[efi] Poll for TX completions only when there is an outstanding TX buffer
At least one NII implementation (in a Microsoft Surface tablet) seems
to fail to report the absence (sic) of TX completions properly. Work
around this by checking for TX completions only when we expect to see
one.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Poll media status only if advertised as supported
Some NII implementations will fail the GET_STATUS operation if we
request the media status. Fix by doing so only if GET_INIT_INFO
reported that media status is supported.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[smsc75xx] Move RX FIFO overflow message to DBGLVL_EXTRA
RX FIFO overflow is almost inevitable since the (usable) USB2 bus
bandwidth is approximately one quarter of the Ethernet bandwidth.
Avoid flooding the console with RX FIFO overflow messages in a
standard debug build.
With TCP SACK implemented, the RX FIFO overflow no longer causes a
catastrophic drop in throughput. Experimentation shows that HTTP
downloads now progress at a fairly smooth 250Mbps, which is around the
maximum speed attainable for a USB2 NIC.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[smsc75xx] Add driver for SMSC/Microchip LAN75xx USB Ethernet NICs
This driver is functional but any downloads via a TCP-based protocol
tend to perform poorly. The 1Gbps Ethernet line rate is substantially
higher than the 480Mbps (in practice around 280Mbps) provided by USB2,
and the device has only 32kB of internal buffer memory. Our 256kB TCP
receive window therefore rapidly overflows the RX FIFO, leading to
multiple dropped packets (usually within the same TCP window) and
hence a low overall throughput.
Reducing the TCP window size so that the RX FIFO does not overflow
greatly increases throughput, but is not a general-purpose solution.
Further investigation is required to determine how other OSes
(e.g. Linux) cope with this scenario. It is possible that
implementing TCP SACK would provide some benefit.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Most devices expose at least the link up/down status via a bit in a
MAC register, since the MAC generally already needs to know whether or
not the link is up. Some devices (e.g. the SMSC75xx USB NIC) expose
this information to software only via the MII registers.
Provide a generic mii_check_link() implementation to check the BMSR
and report the link status via netdev_link_{up,down}().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[xen] Set the "feature-rx-notify" flag for netfront devices
iPXE already sends RX notifications to the backend when needed, but
does not set the "feature-rx-notify" flag. As of XenServer 6.5, this
flag is mandatory and omitting it will cause the backend to fail.
Fix by setting the "feature-rx-notify" flag, to inform the backend
that we will send notifications.
Reported-by: Shalom Bhooshi <shalom.bhooshi@citrix.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[legal] Relicense files under GPL2_OR_LATER_OR_UBDL
Relicense files with kind permission from
Stefan Hajnoczi <stefanha@redhat.com>
alongside the contributors who have already granted such relicensing
permission.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
At some point in the past few years, binutils became more aggressive
at removing unused symbols. To function as a symbol requirement, a
relocation record must now be in a section marked with @progbits and
must not be in a section which gets discarded during the link (either
via --gc-sections or via /DISCARD/).
Update REQUIRE_SYMBOL() to generate relocation records meeting these
criteria. To minimise the impact upon the final binary size, we use
existing symbols (specified via the REQUIRING_SYMBOL() macro) as the
relocation targets where possible. We use R_386_NONE or R_X86_64_NONE
relocation types to prevent any actual unwanted relocation taking
place. Where no suitable symbol exists for REQUIRING_SYMBOL() (such
as in config.c), the macro PROVIDE_REQUIRING_SYMBOL() can be used to
generate a one-byte-long symbol to act as the relocation target.
