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35 Commits (bec5545edef658f81cd9721dbe8fbebeb3c7534d)

Author SHA1 Message Date
Linus Torvalds bec5545ede New feature to add support for NTB virtual MSI interrupts, the ability
to test and use this feature in the NTB transport layer.  Also, bug
 fixes for the AMD and Switchtec drivers, as well as some general
 patches.
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Merge tag 'ntb-5.3' of git://github.com/jonmason/ntb

Pull NTB updates from Jon Mason:
 "New feature to add support for NTB virtual MSI interrupts, the ability
  to test and use this feature in the NTB transport layer.

  Also, bug fixes for the AMD and Switchtec drivers, as well as some
  general patches"

* tag 'ntb-5.3' of git://github.com/jonmason/ntb: (22 commits)
  NTB: Describe the ntb_msi_test client in the documentation.
  NTB: Add MSI interrupt support to ntb_transport
  NTB: Add ntb_msi_test support to ntb_test
  NTB: Introduce NTB MSI Test Client
  NTB: Introduce MSI library
  NTB: Rename ntb.c to support multiple source files in the module
  NTB: Introduce functions to calculate multi-port resource index
  NTB: Introduce helper functions to calculate logical port number
  PCI/switchtec: Add module parameter to request more interrupts
  PCI/MSI: Support allocating virtual MSI interrupts
  ntb_hw_switchtec: Fix setup MW with failure bug
  ntb_hw_switchtec: Skip unnecessary re-setup of shared memory window for crosslink case
  ntb_hw_switchtec: Remove redundant steps of switchtec_ntb_reinit_peer() function
  NTB: correct ntb_dev_ops and ntb_dev comment typos
  NTB: amd: Silence shift wrapping warning in amd_ntb_db_vector_mask()
  ntb_hw_switchtec: potential shift wrapping bug in switchtec_ntb_init_sndev()
  NTB: ntb_transport: Ensure qp->tx_mw_dma_addr is initaliazed
  NTB: ntb_hw_amd: set peer limit register
  NTB: ntb_perf: Clear stale values in doorbell and command SPAD register
  NTB: ntb_perf: Disable NTB link after clearing peer XLAT registers
  ...
2019-07-21 09:46:59 -07:00
Joey Zhang a944ccc3b0 ntb_hw_switchtec: Fix setup MW with failure bug
Switchtec does not support setting multiple MWs simultaneously. The
driver takes a hardware lock to ensure that two peers are not doing this
simultaneously and it fails if someone else takes the lock. In most
cases, this is fine as clients only setup the MWs once on one side of
the link.

However, there's a race condition when a re-initialization is caused by
a link event. The driver will re-setup the shared memory window
asynchronously and this races with the client setting up it's memory
windows on the link up event.

To fix this we ensure do the entire initialization in a work queue and
signal the client once it's done.

Signed-off-by: Joey Zhang <joey.zhang@microchip.com>
Signed-off-by: Wesley Sheng <wesley.sheng@microchip.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2019-06-13 08:59:31 -04:00
Wesley Sheng f0f43e766b ntb_hw_switchtec: Skip unnecessary re-setup of shared memory window for crosslink case
In case of NTB crosslink topology, the setting of shared memory window in
the virtual partition doesn't reset on peer's reboot. So skip the
unnecessary re-setup of shared memory window for that case.

Signed-off-by: Wesley Sheng <wesley.sheng@microchip.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2019-06-13 08:59:28 -04:00
Joey Zhang 28e339f100 ntb_hw_switchtec: Remove redundant steps of switchtec_ntb_reinit_peer() function
When a re-initialization is caused by a link event, the driver will
re-setup the shared memory window. But at that time, the shared memory
is still valid, and it's unnecessary to free, reallocate and then
initialize it again. We only need to reconfigure the hardware
registers. Remove the redundant steps from
switchtec_ntb_reinit_peer() function.

