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+ Altera Triple-Speed Ethernet MAC driver
+
+Copyright (C) 2008-2014 Altera Corporation
+
+This is the driver for the Altera Triple-Speed Ethernet (TSE) controllers
+using the SGDMA and MSGDMA soft DMA IP components. The driver uses the
+platform bus to obtain component resources. The designs used to test this
+driver were built for a Cyclone(R) V SOC FPGA board, a Cyclone(R) V FPGA board,
+and tested with ARM and NIOS processor hosts seperately. The anticipated use
+cases are simple communications between an embedded system and an external peer
+for status and simple configuration of the embedded system.
+
+For more information visit www.altera.com and www.rocketboards.org. Support
+forums for the driver may be found on www.rocketboards.org, and a design used
+to test this driver may be found there as well. Support is also available from
+the maintainer of this driver, found in MAINTAINERS.
+
+The Triple-Speed Ethernet, SGDMA, and MSGDMA components are all soft IP
+components that can be assembled and built into an FPGA using the Altera
+Quartus toolchain. Quartus 13.1 and 14.0 were used to build the design that
+this driver was tested against. The sopc2dts tool is used to create the
+device tree for the driver, and may be found at rocketboards.org.
+
+The driver probe function examines the device tree and determines if the
+Triple-Speed Ethernet instance is using an SGDMA or MSGDMA component. The
+probe function then installs the appropriate set of DMA routines to
+initialize, setup transmits, receives, and interrupt handling primitives for
+the respective configurations.
+
+The SGDMA component is to be deprecated in the near future (over the next 1-2
+years as of this writing in early 2014) in favor of the MSGDMA component.
+SGDMA support is included for existing designs and reference in case a
+developer wishes to support their own soft DMA logic and driver support. Any
+new designs should not use the SGDMA.
+
+The SGDMA supports only a single transmit or receive operation at a time, and
+therefore will not perform as well compared to the MSGDMA soft IP. Please
+visit www.altera.com for known, documented SGDMA errata.
+
+Scatter-gather DMA is not supported by the SGDMA or MSGDMA at this time.
+Scatter-gather DMA will be added to a future maintenance update to this
+driver.
+
+Jumbo frames are not supported at this time.
+
+The driver limits PHY operations to 10/100Mbps, and has not yet been fully
+tested for 1Gbps. This support will be added in a future maintenance update.
+
+1) Kernel Configuration
+The kernel configuration option is ALTERA_TSE:
+ Device Drivers ---> Network device support ---> Ethernet driver support --->
+ Altera Triple-Speed Ethernet MAC support (ALTERA_TSE)
+
+2) Driver parameters list:
+ debug: message level (0: no output, 16: all);
+ dma_rx_num: Number of descriptors in the RX list (default is 64);
+ dma_tx_num: Number of descriptors in the TX list (default is 64).
+
+3) Command line options
+Driver parameters can be also passed in command line by using:
+ altera_tse=dma_rx_num:128,dma_tx_num:512
+
+4) Driver information and notes
+
+4.1) Transmit process
+When the driver's transmit routine is called by the kernel, it sets up a
+transmit descriptor by calling the underlying DMA transmit routine (SGDMA or
+MSGDMA), and initites a transmit operation. Once the transmit is complete, an
+interrupt is driven by the transmit DMA logic. The driver handles the transmit
+completion in the context of the interrupt handling chain by recycling
+resource required to send and track the requested transmit operation.
+
+4.2) Receive process
+The driver will post receive buffers to the receive DMA logic during driver
+intialization. Receive buffers may or may not be queued depending upon the
+underlying DMA logic (MSGDMA is able queue receive buffers, SGDMA is not able
+to queue receive buffers to the SGDMA receive logic). When a packet is
+received, the DMA logic generates an interrupt. The driver handles a receive
+interrupt by obtaining the DMA receive logic status, reaping receive
+completions until no more receive completions are available.
+
+4.3) Interrupt Mitigation
+The driver is able to mitigate the number of its DMA interrupts
+using NAPI for receive operations. Interrupt mitigation is not yet supported
+for transmit operations, but will be added in a future maintenance release.
+
+4.4) Ethtool support
+Ethtool is supported. Driver statistics and internal errors can be taken using:
+ethtool -S ethX command. It is possible to dump registers etc.