If there are versions of binutils for which this approach fails, then
the fallback will probably involve killing off REQUEST_SYMBOL(),
redefining REQUIRE_SYMBOL() to use the current definition of
REQUEST_SYMBOL(), and postprocessing the linked ELF file with
something along the lines of "nm -u | wc -l" to check that there are
no undefined symbols remaining.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[legal] Include full licence text for all GPL2_OR_LATER files
Add the standard warranty disclaimer and Free Software Foundation
address paragraphs to the licence text where these are not currently
present.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Allow usb_stream() to enforce a terminating short packet
Some USB endpoints require that a short packet be used to terminate
transfers, since they have no other way to determine message
boundaries. If the message length happens to be an exact multiple of
the USB packet size, then this requires the use of an additional
zero-length packet.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some protocols (such as ARP) may modify the received packet and re-use
the same I/O buffer for transmission of a reply. To allow this,
reserve sufficient headroom at the start of each received packet
buffer for our transmit datapath headers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some devices have a very small number of internal buffers, and rely on
being able to pack multiple packets into each buffer. Using 2048-byte
buffers on such devices produces throughput of around 100Mbps. Using
a small number of much larger buffers (e.g. 32kB) increases the
throughput to around 780Mbps. (The full 1Gbps is not reached because
the high RTT induced by the use of multi-packet buffers causes us to
saturate our 256kB TCP window.)
Since allocation of large buffers is very likely to fail, allocate the
buffer set only once when the device is opened and recycle buffers
immediately after use. Received data is now always copied to
per-packet buffers.
If allocation of large buffers fails, fall back to allocating a larger
number of smaller buffers. This will give reduced performance, but
the device will at least still be functional.
Share code between the interrupt and bulk IN endpoint handlers, since
the buffer handling is now very similar.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[hyperv] Assume that VMBus xfer page ranges correspond to RNDIS messages
The (undocumented) VMBus protocol seems to allow for transfer
page-based packets where the data payload is split into an arbitrary
set of ranges within the transfer page set.
The RNDIS protocol includes a length field within the header of each
message, and it is known from observation that multiple RNDIS messages
can be concatenated into a single VMBus message.
iPXE currently assumes that the transfer page range boundaries are
entirely arbitrary, and uses the RNDIS header length to determine the
RNDIS message boundaries.
Windows Server 2012 R2 generates an RNDIS_INDICATE_STATUS_MSG for an
undocumented and unknown status code (0x40020006) with a malformed
RNDIS header length: the length does not cover the StatusBuffer
portion of the message. This causes iPXE to report a malformed RNDIS
message and to discard any further RNDIS messages within the same
VMBus message.
The Linux Hyper-V driver assumes that the transfer page range
boundaries correspond to RNDIS message boundaries, and so does not
notice the malformed length field in the RNDIS header.
Match the behaviour of the Linux Hyper-V driver: assume that the
transfer page range boundaries correspond to the RNDIS message
boundaries and ignore the RNDIS header length. This avoids triggering
the "malformed packet" error and also avoids unnecessary data copying:
since we now have one I/O buffer per RNDIS message, there is no longer
any need to use iob_split().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Empirical observation suggests that 32 is a sensible size to minimise
the number of deferred packet transmissions without overflowing the
VMBus transmit ring buffer.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow for elision of transmitted TCP ACKs by handling all received
VMBus messages in each network device poll operation.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[hyperv] Tear down NetVSC RX buffer GPADL after closing VMBus device
On Windows Server 2012 R2, the receive buffer teardown completion
message seems to occasionally be deferred until after the VMBus
channel has been closed. This happens even if there are no packets
currently in the receive buffer.
Work around this problem by separating the revocation and teardown of
the receive buffer, and deferring the teardown until after the VMBus
channel has been closed.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Use autoloaded MAC address instead of EEPROM MAC address
The i350 (and possibly other Intel NICs) have a non-trivial
correspondence between the PCI function number and the external
physical port number. For example, the i350 has a "LAN Function Sel"
bit within the EEPROM which can invert the mapping so that function 0
becomes port 3, function 1 becomes port 2, etc.
Unfortunately the MAC addresses within the EEPROM are indexed by
physical port number rather than PCI function number. The end result
is that when anything other than the default mapping is used, iPXE
will use the wrong address as the base MAC address.
