Commit Graph

11 Commits

Author SHA1 Message Date
Vladimir Oltean
e3972399bb net: enetc: build common object files into a separate module
The build system is complaining about the following:

enetc.o is added to multiple modules: fsl-enetc fsl-enetc-vf
enetc_cbdr.o is added to multiple modules: fsl-enetc fsl-enetc-vf
enetc_ethtool.o is added to multiple modules: fsl-enetc fsl-enetc-vf

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-23 13:13:08 +00:00
Vladimir Oltean
5641c751fe net: enetc: deny offload of tc-based TSN features on VF interfaces
TSN features on the ENETC (taprio, cbs, gate, police) are configured
through a mix of command BD ring messages and port registers:
enetc_port_rd(), enetc_port_wr().

Port registers are a region of the ENETC memory map which are only
accessible from the PCIe Physical Function. They are not accessible from
the Virtual Functions.

Moreover, attempting to access these registers crashes the kernel:

$ echo 1 > /sys/bus/pci/devices/0000\:00\:00.0/sriov_numvfs
pci 0000:00:01.0: [1957:ef00] type 00 class 0x020001
fsl_enetc_vf 0000:00:01.0: Adding to iommu group 15
fsl_enetc_vf 0000:00:01.0: enabling device (0000 -> 0002)
fsl_enetc_vf 0000:00:01.0 eno0vf0: renamed from eth0
$ tc qdisc replace dev eno0vf0 root taprio num_tc 8 map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 base-time 0 \
	sched-entry S 0x7f 900000 sched-entry S 0x80 100000 flags 0x2
Unable to handle kernel paging request at virtual address ffff800009551a08
Internal error: Oops: 96000007 [#1] PREEMPT SMP
pc : enetc_setup_tc_taprio+0x170/0x47c
lr : enetc_setup_tc_taprio+0x16c/0x47c
Call trace:
 enetc_setup_tc_taprio+0x170/0x47c
 enetc_setup_tc+0x38/0x2dc
 taprio_change+0x43c/0x970
 taprio_init+0x188/0x1e0
 qdisc_create+0x114/0x470
 tc_modify_qdisc+0x1fc/0x6c0
 rtnetlink_rcv_msg+0x12c/0x390

Split enetc_setup_tc() into separate functions for the PF and for the
VF drivers. Also remove enetc_qos.o from being included into
enetc-vf.ko, since it serves absolutely no purpose there.

Fixes: 34c6adf197 ("enetc: Configure the Time-Aware Scheduler via tc-taprio offload")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20220916133209.3351399-2-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-20 11:27:10 -07:00
Vladimir Oltean
e7d48e5fbf net: enetc: add a mini driver for the Integrated Endpoint Register Block
The NXP ENETC is a 4-port Ethernet controller which 'smells' to
operating systems like 4 distinct PCIe PFs with SR-IOV, each PF having
its own driver instance, but in fact there are some hardware resources
which are shared between all ports, like for example the 256 KB SRAM
FIFO between the MACs and the Host Transfer Agent which DMAs frames to
DRAM.

To hide the stuff that cannot be neatly exposed per port, the hardware
designers came up with this idea of having a dedicated register block
which is supposed to be populated by the bootloader, and contains
everything configuration-related: MAC addresses, FIFO partitioning, etc.

When a port is reset using PCIe Function Level Reset, its defaults are
transferred from the IERB configuration. Most of the time, the settings
made through the IERB are read-only in the port's memory space (if they
are even visible), so they cannot be modified at runtime.

Linux doesn't have any advanced FIFO partitioning requirements at all,
but when reading through the hardware manual, it became clear that, even
though there are many good 'recommendations' for default values, many of
them were not actually put in practice on LS1028A. So we end up with a
default configuration that:

(a) does not have enough TX and RX byte credits to support the max MTU
    of 9600 (which the Linux driver claims already) properly (at full speed)
(b) allows the FIFO to be overrun with RX traffic, potentially
    overwriting internal data structures.

The last part sounds a bit catastrophic, but it isn't. Frames are
supposed to transit the FIFO for a very short time, but they can
actually accumulate there under 2 conditions:

(a) there is very severe congestion on DRAM memory, or
(b) the RX rings visible to the operating system were configured for
    lossless operation, and they just ran out of free buffers to copy
    the frame to. This is what is used to put backpressure onto the MAC
    with flow control.

So since ENETC has not supported flow control thus far, RX FIFO overruns
were never seen with Linux. But with the addition of flow control, we
should configure some registers to prevent this from happening. What we
are trying to protect against are bad actors which continue to send us
traffic despite the fact that we have signaled a PAUSE condition. Of
course we can't be lossless in that case, but it is best to configure
the FIFO to do tail dropping rather than letting it overrun.

So in a nutshell, this driver is a fixup for all the IERB default values
that should have been but aren't.

The IERB configuration needs to be done _before_ the PFs are enabled.
So every PF searches for the presence of the "fsl,ls1028a-enetc-ierb"
node in the device tree, and if it finds it, it "registers" with the
IERB, which means that it requests the IERB to fix up its default
values. This is done through -EPROBE_DEFER. The IERB driver is part of
the fsl_enetc module, but is technically a platform driver, since the
IERB is a good old fashioned MMIO region, as opposed to ENETC ports
which pretend to be PCIe devices.

The driver was already configuring ENETC_PTXMBAR (FIFO allocation for
TX) because due to an omission, TXMBAR is a read/write register in the
PF memory space. But the manual is quite clear that the formula for this
should depend upon the TX byte credits (TXBCR). In turn, the TX byte
credits are only readable/writable through the IERB. So if we want to
ensure that the TXBCR register also has a value that is correct and in
line with TXMBAR, there is simply no way this can be done from the PF
driver, access to the IERB is needed.

