Commit 337d1ccb authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'Add-gve-driver' 



Catherine Sullivan says:

====================
Add gve driver

This patch series adds the gve driver which will support the
Compute Engine Virtual NIC that will be available in the future.

v2:
- Patch 1:
  - Remove gve_size_assert.h and use static_assert instead.
  - Loop forever instead of bugging if the device won't reset
  - Use module_pci_driver
- Patch 2:
  - Use be16_to_cpu in the RX Seq No define
  - Remove unneeded ndo_change_mtu
- Patch 3:
  - No Changes
- Patch 4:
  - Instead of checking netif_carrier_ok in ethtool stats, just make sure

v3:
- Patch 1:
  - Remove X86 dep
- Patch 2:
  - No changes
- Patch 3:
  - No changes
- Patch 4:
  - Remove unneeded memsets in ethtool stats

v4:
- Patch 1:
  - Use io[read|write]32be instead of [read|write]l(cpu_to_be32())
  - Explicitly add padding to gve_adminq_set_driver_parameter
  - Use static where appropriate
- Patch 2:
  - Use u64_stats_sync
  - Explicity add padding to gve_adminq_create_rx_queue
  - Fix some enianness typing issues found by kbuild
  - Use static where appropriate
  - Remove unused variables
- Patch 3:
  - Use io[read|write]32be instead of [read|write]l(cpu_to_be32())
- Patch 4:
  - Use u64_stats_sync
  - Use static where appropriate
Warnings reported by:
Reported-by: default avatarkbuild test robot <lkp@intel.com>
Reported-by: default avatarJulia Lawall <julia.lawall@lip6.fr>
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 2a8d8e0f e5b845dc

Documentation/networking/device_drivers/google/gve.rst

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Original line number Diff line number Diff line 
.. SPDX-License-Identifier: GPL-2.0+



==============================================================

Linux kernel driver for Compute Engine Virtual Ethernet (gve):

==============================================================



Supported Hardware

===================

The GVE driver binds to a single PCI device id used by the virtual

Ethernet device found in some Compute Engine VMs.



+--------------+----------+---------+

|Field         | Value    | Comments|

+==============+==========+=========+

|Vendor ID     | `0x1AE0` | Google  |

+--------------+----------+---------+

|Device ID     | `0x0042` |         |

+--------------+----------+---------+

|Sub-vendor ID | `0x1AE0` | Google  |

+--------------+----------+---------+

|Sub-device ID | `0x0058` |         |

+--------------+----------+---------+

|Revision ID   | `0x0`    |         |

+--------------+----------+---------+

|Device Class  | `0x200`  | Ethernet|

+--------------+----------+---------+



PCI Bars

========

The gVNIC PCI device exposes three 32-bit memory BARS:

- Bar0 - Device configuration and status registers.

- Bar1 - MSI-X vector table

- Bar2 - IRQ, RX and TX doorbells



Device Interactions

===================

The driver interacts with the device in the following ways:

 - Registers

    - A block of MMIO registers

    - See gve_register.h for more detail

 - Admin Queue

    - See description below

 - Reset

    - At any time the device can be reset

 - Interrupts

    - See supported interrupts below

 - Transmit and Receive Queues

    - See description below



Registers

---------

All registers are MMIO and big endian.



The registers are used for initializing and configuring the device as well as

querying device status in response to management interrupts.



Admin Queue (AQ)

----------------

The Admin Queue is a PAGE_SIZE memory block, treated as an array of AQ

commands, used by the driver to issue commands to the device and set up

resources.The driver and the device maintain a count of how many commands

have been submitted and executed. To issue AQ commands, the driver must do

the following (with proper locking):



1)  Copy new commands into next available slots in the AQ array

2)  Increment its counter by he number of new commands

3)  Write the counter into the GVE_ADMIN_QUEUE_DOORBELL register

4)  Poll the ADMIN_QUEUE_EVENT_COUNTER register until it equals

    the value written to the doorbell, or until a timeout.



