| .. SPDX-License-Identifier: GPL-2.0 |
| |
| .. include:: <isonum.txt> |
| |
| ======================================= |
| Altera Triple-Speed Ethernet MAC driver |
| ======================================= |
| |
| Copyright |copy| 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 separately. 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 initiates 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 |
| initialization. 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: |
| -------------------------- |
| - Kconfig |
| - Makefile |
| - altera_tse_main.c: main network device driver |
| - altera_tse_ethtool.c: ethtool support |
| - altera_tse.h: private driver structure and common definitions |
| - altera_msgdma.h: MSGDMA implementation function definitions |
| - altera_sgdma.h: SGDMA implementation function definitions |
| - altera_msgdma.c: MSGDMA implementation |
| - altera_sgdma.c: SGDMA implementation |
| - altera_sgdmahw.h: SGDMA register and descriptor definitions |
| - altera_msgdmahw.h: MSGDMA register and descriptor definitions |
| - altera_utils.c: Driver utility functions |
| - 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: |
| |
| - IEEE 802.3-2012 - IEEE Standard for Ethernet. |
| - RFC 2863 found at http://www.rfc-editor.org/rfc/rfc2863.txt. |
| - RFC 2819 found at http://www.rfc-editor.org/rfc/rfc2819.txt. |
| - 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). |
