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Author SHA1 Message Date
Faizal Rahim
6c3fc0b1c3 igc: Fix qbv tx latency by setting gtxoffset
A large tx latency issue was discovered during testing when only QBV was
enabled. The issue occurs because gtxoffset was not set when QBV is
active, it was only set when launch time is active.

The patch "igc: Correct the launchtime offset" only sets gtxoffset when
the launchtime_enable field is set by the user. Enabling launchtime_enable
ultimately sets the register IGC_TXQCTL_QUEUE_MODE_LAUNCHT (referred to as
LaunchT in the SW user manual).

Section 7.5.2.6 of the IGC i225/6 SW User Manual Rev 1.2.4 states:
"The latency between transmission scheduling (launch time) and the
time the packet is transmitted to the network is listed in Table 7-61."

However, the patch misinterprets the phrase "launch time" in that section
by assuming it specifically refers to the LaunchT register, whereas it
actually denotes the generic term for when a packet is released from the
internal buffer to the MAC transmit logic.

This launch time, as per that section, also implicitly refers to the QBV
gate open time, where a packet waits in the buffer for the QBV gate to
open. Therefore, latency applies whenever QBV is in use. TSN features such
as QBU and QAV reuse QBV, making the latency universal to TSN features.

Discussed with i226 HW owner (Shalev, Avi) and we were in agreement that
the term "launch time" used in Section 7.5.2.6 is not clear and can be
easily misinterpreted. Avi will update this section to:
"When TQAVCTRL.TRANSMIT_MODE = TSN, the latency between transmission
scheduling and the time the packet is transmitted to the network is listed
in Table 7-61."

Fix this issue by using igc_tsn_is_tx_mode_in_tsn() as a condition to
write to gtxoffset, aligning with the newly updated SW User Manual.

Tested:
1. Enrol taprio on talker board
   base-time 0
   cycle-time 1000000
   flags 0x2
   index 0 cmd S gatemask 0x1 interval1
   index 0 cmd S gatemask 0x1 interval2

   Note:
   interval1 = interval for a 64 bytes packet to go through
   interval2 = cycle-time - interval1

2. Take tcpdump on listener board

3. Use udp tai app on talker to send packets to listener

4. Check the timestamp on listener via wireshark

Test Result:
100 Mbps: 113 ~193 ns
1000 Mbps: 52 ~ 84 ns
2500 Mbps: 95 ~ 223 ns

Note that the test result is similar to the patch "igc: Correct the
launchtime offset".

Fixes: 790835fcc0 ("igc: Correct the launchtime offset")
Signed-off-by: Faizal Rahim <faizal.abdul.rahim@linux.intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Mor Bar-Gabay <morx.bar.gabay@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2024-08-07 13:30:23 -07:00
Faizal Rahim
0afeaeb5da igc: Fix reset adapter logics when tx mode change
Following the "igc: Fix TX Hang issue when QBV Gate is close" changes,
remaining issues with the reset adapter logic in igc_tsn_offload_apply()
have been observed:

1. The reset adapter logics for i225 and i226 differ, although they should
   be the same according to the guidelines in I225/6 HW Design Section
   7.5.2.1 on software initialization during tx mode changes.
2. The i225 resets adapter every time, even though tx mode doesn't change.
   This occurs solely based on the condition  igc_is_device_id_i225() when
   calling schedule_work().
3. i226 doesn't reset adapter for tsn->legacy tx mode changes. It only
   resets adapter for legacy->tsn tx mode transitions.
4. qbv_count introduced in the patch is actually not needed; in this
   context, a non-zero value of qbv_count is used to indicate if tx mode
   was unconditionally set to tsn in igc_tsn_enable_offload(). This could
   be replaced by checking the existing register
   IGC_TQAVCTRL_TRANSMIT_MODE_TSN bit.

This patch resolves all issues and enters schedule_work() to reset the
adapter only when changing tx mode. It also removes reliance on qbv_count.

qbv_count field will be removed in a future patch.

