1.. SPDX-License-Identifier: GPL-2.0
2
3.. include:: <isonum.txt>
4
5=======================================
6Altera Triple-Speed Ethernet MAC driver
7=======================================
8
9Copyright |copy| 2008-2014 Altera Corporation
10
11This is the driver for the Altera Triple-Speed Ethernet (TSE) controllers
12using the SGDMA and MSGDMA soft DMA IP components. The driver uses the
13platform bus to obtain component resources. The designs used to test this
14driver were built for a Cyclone(R) V SOC FPGA board, a Cyclone(R) V FPGA board,
15and tested with ARM and NIOS processor hosts separately. The anticipated use
16cases are simple communications between an embedded system and an external peer
17for status and simple configuration of the embedded system.
18
19For more information visit www.altera.com and www.rocketboards.org. Support
20forums for the driver may be found on www.rocketboards.org, and a design used
21to test this driver may be found there as well. Support is also available from
22the maintainer of this driver, found in MAINTAINERS.
23
24The Triple-Speed Ethernet, SGDMA, and MSGDMA components are all soft IP
25components that can be assembled and built into an FPGA using the Altera
26Quartus toolchain. Quartus 13.1 and 14.0 were used to build the design that
27this driver was tested against. The sopc2dts tool is used to create the
28device tree for the driver, and may be found at rocketboards.org.
29
30The driver probe function examines the device tree and determines if the
31Triple-Speed Ethernet instance is using an SGDMA or MSGDMA component. The
32probe function then installs the appropriate set of DMA routines to
33initialize, setup transmits, receives, and interrupt handling primitives for
34the respective configurations.
35
36The SGDMA component is to be deprecated in the near future (over the next 1-2
37years as of this writing in early 2014) in favor of the MSGDMA component.
38SGDMA support is included for existing designs and reference in case a
39developer wishes to support their own soft DMA logic and driver support. Any
40new designs should not use the SGDMA.
41
42The SGDMA supports only a single transmit or receive operation at a time, and
43therefore will not perform as well compared to the MSGDMA soft IP. Please
44visit www.altera.com for known, documented SGDMA errata.
45
46Scatter-gather DMA is not supported by the SGDMA or MSGDMA at this time.
47Scatter-gather DMA will be added to a future maintenance update to this
48driver.
49
50Jumbo frames are not supported at this time.
51
52The driver limits PHY operations to 10/100Mbps, and has not yet been fully
53tested for 1Gbps. This support will be added in a future maintenance update.
54
551. Kernel Configuration
56=======================
57
58The kernel configuration option is ALTERA_TSE:
59
60 Device Drivers ---> Network device support ---> Ethernet driver support --->
61 Altera Triple-Speed Ethernet MAC support (ALTERA_TSE)
62
632. Driver parameters list
64=========================
65
66	- debug: message level (0: no output, 16: all);
67	- dma_rx_num: Number of descriptors in the RX list (default is 64);
68	- dma_tx_num: Number of descriptors in the TX list (default is 64).
69
703. Command line options
71=======================
72
73Driver parameters can be also passed in command line by using::
74
75	altera_tse=dma_rx_num:128,dma_tx_num:512
76
774. Driver information and notes
78===============================
79
804.1. Transmit process
81---------------------
82When the driver's transmit routine is called by the kernel, it sets up a
83transmit descriptor by calling the underlying DMA transmit routine (SGDMA or
84MSGDMA), and initiates a transmit operation. Once the transmit is complete, an
85interrupt is driven by the transmit DMA logic. The driver handles the transmit
86completion in the context of the interrupt handling chain by recycling
87resource required to send and track the requested transmit operation.
88
894.2. Receive process
90--------------------
91The driver will post receive buffers to the receive DMA logic during driver
92initialization. Receive buffers may or may not be queued depending upon the
93underlying DMA logic (MSGDMA is able queue receive buffers, SGDMA is not able
94to queue receive buffers to the SGDMA receive logic). When a packet is
95received, the DMA logic generates an interrupt. The driver handles a receive
96interrupt by obtaining the DMA receive logic status, reaping receive
97completions until no more receive completions are available.
98
994.3. Interrupt Mitigation
100-------------------------
101The driver is able to mitigate the number of its DMA interrupts
102using NAPI for receive operations. Interrupt mitigation is not yet supported
103for transmit operations, but will be added in a future maintenance release.
104
1054.4) Ethtool support
106--------------------
107Ethtool is supported. Driver statistics and internal errors can be taken using:
108ethtool -S ethX command. It is possible to dump registers etc.
109
1104.5) PHY Support
111----------------
112The driver is compatible with PAL to work with PHY and GPHY devices.
113
1144.7) List of source files:
115--------------------------
116 - Kconfig
117 - Makefile
118 - altera_tse_main.c: main network device driver
119 - altera_tse_ethtool.c: ethtool support
120 - altera_tse.h: private driver structure and common definitions
121 - altera_msgdma.h: MSGDMA implementation function definitions
122 - altera_sgdma.h: SGDMA implementation function definitions
123 - altera_msgdma.c: MSGDMA implementation
124 - altera_sgdma.c: SGDMA implementation
125 - altera_sgdmahw.h: SGDMA register and descriptor definitions
126 - altera_msgdmahw.h: MSGDMA register and descriptor definitions
127 - altera_utils.c: Driver utility functions
128 - altera_utils.h: Driver utility function definitions
129
1305. Debug Information
131====================
132
133The driver exports debug information such as internal statistics,
134debug information, MAC and DMA registers etc.
135
136A user may use the ethtool support to get statistics:
137e.g. using: ethtool -S ethX (that shows the statistics counters)
138or sees the MAC registers: e.g. using: ethtool -d ethX
139
140The developer can also use the "debug" module parameter to get
141further debug information.
142
1436. Statistics Support
144=====================
145
146The controller and driver support a mix of IEEE standard defined statistics,
147RFC defined statistics, and driver or Altera defined statistics. The four
148specifications containing the standard definitions for these statistics are
149as follows:
150
151 - IEEE 802.3-2012 - IEEE Standard for Ethernet.
152 - RFC 2863 found at http://www.rfc-editor.org/rfc/rfc2863.txt.
153 - RFC 2819 found at http://www.rfc-editor.org/rfc/rfc2819.txt.
154 - Altera Triple Speed Ethernet User Guide, found at http://www.altera.com
155
156The statistics supported by the TSE and the device driver are as follows:
157
158"tx_packets" is equivalent to aFramesTransmittedOK defined in IEEE 802.3-2012,
159Section 5.2.2.1.2. This statistics is the count of frames that are successfully
160transmitted.
161
162"rx_packets" is equivalent to aFramesReceivedOK defined in IEEE 802.3-2012,
163Section 5.2.2.1.5. This statistic is the count of frames that are successfully
164received. This count does not include any error packets such as CRC errors,
165length errors, or alignment errors.
166
167"rx_crc_errors" is equivalent to aFrameCheckSequenceErrors defined in IEEE
168802.3-2012, Section 5.2.2.1.6. This statistic is the count of frames that are
169an integral number of bytes in length and do not pass the CRC test as the frame
170is received.
171
172"rx_align_errors" is equivalent to aAlignmentErrors defined in IEEE 802.3-2012,
173Section 5.2.2.1.7. This statistic is the count of frames that are not an
174integral number of bytes in length and do not pass the CRC test as the frame is
175received.
176
177"tx_bytes" is equivalent to aOctetsTransmittedOK defined in IEEE 802.3-2012,
178Section 5.2.2.1.8. This statistic is the count of data and pad bytes
179successfully transmitted from the interface.
180
181"rx_bytes" is equivalent to aOctetsReceivedOK defined in IEEE 802.3-2012,
182Section 5.2.2.1.14. This statistic is the count of data and pad bytes
183successfully received by the controller.
184
185"tx_pause" is equivalent to aPAUSEMACCtrlFramesTransmitted defined in IEEE
186802.3-2012, Section 30.3.4.2. This statistic is a count of PAUSE frames
187transmitted from the network controller.
188
189"rx_pause" is equivalent to aPAUSEMACCtrlFramesReceived defined in IEEE
190802.3-2012, Section 30.3.4.3. This statistic is a count of PAUSE frames
191received by the network controller.
192
193"rx_errors" is equivalent to ifInErrors defined in RFC 2863. This statistic is
194a count of the number of packets received containing errors that prevented the
195packet from being delivered to a higher level protocol.
196
197"tx_errors" is equivalent to ifOutErrors defined in RFC 2863. This statistic
198is a count of the number of packets that could not be transmitted due to errors.
199
200"rx_unicast" is equivalent to ifInUcastPkts defined in RFC 2863. This
201statistic is a count of the number of packets received that were not addressed
202to the broadcast address or a multicast group.
203
204"rx_multicast" is equivalent to ifInMulticastPkts defined in RFC 2863. This
205statistic is a count of the number of packets received that were addressed to
206a multicast address group.
207
208"rx_broadcast" is equivalent to ifInBroadcastPkts defined in RFC 2863. This
209statistic is a count of the number of packets received that were addressed to
210the broadcast address.
211
212"tx_discards" is equivalent to ifOutDiscards defined in RFC 2863. This
213statistic is the number of outbound packets not transmitted even though an
214error was not detected. An example of a reason this might occur is to free up
215internal buffer space.
216
217"tx_unicast" is equivalent to ifOutUcastPkts defined in RFC 2863. This
218statistic counts the number of packets transmitted that were not addressed to
219a multicast group or broadcast address.
220
221"tx_multicast" is equivalent to ifOutMulticastPkts defined in RFC 2863. This
222statistic counts the number of packets transmitted that were addressed to a
223multicast group.
224
225"tx_broadcast" is equivalent to ifOutBroadcastPkts defined in RFC 2863. This
226statistic counts the number of packets transmitted that were addressed to a
227broadcast address.
228
229"ether_drops" is equivalent to etherStatsDropEvents defined in RFC 2819.
230This statistic counts the number of packets dropped due to lack of internal
231controller resources.
232
233"rx_total_bytes" is equivalent to etherStatsOctets defined in RFC 2819.
234This statistic counts the total number of bytes received by the controller,
235including error and discarded packets.
236
237"rx_total_packets" is equivalent to etherStatsPkts defined in RFC 2819.
238This statistic counts the total number of packets received by the controller,
239including error, discarded, unicast, multicast, and broadcast packets.
240
241"rx_undersize" is equivalent to etherStatsUndersizePkts defined in RFC 2819.
242This statistic counts the number of correctly formed packets received less
243than 64 bytes long.
244
245"rx_oversize" is equivalent to etherStatsOversizePkts defined in RFC 2819.
246This statistic counts the number of correctly formed packets greater than 1518
247bytes long.
248
249"rx_64_bytes" is equivalent to etherStatsPkts64Octets defined in RFC 2819.
250This statistic counts the total number of packets received that were 64 octets
251in length.
252
253"rx_65_127_bytes" is equivalent to etherStatsPkts65to127Octets defined in RFC
2542819. This statistic counts the total number of packets received that were
255between 65 and 127 octets in length inclusive.
256
257"rx_128_255_bytes" is equivalent to etherStatsPkts128to255Octets defined in
258RFC 2819. This statistic is the total number of packets received that were
259between 128 and 255 octets in length inclusive.
260
261"rx_256_511_bytes" is equivalent to etherStatsPkts256to511Octets defined in
262RFC 2819. This statistic is the total number of packets received that were
263between 256 and 511 octets in length inclusive.
264
265"rx_512_1023_bytes" is equivalent to etherStatsPkts512to1023Octets defined in
266RFC 2819. This statistic is the total number of packets received that were
267between 512 and 1023 octets in length inclusive.
268
269"rx_1024_1518_bytes" is equivalent to etherStatsPkts1024to1518Octets define
270in RFC 2819. This statistic is the total number of packets received that were
271between 1024 and 1518 octets in length inclusive.
272
273"rx_gte_1519_bytes" is a statistic defined specific to the behavior of the
274Altera TSE. This statistics counts the number of received good and errored
275frames between the length of 1519 and the maximum frame length configured
276in the frm_length register. See the Altera TSE User Guide for More details.
277
278"rx_jabbers" is equivalent to etherStatsJabbers defined in RFC 2819. This
279statistic is the total number of packets received that were longer than 1518
280octets, and had either a bad CRC with an integral number of octets (CRC Error)
281or a bad CRC with a non-integral number of octets (Alignment Error).
282
283"rx_runts" is equivalent to etherStatsFragments defined in RFC 2819. This
284statistic is the total number of packets received that were less than 64 octets
285in length and had either a bad CRC with an integral number of octets (CRC
286error) or a bad CRC with a non-integral number of octets (Alignment Error).
287