Signed-off-by: Joey Zhang <joey.zhang@microchip.com>
Signed-off-by: Wesley Sheng <wesley.sheng@microchip.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2019-06-13 08:59:25 -04:00
Dan Carpenter ff148d8ac5 ntb_hw_switchtec: potential shift wrapping bug in switchtec_ntb_init_sndev()
This code triggers a Smatch warning:

    drivers/ntb/hw/mscc/ntb_hw_switchtec.c:884 switchtec_ntb_init_sndev()
    warn: should '(1 << sndev->peer_partition)' be a 64 bit type?

The "part_map" and "tpart_vec" variables are u64 type so this seems like
a valid warning.

Fixes: 3df54c870f ("ntb_hw_switchtec: Allow using Switchtec NTB in multi-partition setups")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2019-06-13 08:59:14 -04:00
Thomas Gleixner 2025cf9e19 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms and conditions of the gnu general public license
  version 2 as published by the free software foundation this program
  is distributed in the hope it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 263 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00
Linus Torvalds e8a71a3866 Fixes for switchtec debugability and mapping table entries, NTB
transport improvements, and a reworking of the peer_db_addr to all for
 better abstraction
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Merge tag 'ntb-5.1' of git://github.com/jonmason/ntb

Pull NTB updates from Jon Mason:

 - fixes for switchtec debugability and mapping table entries

 - NTB transport improvements

 - a reworking of the peer_db_addr for better abstraction

* tag 'ntb-5.1' of git://github.com/jonmason/ntb:
  NTB: add new parameter to peer_db_addr() db_bit and db_data
  NTB: ntb_transport: Ensure the destination buffer is mapped for TX DMA
  NTB: ntb_transport: Free MWs in ntb_transport_link_cleanup()
  ntb_hw_switchtec: Added support of >=4G memory windows
  ntb_hw_switchtec: NT req id mapping table register entry number should be 512
  ntb_hw_switchtec: debug print 64bit aligned crosslink BAR Numbers
2019-03-15 14:32:59 -07:00
Leonid Ravich ebb09b33c6 NTB: add new parameter to peer_db_addr() db_bit and db_data
NTB door bell usage depends on NTB hardware.

ex: intel NTB gen1 has one peer door bell register which can be controlled
by the bitmap writen to it, while Intel NTB gen3 has a registers
per door bell and the data trigering the each door bell is always 1.

therefore exposing only peer door bell address forcing the user
to be aware of such low level details

Signed-off-by: Leonid Ravich <Leonid.Ravich@emc.com>
Acked-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Allen Hubbe <allenbh@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2019-02-13 11:03:18 -05:00
Paul Selles a2585cdc9e ntb_hw_switchtec: Added support of >=4G memory windows
Current Switchtec's BAR setup registers are limited to 32bits,
corresponding to the maximum MW (memory window) size is <4G.

Increase the MW sizes with the addition of the BAR Setup Extension
Register for the upper 32bits of a 64bits MW size. This increases the MW
range to between 4K and 2^63.

Reported-by: Boris Glimcher <boris.glimcher@emc.com>
Signed-off-by: Paul Selles <paul.selles@microchip.com>
Signed-off-by: Wesley Sheng <wesley.sheng@microchip.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2019-02-11 07:36:13 -05:00
Paul Selles cce8e04cf7 ntb_hw_switchtec: debug print 64bit aligned crosslink BAR Numbers
Switchtec NTB crosslink BARs are 64bit addressed but they are printed as
32bit addressed BARs. Fix debug log to increment the BAR numbers by 2 to
reflect the 64bit address alignment.

Fixes: 0175250182 ("ntb_hw_switchtec: Add initialization code for crosslink")
Signed-off-by: Paul Selles <paul.selles@microchip.com>
Signed-off-by: Wesley Sheng <wesley.sheng@microchip.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2019-02-11 07:36:13 -05:00
Greg Kroah-Hartman fdddcfd9c9 Merge 5.0-rc4 into char-misc-next
We need the char-misc fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-28 08:13:52 +01:00
Logan Gunthorpe 8fdf906265 ntb: ntb_hw_switchtec: Cleanup 64bit IO defines to use the common header
Clean up the ifdefs which conditionally defined the io{read|write}64
functions in favour of the new common io-64-nonatomic-lo-hi header.