Test ran:

1. Verify reset adapter behaviour in i225/6:
   a) Enrol a new GCL
      Reset adapter observed (tx mode change legacy->tsn)
   b) Enrol a new GCL without deleting qdisc
      No reset adapter observed (tx mode remain tsn->tsn)
   c) Delete qdisc
      Reset adapter observed (tx mode change tsn->legacy)

2. Tested scenario from "igc: Fix TX Hang issue when QBV Gate is closed"
   to confirm it remains resolved.

Fixes: 175c241288 ("igc: Fix TX Hang issue when QBV Gate is closed")
Signed-off-by: Faizal Rahim <faizal.abdul.rahim@linux.intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Mor Bar-Gabay <morx.bar.gabay@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2024-08-07 13:30:23 -07:00
Faizal Rahim
f8d6acaee9 igc: Fix qbv_config_change_errors logics
When user issues these cmds:
1. Either a) or b)
   a) mqprio with hardware offload disabled
   b) taprio with txtime-assist feature enabled
2. etf
3. tc qdisc delete
4. taprio with base time in the past

At step 4, qbv_config_change_errors wrongly increased by 1.

Excerpt from IEEE 802.1Q-2018 8.6.9.3.1:
"If AdminBaseTime specifies a time in the past, and the current schedule
is running, then: Increment ConfigChangeError counter"

qbv_config_change_errors should only increase if base time is in the past
and no taprio is active. In user perspective, taprio was not active when
first triggered at step 4. However, i225/6 reuses qbv for etf, so qbv is
enabled with a dummy schedule at step 2 where it enters
igc_tsn_enable_offload() and qbv_count got incremented to 1. At step 4, it
enters igc_tsn_enable_offload() again, qbv_count is incremented to 2.
Because taprio is running, tc_setup_type is TC_SETUP_QDISC_ETF and
qbv_count > 1, qbv_config_change_errors value got incremented.

This issue happens due to reliance on qbv_count field where a non-zero
value indicates that taprio is running. But qbv_count increases
regardless if taprio is triggered by user or by other tsn feature. It does
not align with qbv_config_change_errors expectation where it is only
concerned with taprio triggered by user.

Fixing this by relocating the qbv_config_change_errors logic to
igc_save_qbv_schedule(), eliminating reliance on qbv_count and its
inaccuracies from i225/6's multiple uses of qbv feature for other TSN
features.

The new function created: igc_tsn_is_taprio_activated_by_user() uses
taprio_offload_enable field to indicate that the current running taprio
was triggered by user, instead of triggered by non-qbv feature like etf.

Fixes: ae4fe46983 ("igc: Add qbv_config_change_errors counter")
Signed-off-by: Faizal Rahim <faizal.abdul.rahim@linux.intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Mor Bar-Gabay <morx.bar.gabay@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2024-08-07 13:30:23 -07:00
Faizal Rahim
e037a26ead igc: Fix packet still tx after gate close by reducing i226 MAC retry buffer
Testing uncovered that even when the taprio gate is closed, some packets
still transmit.

According to i225/6 hardware errata [1], traffic might overflow the
planned QBV window. This happens because MAC maintains an internal buffer,
primarily for supporting half duplex retries. Therefore, even when the
gate closes, residual MAC data in the buffer may still transmit.

To mitigate this for i226, reduce the MAC's internal buffer from 192 bytes
to the recommended 88 bytes by modifying the RETX_CTL register value.

This follows guidelines from:
[1] Ethernet Controller I225/I22 Spec Update Rev 2.1 Errata Item 9:
    TSN: Packet Transmission Might Cross Qbv Window
[2] I225/6 SW User Manual Rev 1.2.4: Section 8.11.5 Retry Buffer Control

Note that the RETX_CTL register can't be used in TSN mode because half
duplex feature cannot coexist with TSN.

Test Steps:
1.  Send taprio cmd to board A:
    tc qdisc replace dev enp1s0 parent root handle 100 taprio \
    num_tc 4 \
    map 3 2 1 0 3 3 3 3 3 3 3 3 3 3 3 3 \
    queues 1@0 1@1 1@2 1@3 \
    base-time 0 \
    sched-entry S 0x07 500000 \
    sched-entry S 0x0f 500000 \
    flags 0x2 \
    txtime-delay 0

    Note that for TC3, gate should open for 500us and close for another
    500us.

