Use the tail register offset (which exists for all ring types) as the
ring identifier in all relevant debug messages.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Commit 8f3e648 ("[intelxl] Use one admin queue buffer per admin queue
descriptor") changed the API for intelxl_admin_command() such that the
caller now constructs the command directly within the next available
descriptor ring entry, rather than relying on intelxl_admin_command()
to copy the descriptor to and from the descriptor ring.
This introduced a regression in intelxl_admin_switch(), since the
second and subsequent iterations of the loop will not have constructed
a valid command in the new descriptor ring entry before calling
intelxl_admin_command().
Fix by constructing the command within the loop.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Include a potential DMA mapping within the definition of an I/O
buffer, and move all I/O buffer DMA mapping functions from dma.h to
iobuf.h. This avoids the need for drivers to maintain a separate list
of DMA mappings for each I/O buffer that they may handle.
Network device drivers typically do not keep track of transmit I/O
buffers, since the network device core already maintains a transmit
queue. Drivers will typically call netdev_tx_complete_next() to
complete a transmission without first obtaining the relevant I/O
buffer pointer (and will rely on the network device core automatically
cancelling any pending transmissions when the device is closed).
To allow this driver design approach to be retained, update the
netdev_tx_complete() family of functions to automatically perform the
DMA unmapping operation if required. For symmetry, also update the
netdev_rx() family of functions to behave the same way.
As a further convenience for drivers, allow the network device core to
automatically perform DMA mapping on the transmit datapath before
calling the driver's transmit() method. This avoids the need to
introduce a mapping error handling code path into the typically
error-free transmit methods.
With these changes, the modifications required to update a typical
network device driver to use the new DMA API are fairly minimal:
- Allocate and free descriptor rings and similar coherent structures
using dma_alloc()/dma_free() rather than malloc_phys()/free_phys()
- Allocate and free receive buffers using alloc_rx_iob()/free_rx_iob()
rather than alloc_iob()/free_iob()
- Calculate DMA addresses using dma() or iob_dma() rather than
virt_to_bus()
- Set a 64-bit DMA mask if needed using dma_set_mask_64bit() and
thereafter eliminate checks on DMA address ranges
- Either record the DMA device in netdev->dma, or call iob_map_tx() as
part of the transmit() method
- Ensure that debug messages use virt_to_phys() when displaying
"hardware" addresses
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Redefine the value stored within a DMA mapping to be the offset
between physical addresses and DMA addresses within the mapped region.
Provide a dma() wrapper function to calculate the DMA address for any
pointer within a mapped region, thereby simplifying the use cases when
a device needs to be given addresses other than the region start
address.
On a platform using the "flat" DMA implementation the DMA offset for
any mapped region is always zero, with the result that dma_map() can
be optimised away completely and dma() reduces to a straightforward
call to virt_to_phys().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
For the physical function driver, the transmit queue needs to be
configured to be associated with the relevant physical function
number. This is currently obtained from the bus:dev.fn address of the
underlying PCI device.
In the case of a virtual machine using the physical function via PCI
passthrough, the PCI bus:dev.fn address within the virtual machine is
unrelated to the real physical function number. Such a function will
typically be presented to the virtual machine as a single-function
device. The function number extracted from the PCI bus:dev.fn address
will therefore always be zero.
Fix by reading from the Function Requester ID Information Register,
which always returns the real PCI bus:dev.fn address as used by the
physical host.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The datasheet is fairly incomprehensible in terms of identifying the
appropriate MAC address for use by the physical function driver.
Choose to read the MAC address from PRTPM_SAH and PRTPM_SAL, which at
least matches the MAC address as selected by the Linux i40e driver.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The malloc_dma() function allocates memory with specified physical
alignment, and is typically (though not exclusively) used to allocate
memory for DMA.
Rename to malloc_phys() to more closely match the functionality, and
to create name space for functions that specifically allocate and map
DMA-capable buffers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The physical function defaults to operating in "PXE mode" after a
power-on reset. In this mode, receive descriptors are fetched and
written back as single descriptors. In normal (non-PXE mode)
operation, receive descriptors are fetched and written back only as
complete cachelines unless an interrupt is raised.
There is no way to return to PXE mode from non-PXE mode, and there is
no way for the virtual function driver to operate in PXE mode.
Choose to operate in non-PXE mode. This requires us to trick the
hardware into believing that it is raising an interrupt, so that it
will not defer writing back receive descriptors until a complete
cacheline (i.e. four packets) have been consumed. We do so by
configuring the hardware to use MSI-X with a dummy target location in
place of the usual APIC register.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The virtual function driver will use the same transmit and receive
descriptor ring structures, but will not itself construct and program
the ring context. Split out ring creation and destruction from the
programming of the ring context, to allow code to be shared between
physical and virtual function drivers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The virtual function transmit and receive ring tail register offsets
do not match those of the physical function. Allow the tail register
offsets to be specified separately.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The physical function driver does not allow the virtual function to
request the use of 16-byte receive descriptors. Switch to using
32-byte receive descriptors.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide a weak stub function for handling the "send to VF" event used
for communications between the physical and virtual function drivers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The "send to PF" and "send to VF" admin queue descriptors (ab)use the
cookie field to hold the extended opcode and return code values.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
A virtual function reset is triggered via an admin queue command and
will reset the admin queue configuration registers. Allow the admin
queues to be reinitialised after such a reset, without requiring the
overhead (and potential failure paths) of freeing and reallocating the
queues.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We currently use a single data buffer shared between all admin queue
descriptors. This works for the physical function driver since we
have at most one command in progress and only a single event (which
does not use a data buffer).
The communication path between the physical and virtual function
drivers uses the event data buffer, and there is no way to prevent a
solicited event (i.e. a response to a request) from being overwritten
by an unsolicited event (e.g. a link status change).
Provide individual data buffers for each admin event queue descriptor
(and for each admin command queue descriptor, for the sake of
consistency).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The register map for the virtual functions appears to have been
constructed using a random number generator.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The physical function driver does not allow the virtual function to
request that VLAN tags are left unstripped. Extract and use the VLAN
tag from the receive descriptor if present.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown