses the issue, but removes one of the memory windows
from use by the transport.  This reduction of MWs necessitates adding
some logic to determine the number of available MWs.

Since some NTB usage methodologies may have unidirectional traffic, the
ability to disable the workaround via modparm has been added.

See BF113 in
http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/xeon-c5500-c3500-spec-update.pdf
See BT119 in
http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/xeon-e5-family-spec-update.pdf

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03 13:51:51 -07:00
Jon Mason 1517a3f21a NTB: Correct debugfs to work with more than 1 NTB Device
Debugfs was setup in NTB to only have a single debugfs directory.  This
resulted in the leaking of debugfs directories and files when multiple
NTB devices were present, due to each device stomping on the variables
containing the previous device's values (thus preventing them from being
freed on cleanup).  Correct this by creating a secondary directory of
the PCI BDF for each device present, and nesting the previously existing
information in those directories.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03 11:14:54 -07:00
Jon Mason b6750cfe07 NTB: Correct USD/DSD Identification
Due to ambiguous documentation, the USD/DSD identification is backward
when compared to the setting in BIOS.  Correct the bits to match the
BIOS setting.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03 11:13:14 -07:00
Jon Mason 8703451151 NTB: Correct Number of Scratch Pad Registers
The NTB Xeon hardware has 16 scratch pad registers and 16 back-to-back
scratch pad registers.  Correct the #define to represent this and update
the variable names to reflect their usage.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03 11:13:13 -07:00
Jon Mason 3b12a0d15b NTB: Add Error Handling in ntb_device_setup
If an error is encountered in ntb_device_setup, it is possible that the
spci_cmd isn't populated.  Writes to the offset can result in a NULL
pointer dereference.  This issue is easily encountered by running in
NTB-RP mode, as it currently is not supported and will generate an
error.  To get around this issue, return if an error is encountered
prior to attempting to write to the spci_cmd offset.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03 11:13:12 -07:00
Jon Mason 8b19d450ad
NTB: Multiple NTB client fix
Fix issue with adding multiple ntb client devices to the ntb virtual
bus.  Previously, multiple devices would be added with the same name,
resulting in crashes.  To get around this issue, add a unique number to
the device when it is added.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:58:22 -07:00
Jon Mason c336acd333
NTB: memcpy lockup workaround
The system will appear to lockup for long periods of time due to the NTB
driver spending too much time in memcpy.  Avoid this by reducing the
number of packets that can be serviced on a given interrupt.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:58:06 -07:00
Jon Mason c9d534c8cb
NTB: Correctly handle receive buffers of the minimal size
The ring logic of the NTB receive buffer/transmit memory window requires
there to be at least 2 payload sized allotments.  For the minimal size
case, split the buffer into two and set the transport_mtu to the
appropriate size.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:57:59 -07:00
Jon Mason 90f9e93464
NTB: reset tx_index on link toggle
If the NTB link toggles, the driver could stop receiving due to the
tx_index not being set to 0 on the transmitting size on a link-up event.
This is due to the driver expecting the incoming data to start at the
beginning of the receive buffer and not at a random place.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:57:51 -07:00
Jon Mason b77b2637b3
NTB: Link toggle memory leak
Each link-up will allocate a new NTB receive buffer when the NTB
properties are negotiated with the remote system.  These allocations did
not check for existing buffers and thus did not free them.  Now, the
driver will check for an existing buffer and free it if not of the
correct size, before trying to alloc a new one.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:57:45 -07:00
Jon Mason 113fc505b8
NTB: Handle 64bit BAR sizes
64bit BAR sizes are permissible with an NTB device.  To support them
various modifications and clean-ups were required, most significantly
using 2 32bit scratch pad registers for each BAR.

Also, modify the driver to allow more than 2 Memory Windows.

Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:57:40 -07:00
Dan Carpenter cc0f868d8a
NTB: fix pointer math issues
->remote_rx_info and ->rx_info are struct ntb_rx_info pointers.  If we
add sizeof(struct ntb_rx_info) then it goes too far.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:57:29 -07:00
Dan Carpenter ad3e2751e7
ntb: off by one sanity checks
These tests are off by one.  If "mw" is equal to NTB_NUM_MW then we
would go beyond the end of the ndev->mw[] array.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:57:24 -07:00
Jon Mason 186f27ff9f
NTB: variable dereferenced before check
Correct instances of variable dereferencing before checking its value on
the functions exported to the client drivers.  Also, add sanity checks
for all exported functions.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15 10:57:17 -07:00
Jon Mason 74465645cd NTB: Fix Sparse Warnings
Address the sparse warnings and resulting fallout