+
+4.5) PHY Support
+The driver is compatible with PAL to work with PHY and GPHY devices.
+
+4.7) List of source files:
+ o Kconfig
+ o Makefile
+ o altera_tse_main.c: main network device driver
+ o altera_tse_ethtool.c: ethtool support
+ o altera_tse.h: private driver structure and common definitions
+ o altera_msgdma.h: MSGDMA implementation function definitions
+ o altera_sgdma.h: SGDMA implementation function definitions
+ o altera_msgdma.c: MSGDMA implementation
+ o altera_sgdma.c: SGDMA implementation
+ o altera_sgdmahw.h: SGDMA register and descriptor definitions
+ o altera_msgdmahw.h: MSGDMA register and descriptor definitions
+ o altera_utils.c: Driver utility functions
+ o altera_utils.h: Driver utility function definitions
+
+5) Debug Information
+
+The driver exports debug information such as internal statistics,
+debug information, MAC and DMA registers etc.
+
+A user may use the ethtool support to get statistics:
+e.g. using: ethtool -S ethX (that shows the statistics counters)
+or sees the MAC registers: e.g. using: ethtool -d ethX
+
+The developer can also use the "debug" module parameter to get
+further debug information.
+
+6) Statistics Support
+
+The controller and driver support a mix of IEEE standard defined statistics,
+RFC defined statistics, and driver or Altera defined statistics. The four
+specifications containing the standard definitions for these statistics are
+as follows:
+
+ o IEEE 802.3-2012 - IEEE Standard for Ethernet.
+ o RFC 2863 found at http://www.rfc-editor.org/rfc/rfc2863.txt.
+ o RFC 2819 found at http://www.rfc-editor.org/rfc/rfc2819.txt.
+ o Altera Triple Speed Ethernet User Guide, found at http://www.altera.com
+
+The statistics supported by the TSE and the device driver are as follows:
+
+"tx_packets" is equivalent to aFramesTransmittedOK defined in IEEE 802.3-2012,
+Section 5.2.2.1.2. This statistics is the count of frames that are successfully
+transmitted.
+
+"rx_packets" is equivalent to aFramesReceivedOK defined in IEEE 802.3-2012,
+Section 5.2.2.1.5. This statistic is the count of frames that are successfully
+received. This count does not include any error packets such as CRC errors,
+length errors, or alignment errors.
+
+"rx_crc_errors" is equivalent to aFrameCheckSequenceErrors defined in IEEE
+802.3-2012, Section 5.2.2.1.6. This statistic is the count of frames that are
+an integral number of bytes in length and do not pass the CRC test as the frame
+is received.
+
+"rx_align_errors" is equivalent to aAlignmentErrors defined in IEEE 802.3-2012,
+Section 5.2.2.1.7. This statistic is the count of frames that are not an
+integral number of bytes in length and do not pass the CRC test as the frame is
+received.
+
+"tx_bytes" is equivalent to aOctetsTransmittedOK defined in IEEE 802.3-2012,
+Section 5.2.2.1.8. This statistic is the count of data and pad bytes
+successfully transmitted from the interface.
+
+"rx_bytes" is equivalent to aOctetsReceivedOK defined in IEEE 802.3-2012,
+Section 5.2.2.1.14. This statistic is the count of data and pad bytes
+successfully received by the controller.
+
+"tx_pause" is equivalent to aPAUSEMACCtrlFramesTransmitted defined in IEEE
+802.3-2012, Section 30.3.4.2. This statistic is a count of PAUSE frames
+transmitted from the network controller.
+
+"rx_pause" is equivalent to aPAUSEMACCtrlFramesReceived defined in IEEE
+802.3-2012, Section 30.3.4.3. This statistic is a count of PAUSE frames
+received by the network controller.
+
+"rx_errors" is equivalent to ifInErrors defined in RFC 2863. This statistic is
+a count of the number of packets received containing errors that prevented the
+packet from being delivered to a higher level protocol.
+
+"tx_errors" is equivalent to ifOutErrors defined in RFC 2863. This statistic
+is a count of the number of packets that could not be transmitted due to errors.