Per a nit from Andy Shevchenko, the include list is also made
alphabetical.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Jon Mason <jdmason@kudzu.us>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22 13:40:00 +01:00
Luis Chamberlain 750afb08ca cross-tree: phase out dma_zalloc_coherent()
We already need to zero out memory for dma_alloc_coherent(), as such
using dma_zalloc_coherent() is superflous. Phase it out.

This change was generated with the following Coccinelle SmPL patch:

@ replace_dma_zalloc_coherent @
expression dev, size, data, handle, flags;
@@

-dma_zalloc_coherent(dev, size, handle, flags)
+dma_alloc_coherent(dev, size, handle, flags)

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
[hch: re-ran the script on the latest tree]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-08 07:58:37 -05:00
Doug Meyer cfdfc14e7f switchtec: Use generic PCI Vendor ID and Class Code
Move the Microsemi Switchtec PCI Vendor ID (same as
PCI_VENDOR_ID_PMC_Sierra) to pci_ids.h.   Also, replace Microsemi class
constants with the standard PCI definitions.

Signed-off-by: Doug Meyer <dmeyer@gigaio.com>
[bhelgaas: restore SPDX (I assume it was removed by mistake), remove
device ID definitions]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2018-06-29 20:16:44 -05:00
Wei Yongjun ae07abdb84 ntb_hw_switchtec: Make function switchtec_ntb_remove() static
Fixes the following sparse warnings:

drivers/ntb/hw/mscc/ntb_hw_switchtec.c:1552:6: warning:
 symbol 'switchtec_ntb_remove' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:24 -05:00
Arnd Bergmann c6fad21a8d ntb_hw_switchtec: fix logic error
Newer gcc (version 7 and 8 presumably) warn about a statement mixing
the << operator with logical and:

drivers/ntb/hw/mscc/ntb_hw_switchtec.c: In function 'switchtec_ntb_init_sndev':
drivers/ntb/hw/mscc/ntb_hw_switchtec.c:888:24: error: '<<' in boolean context, did you mean '<' ? [-Werror=int-in-bool-context]

My interpretation here is that the author must have intended a bitmask
rather than a comparison, so I'm changing the '&&' to '&', which makes
a lot more sense in the context.

Fixes: 1b249475275d ("ntb_hw_switchtec: Allow using Switchtec NTB in multi-partition setups")
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe 1e2fd202f8 ntb_hw_switchtec: Check for alignment of the buffer in mw_set_trans()
With Switchtec hardware, the buffer used for a memory window must be
aligned to its size (the hardware only replaces the lower bits). In
certain circumstances dma_alloc_coherent() will not provide a buffer
that adheres to this requirement like when using the CMA and
CONFIG_CMA_ALIGNMENT is set lower than the buffer size.

When we get an unaligned buffer mw_set_trans() should return an error.
We also log an error so we know the cause of the problem.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe d04be142b8 ntb_hw_switchtec: Force down the link before initializing
If one host crashes and soft reboots, the other host may not see a
link down event. Then when the crashed host comes back up, the
surviving host may not know the link was reset and the NTB clients
may not work without being reset.

To solve this, we send a LINK_FORCE_DOWN message to each peer every
time we come up, before we register the NTB device. If a surviving
host still thinks the link is up it will take it down immediately.
In this way, once the crashed host comes up fully, it will send a
regular link up event as per usual and the link will be properly
restarted.

While we are in the area, this also fixes the MSG_LINK_UP message that
was in the link down function that was reported by Doug Meyers.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reported-by: ThanhTuThai <cruisethai@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe 270d32e63c ntb_hw_switchtec: Crosslink doorbells and messages
In a crosslink configuration doorbells and messages largely work the
same but the NTB registers must be accessed through the reserved LUT
window. Also, as a bonus, seeing there are now two independent sets of
NTB links, both partitions can actually use all 60 doorbell registers
instead of them having to be split into two for each partition.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe 0175250182 ntb_hw_switchtec: Add initialization code for crosslink
Crosslink is a feature of the Switchtec switches that is similar to
the B2B mode of other NTB devices. It allows a system to be designed
that is perfectly symmetric with two identical switches that link
two hosts together.