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-21 14:34:21 -08:00
Jon Mason 719234f944 NTB: disable x86_32 support
Atomic readq and writeq do not exist by default on some 32bit
architectures, thus causing compile errors due to non-existent symbols.
Since NTB has not been tested 32bit, disable x86_32 support until such
time as this and any other issues can be properly discovered.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-21 14:34:21 -08:00
Jon Mason 50228c5505 NTB: Update Version
Update NTB version to 0.25

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:48:13 -08:00
Jon Mason 448c6fb3a3 NTB: Out of free receive entries issue
If the NTB client driver enqueues the maximum number of rx buffers, it
will not be able to re-enqueue another in its callback handler due to a
lack of free entries.  This can be avoided by adding the current entry
to the free queue prior to calling the client callback handler.  With
this change, ntb_netdev will no longer encounter a rx error on its first
packet.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:52 -08:00
Jon Mason 793c20e9c9 NTB: Remove reads across NTB
CPU reads across NTB are slow(er) and can hang the local system if an
ECC error is encountered on the remote.  To work around the need for a
read, have the remote side write its current position in the rx buffer
to the local system's buffer and use that to see if there is room when
transmitting.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:51 -08:00
Jon Mason d7237e22bb NTB: correct stack usage warning in debugfs_read
Correct gcc warning of using too much stack debugfs_read.  This is done
by kmallocing the buffer instead of using the char array on stack.
Also, shrinking the buffer to something closer to what is currently
being used.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:51 -08:00
Jon Mason f766755c30 NTB: whitespace cleanups
Whitespace cleanups found via `indent`

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:51 -08:00
Jon Mason 170d35a57c NTB: namespacecheck cleanups
Declare ntb_bus_type static to remove it from name space, and remove
unused ntb_get_max_spads function.  Found via `make namespacecheck`.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:51 -08:00
Jon Mason d66d7ac2e0 NTB: use simple_open for debugfs
Use simple_open for debugfs instead of recreating it in the NTB driver.
Caught by coccicheck.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:51 -08:00
Jon Mason 7b4f2d3c3b NTB: No sleeping in interrupt context
Move all cancel_delayed_work_sync to a work thread to prevent sleeping
in interrupt context (when the NTB link goes down).  Caught via
'Sleep inside atomic section checking'

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:51 -08:00
Jon Mason ef114ed506 NTB: separate transmit and receive windows
Since it is possible for the memory windows on the two NTB connected
systems to be different sizes, the divergent sizes must be accounted for
in the segmentation of the MW's on each side.  Create separate size
variables and initialization as necessary.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:50 -08:00
Jon Mason 842c1ddea5 NTB: correct memory barrier
mmiowb is not sufficient to flush the data and is causing data
corruption.  Change to wmb and the data corruption is no more.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:50 -08:00
Jon Mason 8222b402e2 NTB: Handle ntb client device probes without present hardware
Attempts to probe client ntb drivers without ntb hardware present will
result in null pointer dereference due to the lack of the ntb bus device
being registers.  Check to see if this is the case, and fail all calls
by the clients registering their drivers.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20 15:45:50 -08:00
Greg Kroah-Hartman 78a61ab79a ntb: remove __dev* markings
These are now gone from the kernel, so remove them from the newly-added
drivers before they start to cause build errors for people.

Cc: Jon Mason <jon.mason@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17 19:17:42 -08:00
Jon Mason fce8a7bb5b PCI-Express Non-Transparent Bridge Support
A PCI-Express non-transparent bridge (NTB) is a point-to-point PCIe bus
connecting 2 systems, providing electrical isolation between the two subsystems.
A non-transparent bridge is functionally similar to a transparent bridge except
that both sides of the bridge have their own independent address domains.  The
host on one side of the bridge will not have the visibility of the complete
memory or I/O space on the other side of the bridge.  To communicate across the
non-transparent bridge, each NTB endpoint has one (or more) apertures exposed to
the local system.  Writes to these apertures are mirrored to memory on the
remote system.  Communications can also occur through the use of doorbell
registers that initiate interrupts to the alternate domain, and scratch-pad
registers accessible from both sides.

The NTB device driver is needed to configure these memory windows, doorbell, and
scratch-pad registers as well as use them in such a way as they can be turned
into a viable communication channel to the remote system.  ntb_hw.[ch]
determines the usage model (NTB to NTB or NTB to Root Port) and abstracts away
the underlying hardware to provide access and a common interface to the doorbell
registers, scratch pads, and memory windows.  These hardware interfaces are
exported so that other, non-mainlined kernel drivers can access these.
ntb_transport.[ch] also uses the exported interfaces in ntb_hw.[ch] to setup a
communication channel(s) and provide a reliable way of transferring data from
one side to the other, which it then exports so that "client" drivers can access
them.  These client drivers are used to provide a standard kernel interface
(i.e., Ethernet device) to NTB, such that Linux can transfer data from one
system to the other in a standard way.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17 19:11:14 -08:00