3.  Take tcpdump log on Board B.

4.  Send udp packets via UDP tai app from Board A to Board B.

5.  Analyze tcpdump log via wireshark log on Board B. Ensure that the
    total time from the first to the last packet received during one cycle
    for TC3 does not exceed 500us.

Fixes: 4354621173 ("igc: Add new device ID's")
Signed-off-by: Faizal Rahim <faizal.abdul.rahim@linux.intel.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Mor Bar-Gabay <morx.bar.gabay@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2024-08-07 13:30:23 -07:00
Rodrigo Cataldo
947dfc8138 igc: Fix hicredit calculation
According to the Intel Software Manual for I225, Section 7.5.2.7,
hicredit should be multiplied by the constant link-rate value, 0x7736.

Currently, the old constant link-rate value, 0x7735, from the boards
supported on igb are being used, most likely due to a copy'n'paste, as
the rest of the logic is the same for both drivers.

Update hicredit accordingly.

Fixes: 1ab011b0bf ("igc: Add support for CBS offloading")
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Rodrigo Cataldo <rodrigo.cadore@l-acoustics.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2024-01-03 11:19:47 -08:00
Florian Kauer
8b86f10ab6 igc: No strict mode in pure launchtime/CBS offload
The flags IGC_TXQCTL_STRICT_CYCLE and IGC_TXQCTL_STRICT_END
prevent the packet transmission over slot and cycle boundaries.
This is important for taprio offload where the slots and
cycles correspond to the slots and cycles configured for the
network.

However, the Qbv offload feature of the i225 is also used for
enabling TX launchtime / ETF offload. In that case, however,
the cycle has no meaning for the network and is only used
internally to adapt the base time register after a second has
passed.

Enabling strict mode in this case would unnecessarily prevent
the transmission of certain packets (i.e. at the boundary of a
second) and thus interferes with the ETF qdisc that promises
transmission at a certain point in time.

Similar to ETF, this also applies to CBS offload that also should
not be influenced by strict mode unless taprio offload would be
enabled at the same time.

This fully reverts
commit d8f45be01d ("igc: Use strict cycles for Qbv scheduling")
but its commit message only describes what was already implemented
before that commit. The difference to a plain revert of that commit
is that it now copes with the base_time = 0 case that was fixed with
commit e17090eb24 ("igc: allow BaseTime 0 enrollment for Qbv")

In particular, enabling strict mode leads to TX hang situations
under high traffic if taprio is applied WITHOUT taprio offload
but WITH ETF offload, e.g. as in

    sudo tc qdisc replace dev enp1s0 parent root handle 100 taprio \
	    num_tc 1 \
	    map 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 \
	    queues 1@0 \
	    base-time 0 \
	    sched-entry S 01 300000 \
	    flags 0x1 \
	    txtime-delay 500000 \
	    clockid CLOCK_TAI
    sudo tc qdisc replace dev enp1s0 parent 100:1 etf \
	    clockid CLOCK_TAI \
	    delta 500000 \
	    offload \
	    skip_sock_check

and traffic generator

    sudo trafgen -i traffic.cfg -o enp1s0 --cpp -n0 -q -t1400ns

with traffic.cfg

    #define ETH_P_IP        0x0800

    {
      /* Ethernet Header */
      0x30, 0x1f, 0x9a, 0xd0, 0xf0, 0x0e,  # MAC Dest - adapt as needed
      0x24, 0x5e, 0xbe, 0x57, 0x2e, 0x36,  # MAC Src  - adapt as needed
      const16(ETH_P_IP),

      /* IPv4 Header */
      0b01000101, 0,   # IPv4 version, IHL, TOS
      const16(1028),   # IPv4 total length (UDP length + 20 bytes (IP header))
      const16(2),      # IPv4 ident
      0b01000000, 0,   # IPv4 flags, fragmentation off
      64,              # IPv4 TTL
      17,              # Protocol UDP
      csumip(14, 33),  # IPv4 checksum

      /* UDP Header */
      10,  0, 48, 1,   # IP Src - adapt as needed
      10,  0, 48, 10,  # IP Dest - adapt as needed
      const16(5555),   # UDP Src Port
      const16(6666),   # UDP Dest Port
      const16(1008),   # UDP length (UDP header 8 bytes + payload length)
      csumudp(14, 34), # UDP checksum

