Commit Graph

6 Commits

Author SHA1 Message Date
Jonathan Neuschäfer d81f41411c net: nps_enet: Fix function names in doc comments
Adjust the function names in two doc comments to match the corresponding
functions.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-11 21:32:33 -07:00
Thomas Gleixner 4fa9c49f4d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 291
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms and conditions of the gnu general public license
  version 2 as published by the free software foundation this program
  is distributed in the hope it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details the full gnu general public license is included in
  this distribution in the file called copying

  this program is free software you can redistribute it and or modify
  it under the terms and conditions of the gnu general public license
  version 2 as published by the free software foundation this program
  is distributed in the hope [that] it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details the full gnu general public license is included in
  this distribution in the file called copying

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 57 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.515993066@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:38 +02:00
Elad Kanfi e5df49d564 net: nps_enet: Tx handler synchronization
Below is a description of a possible problematic
sequence. CPU-A is sending a frame and CPU-B handles
the interrupt that indicates the frame was sent. CPU-B
reads an invalid value of tx_packet_sent.

	CPU-A				CPU-B
	-----				-----
	nps_enet_send_frame
	.
	.
	tx_skb = skb
	tx_packet_sent = true
	order HW to start tx
	.
	.
	HW complete tx
			    ------> 	get tx complete interrupt
					.
					.
					if(tx_packet_sent == true)
						handle tx_skb

	end memory transaction
	(tx_packet_sent actually
	 written)

Furthermore there is a dependency between tx_skb and tx_packet_sent.
There is no assurance that tx_skb contains a valid pointer at CPU B
when it sees tx_packet_sent == true.

Solution:

Initialize tx_skb to NULL and use it to indicate that packet was sent,
in this way tx_packet_sent can be removed.
Add a write memory barrier after setting tx_skb in order to make sure
that it is valid before HW is informed and IRQ is fired.

Fixed sequence will be:

       CPU-A                           CPU-B
       -----                           -----

	tx_skb = skb
	wmb()
	.
	.
	order HW to start tx
	.
	.
	HW complete tx
			------>		get tx complete interrupt
					.
					.
					if(tx_skb != NULL)
						handle tx_skb

					tx_skb = NULL

Signed-off-by: Elad Kanfi <eladkan@mellanox.com>
Acked-by: Noam Camus <noamca@mellanox.com>
Acked-by: Gilad Ben-Yossef <giladby@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-10 15:04:49 -04:00
Lada Trimasova b54b8c2d6e net: ezchip: adapt driver to little endian architecture
Since ezchip network driver is written with big endian EZChip platform it
is necessary to add support for little endian architecture.

The first issue is that the order of the bits in a bit field is
implementation specific. So all the bit fields are removed.
Named constants are used to access necessary fields.

And the second one is that network byte order is big endian.
For example, data on ethernet is transmitted with most-significant
octet (byte) first. So in case of little endian architecture
it is important to swap data byte order when we read it from
register. In case of unaligned access we can use "get_unaligned_be32"
and in other case we can use function "ioread32_rep" which reads all
data from register and works either with little endian or big endian
architecture.

And then when we are going to write data to register we need to restore
byte order using the function "put_unaligned_be32" in case of
unaligned access and in other case "iowrite32_rep".

The last little fix is a space between type and pointer to observe
coding style.

Signed-off-by: Lada Trimasova <ltrimas@synopsys.com>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Tal Zilcer <talz@ezchip.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-03 17:20:08 -05:00
Noam Camus 0dd20f3ce0 NET: nps_enet: replace use of cause register
When interrupt is received we read directly from control
register for RX/TX instead of reading cause register
since this register fails to indicate TX done when
TX interrupt is "edge mode".

Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-23 16:08:53 -07:00
Noam Camus 0dd0770936 NET: Add ezchip ethernet driver
Simple LAN device for debug or management purposes.
Device supports interrupts for RX and TX(completion).
Device does not have DMA ability.

Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Tal Zilcer <talz@ezchip.com>
Acked-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-23 07:16:25 -07:00