The device will update the status field in each AQ command reported as

executed through the ADMIN_QUEUE_EVENT_COUNTER register.



Device Resets

-------------

A device reset is triggered by writing 0x0 to the AQ PFN register.

This causes the device to release all resources allocated by the

driver, including the AQ itself.



Interrupts

----------

The following interrupts are supported by the driver:



Management Interrupt

~~~~~~~~~~~~~~~~~~~~

The management interrupt is used by the device to tell the driver to

look at the GVE_DEVICE_STATUS register.



The handler for the management irq simply queues the service task in

the workqueue to check the register and acks the irq.



Notification Block Interrupts

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The notification block interrupts are used to tell the driver to poll

the queues associated with that interrupt.



The handler for these irqs schedule the napi for that block to run

and poll the queues.



Traffic Queues

--------------

gVNIC's queues are composed of a descriptor ring and a buffer and are

assigned to a notification block.



The descriptor rings are power-of-two-sized ring buffers consisting of

fixed-size descriptors. They advance their head pointer using a __be32

doorbell located in Bar2. The tail pointers are advanced by consuming

descriptors in-order and updating a __be32 counter. Both the doorbell

and the counter overflow to zero.



Each queue's buffers must be registered in advance with the device as a

queue page list, and packet data can only be put in those pages.



Transmit

~~~~~~~~

gve maps the buffers for transmit rings into a FIFO and copies the packets

into the FIFO before sending them to the NIC.



Receive

~~~~~~~

The buffers for receive rings are put into a data ring that is the same

length as the descriptor ring and the head and tail pointers advance over

the rings together.

Documentation/networking/device_drivers/index.rst

+1 −0
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ Contents: 
   intel/i40e

   intel/iavf

   intel/ice

   google/gve

   mellanox/mlx5



.. only::  subproject

MAINTAINERS

+9 −0
Original line number Diff line number Diff line
@@ -6720,6 +6720,15 @@ L: linux-input@vger.kernel.org 
S:	Maintained

F:	drivers/input/touchscreen/goodix.c



GOOGLE ETHERNET DRIVERS

M:	Catherine Sullivan <csully@google.com>

R:	Sagi Shahar <sagis@google.com>

R:	Jon Olson <jonolson@google.com>

L:	netdev@vger.kernel.org

S:	Supported

F:	Documentation/networking/device_drivers/google/gve.txt

F:	drivers/net/ethernet/google



GPD POCKET FAN DRIVER

M:	Hans de Goede <hdegoede@redhat.com>

L:	platform-driver-x86@vger.kernel.org

drivers/net/ethernet/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -76,6 +76,7 @@ source "drivers/net/ethernet/ezchip/Kconfig" 
source "drivers/net/ethernet/faraday/Kconfig"

source "drivers/net/ethernet/freescale/Kconfig"

source "drivers/net/ethernet/fujitsu/Kconfig"

source "drivers/net/ethernet/google/Kconfig"

source "drivers/net/ethernet/hisilicon/Kconfig"

source "drivers/net/ethernet/hp/Kconfig"

source "drivers/net/ethernet/huawei/Kconfig"

drivers/net/ethernet/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ obj-$(CONFIG_NET_VENDOR_EZCHIP) += ezchip/ 
obj-$(CONFIG_NET_VENDOR_FARADAY) += faraday/

obj-$(CONFIG_NET_VENDOR_FREESCALE) += freescale/

obj-$(CONFIG_NET_VENDOR_FUJITSU) += fujitsu/

obj-$(CONFIG_NET_VENDOR_GOOGLE) += google/

obj-$(CONFIG_NET_VENDOR_HISILICON) += hisilicon/

obj-$(CONFIG_NET_VENDOR_HP) += hp/

obj-$(CONFIG_NET_VENDOR_HUAWEI) += huawei/

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