      /* Payload */
      fill('W', 1000),
    }

and the observed message with that is for example

 igc 0000:01:00.0 enp1s0: Detected Tx Unit Hang
   Tx Queue             <0>
   TDH                  <d0>
   TDT                  <f0>
   next_to_use          <f0>
   next_to_clean        <d0>
 buffer_info[next_to_clean]
   time_stamp           <ffff661f>
   next_to_watch        <00000000245a4efb>
   jiffies              <ffff6e48>
   desc.status          <1048000>

Fixes: d8f45be01d ("igc: Use strict cycles for Qbv scheduling")
Signed-off-by: Florian Kauer <florian.kauer@linutronix.de>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2023-07-10 08:58:16 -07:00
Florian Kauer
8046063df8 igc: Rename qbv_enable to taprio_offload_enable
In the current implementation the flags adapter->qbv_enable
and IGC_FLAG_TSN_QBV_ENABLED have a similar name, but do not
have the same meaning. The first one is used only to indicate
taprio offload (i.e. when igc_save_qbv_schedule was called),
while the second one corresponds to the Qbv mode of the hardware.
However, the second one is also used to support the TX launchtime
feature, i.e. ETF qdisc offload. This leads to situations where
adapter->qbv_enable is false, but the flag IGC_FLAG_TSN_QBV_ENABLED
is set. This is prone to confusion.

The rename should reduce this confusion. Since it is a pure
rename, it has no impact on functionality.

Fixes: e17090eb24 ("igc: allow BaseTime 0 enrollment for Qbv")
Signed-off-by: Florian Kauer <florian.kauer@linutronix.de>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2023-07-10 08:40:22 -07:00
Muhammad Husaini Zulkifli
175c241288 igc: Fix TX Hang issue when QBV Gate is closed
If a user schedules a Gate Control List (GCL) to close one of
the QBV gates while also transmitting a packet to that closed gate,
TX Hang will be happen. HW would not drop any packet when the gate
is closed and keep queuing up in HW TX FIFO until the gate is re-opened.
This patch implements the solution to drop the packet for the closed
gate.

This patch will also reset the adapter to perform SW initialization
for each 1st Gate Control List (GCL) to avoid hang.
This is due to the HW design, where changing to TSN transmit mode
requires SW initialization. Intel Discrete I225/6 transmit mode
cannot be changed when in dynamic mode according to Software User
Manual Section 7.5.2.1. Subsequent Gate Control List (GCL) operations
will proceed without a reset, as they already are in TSN Mode.

Step to reproduce:

DUT:
1) Configure GCL List with certain gate close.

BASE=$(date +%s%N)
tc qdisc replace dev $IFACE parent root handle 100 taprio \
    num_tc 4 \
    map 0 1 2 3 3 3 3 3 3 3 3 3 3 3 3 3 \
    queues 1@0 1@1 1@2 1@3 \
    base-time $BASE \
    sched-entry S 0x8 500000 \
    sched-entry S 0x4 500000 \
    flags 0x2

2) Transmit the packet to closed gate. You may use udp_tai
application to transmit UDP packet to any of the closed gate.

./udp_tai -i <interface> -P 100000 -p 90 -c 1 -t <0/1> -u 30004

Fixes: ec50a9d437 ("igc: Add support for taprio offloading")
Co-developed-by: Tan Tee Min <tee.min.tan@linux.intel.com>
Signed-off-by: Tan Tee Min <tee.min.tan@linux.intel.com>
Tested-by: Chwee Lin Choong <chwee.lin.choong@intel.com>
Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2023-07-05 10:39:48 -07:00
Muhammad Husaini Zulkifli
ed89b74d2d igc: Add condition for qbv_config_change_errors counter
Add condition to increase the qbv counter during taprio qbv
configuration only.

There might be a case when TC already been setup then user configure
the ETF/CBS qdisc and this counter will increase if no condition above.

Fixes: ae4fe46983 ("igc: Add qbv_config_change_errors counter")
Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2023-07-05 10:21:33 -07:00
Muhammad Husaini Zulkifli
ae4fe46983 igc: Add qbv_config_change_errors counter
Add ConfigChangeError(qbv_config_change_errors) when user try to set the
AdminBaseTime to past value while the current GCL is still running.