+
+"rx_unicast" is equivalent to ifInUcastPkts defined in RFC 2863. This
+statistic is a count of the number of packets received that were not addressed
+to the broadcast address or a multicast group.
+
+"rx_multicast" is equivalent to ifInMulticastPkts defined in RFC 2863. This
+statistic is a count of the number of packets received that were addressed to
+a multicast address group.
+
+"rx_broadcast" is equivalent to ifInBroadcastPkts defined in RFC 2863. This
+statistic is a count of the number of packets received that were addressed to
+the broadcast address.
+
+"tx_discards" is equivalent to ifOutDiscards defined in RFC 2863. This
+statistic is the number of outbound packets not transmitted even though an
+error was not detected. An example of a reason this might occur is to free up
+internal buffer space.
+
+"tx_unicast" is equivalent to ifOutUcastPkts defined in RFC 2863. This
+statistic counts the number of packets transmitted that were not addressed to
+a multicast group or broadcast address.
+
+"tx_multicast" is equivalent to ifOutMulticastPkts defined in RFC 2863. This
+statistic counts the number of packets transmitted that were addressed to a
+multicast group.
+
+"tx_broadcast" is equivalent to ifOutBroadcastPkts defined in RFC 2863. This
+statistic counts the number of packets transmitted that were addressed to a
+broadcast address.
+
+"ether_drops" is equivalent to etherStatsDropEvents defined in RFC 2819.
+This statistic counts the number of packets dropped due to lack of internal
+controller resources.
+
+"rx_total_bytes" is equivalent to etherStatsOctets defined in RFC 2819.
+This statistic counts the total number of bytes received by the controller,
+including error and discarded packets.
+
+"rx_total_packets" is equivalent to etherStatsPkts defined in RFC 2819.
+This statistic counts the total number of packets received by the controller,
+including error, discarded, unicast, multicast, and broadcast packets.
+
+"rx_undersize" is equivalent to etherStatsUndersizePkts defined in RFC 2819.
+This statistic counts the number of correctly formed packets received less
+than 64 bytes long.
+
+"rx_oversize" is equivalent to etherStatsOversizePkts defined in RFC 2819.
+This statistic counts the number of correctly formed packets greater than 1518
+bytes long.
+
+"rx_64_bytes" is equivalent to etherStatsPkts64Octets defined in RFC 2819.
+This statistic counts the total number of packets received that were 64 octets
+in length.
+
+"rx_65_127_bytes" is equivalent to etherStatsPkts65to127Octets defined in RFC
+2819. This statistic counts the total number of packets received that were
+between 65 and 127 octets in length inclusive.
+
+"rx_128_255_bytes" is equivalent to etherStatsPkts128to255Octets defined in
+RFC 2819. This statistic is the total number of packets received that were
+between 128 and 255 octets in length inclusive.
+
+"rx_256_511_bytes" is equivalent to etherStatsPkts256to511Octets defined in
+RFC 2819. This statistic is the total number of packets received that were
+between 256 and 511 octets in length inclusive.
+
+"rx_512_1023_bytes" is equivalent to etherStatsPkts512to1023Octets defined in
+RFC 2819. This statistic is the total number of packets received that were
+between 512 and 1023 octets in length inclusive.
+
+"rx_1024_1518_bytes" is equivalent to etherStatsPkts1024to1518Octets define
+in RFC 2819. This statistic is the total number of packets received that were
+between 1024 and 1518 octets in length inclusive.
+
+"rx_gte_1519_bytes" is a statistic defined specific to the behavior of the
+Altera TSE. This statistics counts the number of received good and errored
+frames between the length of 1519 and the maximum frame length configured
+in the frm_length register. See the Altera TSE User Guide for More details.
+
+"rx_jabbers" is equivalent to etherStatsJabbers defined in RFC 2819. This
+statistic is the total number of packets received that were longer than 1518
+octets, and had either a bad CRC with an integral number of octets (CRC Error)
+or a bad CRC with a non-integral number of octets (Alignment Error).
+
+"rx_runts" is equivalent to etherStatsFragments defined in RFC 2819. This
+statistic is the total number of packets received that were less than 64 octets
+in length and had either a bad CRC with an integral number of octets (CRC
+error) or a bad CRC with a non-integral number of octets (Alignment Error).