In order for the system to be symmetric, there is an empty host-less
partition between the two switches which the host must enumerate and
assign BAR addresses to. The firmware in the switch manages this
specially so that the BAR addresses on both sides of the empty
partition will be identical despite being in the same partition with
the same address space.

The driver determines whether crosslink is enabled by a flag set in
the NTB partition info registers which are set by the switch's
configuration file.

When crosslink is enabled, a reserved LUT window is setup to point to
the peer's switch's NTB registers and the local MWs are set to forward
to the host-less partition's BARs. (Yes, this hurts my brain too.)
Once this is setup, largely the same NTB infrastructure is used to
communicate between the two hosts.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe bbe35ca5aa ntb_hw_switchtec: Make switchtec_ntb_init_req_id_table() more general
This is a prep patch in order to support the crosslink feature which
will require the driver to setup the requester ID table in another
partition as well as it's own. To aid this, create a helper function
which sets up the requester IDs from an array.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe 12cb203b1b ntb_hw_switchtec: Create helper function to setup reserved LUT MWs
This is a prep patch in order to support the crosslink feature which
will require the driver to use another reserved LUT window. To
simplify this we move the code which sets up the reserved LUT window
into a helper function which will be used by the crosslink
initialization.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe c3585cd870 ntb_hw_switchtec: Keep track of the number of LUT windows used by the driver
This is a prep patch in order to support the crosslink feature which will
require the driver to use another reserved LUT window. To simplify this,
we add some code to track the number of reserved LUT windows in use
instead of assuming this is always 1.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Kelvin Cao 3df54c870f ntb_hw_switchtec: Allow using Switchtec NTB in multi-partition setups
Allow using Switchtec NTB in setups that have more than two partitions.
Note: this does not enable having multi-host communication, it only
allows for a single NTB link between two hosts in a network that might
have more than two.

Use following logic to determine the NT peer partition:

1) If there are 2 partitions, and the target vector is set in
   the Switchtec configuration, use the partition specified in target
   vector.
2) If there are 2 partitions and target vector is unset
   use the only other partition as specified in the NT EP map.
3) If there are more than 2 partitions and target vector is set
   use the other partition specified in target vector.
4) If there are more than 2 partitions and target vector is unset,
   this is invalid and report an error.

Signed-off-by: Kelvin Cao <kelvin.cao@microsemi.com>
[logang@deltatee.com: commit message fleshed out]
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Jon Mason 2dd0f6a64a NTB: switchtec_ntb: Add new line on appropriate printks
Trivial addition of "\n" to the dev_* prints where necessary

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Colin Ian King c5ec8b451a NTB: switchtec_ntb: fix spelling mistake: "peforming" -> "performing"
Trivial fix to spelling mistake in dev_err error message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-By: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Doug Meyer 140eb52277 NTB: ntb_hw_switchtec: Fix peer BAR bug in switchtec_ntb_init_shared_mw
This resolves a bug which may incorrectly configure the peer host's
LUT for shared memory window access. The code was using the local
host's first BAR number, rather than the peer hosts's first BAR
number, to determine what peer NT control register to program.

The bug will cause the Switchtec NTB link to work only if both peers
have the same first NTB BAR configured. In all other configurations,
the link will not come up, failing silently.

When both hosts have the same first BAR, the configuration works only
because the first BAR numbers happent to be the same. When the hosts
do not have the same first BAR, then the LUT translation will not be
configured in the correct peer LUT and will not give the peer the
shared memory window access required for the link to operate.

