Because it can sleep drainking link work callout(s). Linux (dual
BSD/GPL driver) does something very similar.
At the same time, switch the NTB CTX lock to a non-spin mutex, because
the taskqueue_swi lock can't be taken after a spin mutex.
Suggested by: Witness
Sponsored by: EMC / Isilon Storage Division
In ntb_poll_link, we are intentionally writing the link bit, which is
absent from db_valid_mask. Don't panic on a kassert when we do so.
The Linux version of this (dual BSD/GPL) driver has the db_valid_mask
assertions in callers of db_iowrite() rather than db_iowrite() itself;
it skips the assertions in the equivalent of ntb_poll_link(). Rather
than duplicating the assertions in every caller, add a db_iowrite_raw()
that doesn't check and use it from ntb_poll_link().
Suggested by: kassert_panic
Sponsored by: EMC / Isilon Storage Division
AMD64 pmap assumes ranges will be in the DMAP, which isn't necessarily
true for NTB memory windows (especially 64-bit BARs).
Suggested by: pmap_change_attr_locked -> kassert_panic
Sponsored by: EMC / Isilon Storage Division
This should export all of the same information as the Linux ntb_hw_intel
debugfs info file, but with a bit more structure, in the sysctl tree
rooted at 'dev.ntb_hw.<N>.debug_info'.
Raw registers are marked as OPAQUE because reading them on some hardware
revisions may cause a hard lockup (NTB errata). They can be read with
'sysctl -x dev.ntb_hw.<N>.debug_info.registers'. On Xeon platforms,
some additional registers are available under 'registers.xeon_stats' and
'registers.xeon_hw_err'. They are exported as big-endian values so that
the 'sysctl -x' output is legible.
Shrink the feature mask to 32 bits so we can use the %b formatter in
'debug_info.features'.
Sponsored by: EMC / Isilon Storage Division
Add ntb_q_idx_t so it is more clear which struct members are of the same
type (some bogus uint64_ts snuck in that should have been unsigned int).
Add tx_err_no_buf and s/ENOMEM/EBUSY/ in tx_enqueue to match Linux.
Sponsored by: EMC / Isilon Storage Division
A plain 32 bit integer will overflow for values over 4GiB.
Change the plain integer size to the appropriate size type in
ntb_set_mw. Change the type of the size parameter and two local
variables used for size.
Even if there is no overflow, a size of zero is invalid here.
Authored by: Allen Hubbe
Reported by: Juyoung Jung
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
It was possible for a synchronous update of the RX index in the error
case to get ahead of the asynchronous RX index update in the normal
case. Change the RX processing to preserve an RX completion order.
There were two error cases. First, if a buffer is not present to
receive data, there would be no queue entry to preserve the RX
completion order. Instead of dropping the RX frame, leave the RX frame
in the ring. Schedule RX processing when RX entries are enqueued, in
case there are RX frames waiting in the ring to be received.
Second, if a buffer is too small to receive data, drop the frame in the
ring, mark the RX entry as done, and indicate the error in the RX entry
length. Check for a negative length in the receive callback in
ntb_netdev, and count occurrences as rx_length_errors.
Authored by: Allen Hubbe
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Mechanically replace "SOC" with "ATOM" to match Linux. No functional
change. Original Linux commit log follows:
Instead of using the platform code names, use the correct platform names
to identify the respective Intel NTB hardware.
Authored by: Dave Jiang
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Prints driver name to indicate what is being loaded.
Authored by: Dave Jiang
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Benchmarking showed a significant performance increase with the MTU size
to 64k instead of 16k. Change the driver default to 64k.
Authored by: Dave Jiang
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Throw away the result of the peer SPAD read. The peer will write our
local SPAD and we need to keep the locally read SPAD value to check if
the remote side is up.
Sponsored by: EMC / Isilon Storage Division
Add module parameters for the addresses to be used in B2B topology.
Authored by: Allen Hubbe
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Reset the link stats when the link goes down. In particular, the TX and
RX index and count must be reset, or else the TX side will be sending
packets to the RX side where the RX side is not expecting them. Reset
all the stats, to be consistent.
Authored by: Allen Hubbe
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
We skip actually bringing up Rootport/Transparent configurations, so
most of this doesn't apply. Original Linux commit log:
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.
Authored by: Dave Jiang
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
It is just a trivial wrapper around ntb_mw_set_trans().
Authored by: Allen Hubbe
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
This is the last e26a5843 patch. The general thrust of the rewrite was
to move more responsibility for Memory Window and Doorbell interrupt
management from the ntb_hw driver to if_ntb.
A number of APIs have been added, removed, or replaced. The old
DB callback mechanism has been excised. Instead, callers (if_ntb) are
responsible for configuring MWs and handling their interrupts more
directly.
This adds a tunable, hw.ntb.max_mw_size, allowing users to limit the
size of memory windows used by if_ntb (identical to the Linux modparam
of the same name).
Despite attempts to keep mechanical name changes to separate commits,
some have snuck in here. At least the driver should be much more
similar to the latest Linux one now -- making porting fixes easier.
Authored by: Allen Hubbe
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
No functional change. Part of the huge rewrite (e26a5843).
Obtained from: Linux (e26a5843) (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Move all Xeon secondary register setup to the setup_b2b_mw routine. We
use subroutines to make it a bit less wordy than the Linux version.
Adds a new tunable, 'hw.ntb.b2b_mw_share'. By default, it is off
(zero). If both sides enable it (any non-zero value), the NTB driver
attempts to use only half of a memory window for remote register MMIO
access.