I could have modified U-Boot to fix up the IERB values, but that is
quite undesirable, as old U-Boot versions are likely to be floating
around for quite some time from now.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-19 15:31:45 -07:00
Claudiu Manoil
6517798dd3 enetc: Make MDIO accessors more generic and export to include/linux/fsl
Within the LS1028A SoC, the register map for the ENETC MDIO controller
is instantiated a few times: for the central (external) MDIO controller,
for the internal bus of each standalone ENETC port, and for the internal
bus of the Felix switch.

Refactoring is needed to support multiple MDIO buses from multiple
drivers. The enetc_hw structure is made an opaque type and a smaller
enetc_mdio_priv is created.

'mdio_base' - MDIO registers base address - is being parameterized, to
be able to work with different MDIO register bases.

The ENETC MDIO bus operations are exported from the fsl-enetc-mdio
kernel object, the same that registers the central MDIO controller (the
dedicated PF). The ENETC main driver has been changed to select it, and
use its exported helpers to further register its private MDIO bus. The
DSA Felix driver will do the same.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-05 23:22:32 -08:00
Po Liu
34c6adf197 enetc: Configure the Time-Aware Scheduler via tc-taprio offload
ENETC supports in hardware for time-based egress shaping according
to IEEE 802.1Qbv. This patch implement the Qbv enablement by the
hardware offload method qdisc tc-taprio method.
Also update cbdr writeback to up level since control bd ring may
writeback data to control bd ring.

Signed-off-by: Po Liu <Po.Liu@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-16 12:49:16 -08:00
Claudiu Manoil
231ece36f5 enetc: Add mdio bus driver for the PCIe MDIO endpoint
ENETC ports can manage the MDIO bus via local register
interface.  However there's also a centralized way
to manage the MDIO bus, via the MDIO PCIe endpoint
device integrated by the same root complex that also
integrates the ENETC ports (eth controllers).

Depending on board design and use case, centralized
access to MDIO may be better than using local ENETC
port registers.  For instance, on the LS1028A QDS board
where MDIO muxing is required.  Also, the LS1028A on-chip
switch doesn't have a local MDIO register interface.

The current patch registers the above PCIe endpoint as a
separate MDIO bus and provides a driver for it by re-using
the code used for local MDIO access.  It also allows the
ENETC port PHYs to be managed by this driver if the local
"mdio" node is missing from the ENETC port node.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-02 18:22:18 -07:00
Claudiu Manoil
0c010a9deb enetc: Clean up makefile
Clean up overcomplicated makefile to make it more maintainable.
Basically, there's a set of common objects shared between
the PF and VF driver modules.  This can be implemented in a
simpler way, without conditionals, less repetition, allowing
also for easier updates in the future.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-02 18:22:18 -07:00
Claudiu Manoil
ebfcb23d62 enetc: Add ENETC PF level external MDIO support
Each ENETC PF has its own MDIO interface, the corresponding
MDIO registers are mapped in the ENETC's Port register block.
The current patch adds a driver for these PF level MDIO buses,
so that each PF can manage directly its own external link.

Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-01 11:21:32 -08:00
Yangbo Lu
19971f5ea0 enetc: add PTP clock driver
This patch is to add PTP clock driver for ENETC.
The driver reused QorIQ PTP clock driver.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12 12:58:48 -05:00
Claudiu Manoil
beb74ac878 enetc: Add vf to pf messaging support
VSIs (VFs) may send a message to the PSI (PF) for general notification
or to gain access to hardware resources which requires host inspection.
These messages may vary in size and are handled as a partition copy
between two memory regions owned by the respective participants.
The PSI will respond with fail or success and a 16-bit message code.
The patch implements the vf to pf messaging mechanism above and, as the
first application making use of this support, it enables the VF to
configure its own primary MAC address.

Signed-off-by: Catalin Horghidan <catalin.horghidan@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-24 21:55:53 -08:00
Claudiu Manoil
d4fd0404c1 enetc: Introduce basic PF and VF ENETC ethernet drivers
ENETC is a multi-port virtualized Ethernet controller supporting GbE
designs and Time-Sensitive Networking (TSN) functionality.
ENETC is operating as an SR-IOV multi-PF capable Root Complex Integrated
Endpoint (RCIE).  As such, it contains multiple physical (PF) and
virtual (VF) PCIe functions, discoverable by standard PCI Express.

Introduce basic PF and VF ENETC ethernet drivers.  The PF has access to
the ENETC Port registers and resources and makes the required privileged
configurations for the underlying VF devices.  Common functionality is
controlled through so called System Interface (SI) register blocks, PFs
and VFs own a SI each.  Though SI register blocks are almost identical,
there are a few privileged SI level controls that are accessible only to
PFs, and so the distinction is made between PF SIs (PSI) and VF SIs (VSI).
As such, the bulk of the code, including datapath processing, basic h/w
offload support and generic pci related configuration, is shared between
the 2 drivers and is factored out in common source files (i.e. enetc.c).

Major functionalities included (for both drivers):
MSI-X support for Rx and Tx processing, assignment of Rx/Tx BD ring pairs
to MSI-X entries, multi-queue support, Rx S/G (Rx frame fragmentation) and
jumbo frame (up to 9600B) support, Rx paged allocation and reuse, Tx S/G
support (NETIF_F_SG), Rx and Tx checksum offload, PF MAC filtering and
initial control ring support, VLAN extraction/ insertion, PF Rx VLAN
CTAG filtering, VF mac address config support, VF VLAN isolation support,
etc.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-24 21:55:53 -08:00