Fix by using the autoloaded MAC address if it is valid, and falling
back to reading the MAC address directly from the EEPROM only if no
autoloaded address is available.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Include NII driver within "snp" and "snponly" build targets
End users almost certainly don't care whether the underlying interface
is SNP or NII/UNDI. Try to minimise surprise and unnecessary
documentation by including the NII driver whenever the SNP driver is
requested.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE itself exposes a dummy NII protocol with no UNDI. Avoid
potentially dereferencing a NULL pointer by checking for a non-zero
UNDI address.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some UEFI network drivers provide a software UNDI interface which is
exposed via the Network Interface Identifier Protocol (NII), rather
than providing a Simple Network Protocol (SNP).
The UEFI platform firmware will usually include the SnpDxe driver,
which attaches to NII and provides an SNP interface. The SNP
interface is usually provided on the same handle as the underlying NII
device. This causes problems for our EFI driver model: when
efi_driver_connect() detaches existing drivers from the handle it will
cause the SNP interface to be uninstalled, and so our SNP driver will
not be able to attach to the handle. The platform firmware will
eventually reattach the SnpDxe driver and may attach us to the SNP
handle, but we have no way to prevent other drivers from attaching
first.
Fix by providing a driver which can attach directly to the NII
protocol, using the software UNDI interface to drive the network
device.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Free transmit ring entry before calling netdev_tx_complete()
The snpnet driver uses netdev_tx_defer() and so must ensure that space
in the (single-entry) transmit descriptor ring is freed up before
calling netdev_tx_complete().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add the ID for the LM variant and differentiate it from the I217-V.
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We currently require information about the underlying PCI device to
populate the snpnet device's name and description. If the underlying
device is not a PCI device, this will fail and prevent the device from
being registered.
Fix by falling back to populating the device description with
information based on the EFI handle, if no PCI device information is
available.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Use the SNP protocol instance to match the SNP chainloading device
Some systems will install a child of the SNP device and use this as
our loaded image's device handle, duplicating the installation of the
underlying SNP protocol onto the child device handle. On such
systems, we want to end up driving the parent device (and
disconnecting any other drivers, such as MNP, which may be attached to
the parent device).
Fix by recording the SNP protocol instance at initialisation time, and
using this to match against device handles (rather than simply
comparing the handles themselves).
Reported-by: Jarrod Johnson <jarrod.b.johnson@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Apply PBS/PBA errata workaround only to ICH8 PCI device IDs
ICH8 devices have an errata which requires us to reconfigure the
packet buffer size (PBS) register, and correspondingly adjust the
packet buffer allocation (PBA) register. The "Intel I/O Controller
Hub ICH8/9/10 and 82566/82567/82562V Software Developer's Manual"
notes for the PBS register that:
10.4.20 Packet Buffer Size - PBS (01008h; R/W)
Note: The default setting of this register is 20 KB and is
incorrect. This register must be programmed to 16 KB.
Initial value: 0014h
0018h (ICH9/ICH10)
It is unclear from this comment precisely which devices require the
workaround to be applied. We currently attempt to err on the side of
caution: if we detect an initial value of either 0x14 or 0x18 then the
workaround will be applied. If the workaround is applied
unnecessarily, then the effect should be just that we use less than
the full amount of the available packet buffer memory.
Unfortunately this approach does not play nicely with other device
drivers. For example, the Linux e1000e driver will rewrite PBA while
assuming that PBS still contains the default value, which can result
in inconsistent values between the two registers, and a corresponding
inability to transmit or receive packets. Even more unfortunately,
the contents of PBS and PBA are not reset by anything less than a
power cycle, meaning that this error condition will survive a hardware
reset.
The Linux driver (written and maintained by Intel) applies the PBS/PBA
errata workaround only for devices in the ICH8 family, identified via
the PCI device ID. Adopt a similar approach, using the PCI_ROM()
driver data field to indicate when the workaround is required.
Reported-by: Donald Bindner <dbindner@truman.edu>
Debugged-by: Donald Bindner <dbindner@truman.edu>
Signed-off-by: Michael Brown <mcb30@ipxe.org>