This is still part of the large Linux rewrite (e26a5843).
Authored by: Allen Hubbe
Obtained from: Linux (e26a5843) (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
This Linux commit was more or less a rewrite. Unfortunately, the commit
log does not give a lot of context for the rewrite. I have tried to
faithfully follow the changes made upstream, including matching function
names where possible, while churning the FreeBSD driver as little as
possible.
This is the bulk of the rewrite. There are two groups of changes to
follow in separate commits: fleshing out the rest of the changes to
xeon_setup_b2b_mw(), and some changes to if_ntb.
Yes, this is a big patch (3 files changed, 416 insertions(+), 237
deletions(-)), but the Linux patch was 13 files changed, 2,589
additions(+) and 2,195 deletions(-).
Original Linux commit log:
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.
Authored by: Allen Hubbe
Obtained from: Linux (e26a5843) (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Some interrupt-related function names changed to match Linux.
No functional change. Still part of the huge e26a5843 rewrite in Linux.
Obtained from: Linux (e26a5843) (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
No functional change.
Still part of the huge e26a5843 rewrite. I'm trying to make it less of
a complete rewrite in the FreeBSD version of the driver. Still, it
helps if our names match Linux.
Obtained from: Linux (e26a5843) (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Dave Jiang
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
This is a follow-up to r289208: "Xeon Errata Workaround."
Add logic to support a variable number of memory windows and doorbell
callbacks. This was added to the Linux driver in the "Xeon Errata
Workaround" commit, but I skipped it because it didn't look neccessary
at the time. It is needed for future Haswell split-BAR support, so
bring it in now.
A new tunable was added for if_ntb, 'hw.ntb.max_num_clients'. By
default, it is set to zero -- infer the number of clients from the
number of memory windows available from the hardware. Any other
positive value can specify a different number of clients, limited by the
number of doorbell callbacks available (4 under MSI-X, or 15 (Xeon) or
34 (SoC) under legacy INTx).
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Pull out read of PPD and platform detection logic to new functions,
ntb_detect_xeon(), ntb_detect_soc(). No functional change -- mostly
this is just shuffling the code to more closely match the Linux driver.
Linux commit log:
To simplify some of the platform detection code. Move the platform
detection to a function to be called earlier.
Authored by: Dave Jiang
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
The doorbell registers (and associated mask) are 16-bit on Xeon but
64-bit on SoC. Abstract IO access to doorbell registers with
'db_ioread' and 'db_iowrite' (names and idea borrowed from the dual
BSD/GPL Linux driver).
Sponsored by: EMC / Isilon Storage Division
Original Linux commit log:
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.
Authored by: Dave Jiang
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Remap MSI-X messages over available slots rather than falling back to
legacy INTx when fewer MSI-X slots are available than were requested.
N.B. the Linux driver does *not* do this.
To aid in testing, a tunable 'hw.ntb.force_remap_mode' has been added.
It defaults to off (0). When the tunable is enabled and sufficient
slots were available, the driver restricts the number of slots by one
and remaps the MSI-X messages over the remaining slots.
In case this is actually not okay (as I don't yet have access to this
hardware to test), a tunable 'hw.ntb.prefer_intx_to_remap' has been
added. It defaults to off (0). When the tunable is enabled and fewer
slots are available than requested, fall back to legacy INTx mode rather
than attempting to remap MSI-X messages.
Suggested by: jhb
Reviewed by: jhb (earlier version)
Sponsored by: EMC / Isilon Storage Division
Consumers that registered on this bit would never see a callback and it
is likely a mistake.
This does not affect if_ntb, which limits itself to a single doorbell
callback.
The names don't line up 100% with Linux. Our routines are named
ntb_setup_interrupts, ntb_setup_xeon_msix, ntb_setup_soc_msix, and
ntb_setup_legacy_interrupt. Linux SNB = FreeBSD Xeon; Linux BWD =
FreeBSD SOC. Original Linux commit log:
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.
Authored by: Alexander Gordeev
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Provide a better event interface between the client and transport.
Authored by: Jon Mason
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
Add a comment describing the necessary ordering of modifications to the
NTB Limit and Base registers.
Authored by: Jon Mason
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
NTB-RP is not a supported configuration on BWD hardware. Remove the
code attempting to set it up.
Authored by: Jon Mason
Obtained from: Linux (dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division
This commit does not actually add NTB-RP support. Mostly it serves to
shuffle code around to match the Linux driver. Original Linux commit
log follows:
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
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.
Authored by: Jon Mason
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
->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.
Authored by: Dan Carpenter
Obtained from: Linux
Sponsored by: EMC / Isilon Storage Division
years for head. However, it is continuously misused as the mpsafe argument
for callout_init(9). Deprecate the flag and clean up callout_init() calls
to make them more consistent.
Differential Revision: https://reviews.freebsd.org/D2613
Reviewed by: jhb
MFC after: 2 weeks
The NTB allows you to connect two systems with this device using a PCI-e
link. The driver is made of two modules:
- ntb_hw which is a basic hardware abstraction layer for the device.
- if_ntb which implements the ntb network device and the communication
protocol.
The driver is limited at the moment to CPU memcpy instead of using DMA, and
only Back-to-Back mode is supported. Also the network device isn't full
featured yet. These changes will be coming soon. The DMA change will also
bring in the ioat driver from the project branch it is on now.
This is an initial port of the GPL/BSD Linux driver contributed by Jon Mason
from Intel. Any bugs are my contributions.
Sponsored by: Intel
Reviewed by: jimharris, joel (man page only)
Approved by: jimharris (mentor)