Signed-off-by: Doug Meyer <dmeyer@gigaio.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Fixes: 678784a44ae8 ("NTB: switchtec_ntb: Initialize hardware for memory windows")
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:22 -05:00
Logan Gunthorpe 87d11e645e NTB: switchtec_ntb: Add memory window support
The Switchtec hardware has two types of memory windows: LUTs and Direct.
The first area in each BAR is for LUT windows and the remaining area is
for the direct region. The total number of LUT entries is set by a
configuration setting in hardware and they all must be the same
size. (This is fixed by switchtec_ntb to be 64K.)

switchtec_ntb enables the LUTs only for the first BAR and enables the
highest power of two possible. Seeing the LUTs are at the beginning of
the BAR, the direct memory window's alignment is affected. Therefore,
the maximum direct memory window size can not be greater than the number
of LUTs times 64K. The direct window in other BARs will not have this
restriction as the LUTs will not be enabled there. LUTs will only be
exposed through the NTB API if the use_lut_mw parameter is set.

Seeing the Switchtec hardware, by default, configures BARs to be 4G a
module parameter is given to limit the size of the advertised memory
windows. Higher layers tend to allocate the maximum BAR size and this
has a tendency to fail when they try to allocate 4GB of contiguous
memory.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-11-18 20:37:12 -05:00
Logan Gunthorpe b9a4acac28 NTB: switchtec_ntb: Implement scratchpad registers
Seeing there is no dedicated hardware for this, we simply add
these as entries in the shared memory window. Thus, we could support
any number of them but 128 seems like enough, for now.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-11-18 20:37:12 -05:00
Logan Gunthorpe 6619bf9549 NTB: switchtec_ntb: Implement doorbell registers
Pretty straightforward implementation of doorbell registers.
The shift and mask were setup in an earlier patch and this just hooks
up the appropriate portion of the IDB register as the local doorbells
and the opposite portion of ODB as the peer doorbells. The DB mask is
protected by a spinlock to avoid concurrent read-modify-write accesses.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-11-18 20:37:12 -05:00
Logan Gunthorpe 0ee28f26f3 NTB: switchtec_ntb: Add link management
switchtec_ntb checks for a link by looking at the shared memory
window. If the magic number is correct and the other side indicates
their link is enabled then we take the link to be up.

Whenever we change our local link status we send a msg to the
other side to check whether it's up and change their status.

The current status is maintained in a flag so ntb_is_link_up
can return quickly.

We utilize Switchtec's link status notifier to also check link changes
when the switch notices a port changes state.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-11-18 20:37:12 -05:00
Logan Gunthorpe e099b45b7c NTB: switchtec_ntb: Add skeleton NTB driver
Add a skeleton NTB driver which will be filled out in subsequent patches.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-11-18 20:37:12 -05:00
Logan Gunthorpe 3dd4db475c NTB: switchtec_ntb: Initialize hardware for doorbells and messages
Set up some hardware registers and creates interrupt service routines
for the doorbells and messages.

There are 64 doorbells in the switch that are shared between all
partitions. The upper 4 doorbells are also shared with the messages
and are therefore not used. Thus, this provides 28 doorbells for each
partition.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-11-18 20:37:12 -05:00
Logan Gunthorpe ec0467ccbd NTB: switchtec_ntb: Initialize hardware for memory windows
Add the code to initialize the memory windows in the hardware.
This includes setting up the requester ID table, and figuring out
which BAR corresponds to which memory window. (Seeing the switch
can be configured with any number of BARs.)

Also, seeing the device doesn't have hardware for scratchpads or
determining the link status, we create a shared memory window that has
these features. A magic number with a version component will be used
to determine if the other side's driver is actually up.

The shared memory window also informs the other side of the
size and count of the local memory windows.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-11-18 20:37:12 -05:00
Logan Gunthorpe 33dea5aae0 NTB: switchtec_ntb: Introduce initial NTB driver
Seeing the Switchtec NTB hardware shares the same endpoint as the
management endpoint we utilize the class_interface API to register
an NTB driver for every Switchtec device in the system that has the
NTB class code.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2017-11-18 20:37:12 -05:00