The ConfigChangeError counter should not be increased when a gate control
list is scheduled into the future.

User can use "ethtool -S <interface> | grep qbv_config_change_errors"
command to check the counter values.

Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2023-03-07 13:45:56 -08:00
Muhammad Husaini Zulkifli
1d1b4c63ba igc: Remove reset adapter task for i226 during disable tsn config
I225 have limitation when programming the BaseTime register which required
a power cycle of the controller. This limitation already lifted in I226.
This patch removes the restriction so that when user configure/remove any
TSN mode, it would not go into power cycle reset adapter.

How to test:

Schedule any gate control list configuration or delete it.

Example:

1)

BASE_TIME=$(date +%s%N)
tc qdisc replace dev $interface_name parent root handle 100 taprio \
    num_tc 4 \
    map 3 1 0 2 3 3 3 3 3 3 3 3 3 3 3 3 \
    queues 1@0 1@1 1@2 1@3 \
    base-time $BASE_TIME \
    sched-entry S 0F 1000000 \
    flags 0x2

2) tc qdisc del dev $intername_name root

Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2023-01-03 09:36:25 -08:00
Tan Tee Min
5ac1231ac1 igc: enable Qbv configuration for 2nd GCL
Make reset task only executes for i225 and Qbv disabling to allow
i226 configure for 2nd GCL without resetting the adapter.

In i226, Tx won't hang if there is a GCL is already running, so in
this case we don't need to set FutScdDis bit.

Signed-off-by: Tan Tee Min <tee.min.tan@linux.intel.com>
Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2023-01-03 09:36:17 -08:00
Muhammad Husaini Zulkifli
b8897dc54e igc: remove I226 Qbv BaseTime restriction
Remove the Qbv BaseTime restriction for I226 so that the BaseTime can be
scheduled to the future time. A new register bit of Tx Qav Control
(Bit-7: FutScdDis) was introduced to allow I226 scheduling future time as
Qbv BaseTime and not having the Tx hang timeout issue.

Besides, according to datasheet section 7.5.2.9.3.3, FutScdDis bit has to
be configured first before the cycle time and base time.

Indeed the FutScdDis bit is only active on re-configuration, thus we have
to set the BASET_L to zero and then only set it to the desired value.

Please also note that the Qbv configuration flow is moved around based on
the Qbv programming guideline that is documented in the latest datasheet.

Co-developed-by: Tan Tee Min <tee.min.tan@linux.intel.com>
Signed-off-by: Tan Tee Min <tee.min.tan@linux.intel.com>
Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2023-01-03 09:35:37 -08:00
Tan Tee Min
e17090eb24 igc: allow BaseTime 0 enrollment for Qbv
Introduce qbv_enable flag in igc_adapter struct to store the Qbv on/off.
So this allow the BaseTime to enroll with zero value.

Fixes: 61572d5f8f ("igc: Simplify TSN flags handling")
Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Signed-off-by: Tan Tee Min <tee.min.tan@linux.intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2022-12-15 13:19:49 -08:00
Vinicius Costa Gomes
d8f45be01d igc: Use strict cycles for Qbv scheduling
Configuring strict cycle mode in the controller forces more well
behaved transmissions when taprio is offloaded.

When set this strict_cycle and strict_end, transmission is not
enabled if the whole packet cannot be completed before end of
the Qbv cycle.

Fixes: 82faa9b799 ("igc: Add support for ETF offloading")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Aravindhan Gunasekaran <aravindhan.gunasekaran@intel.com>
Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2022-12-15 13:19:30 -08:00
Muhammad Husaini Zulkifli
790835fcc0 igc: Correct the launchtime offset
The launchtime offset should be corrected according to sections 7.5.2.6
Transmit Scheduling Latency of the Intel Ethernet I225/I226 Software
User Manual.

Software can compensate the latency between the transmission scheduling
and the time that packet is transmitted to the network by setting this
GTxOffset register. Without setting this register, there may be a
significant delay between the packet scheduling and the network point.

This patch helps to reduce the latency for each of the link speed.

Before:

10Mbps   : 11000 - 13800 nanosecond
100Mbps  : 1300 - 1700 nanosecond
1000Mbps : 190 - 600 nanosecond
2500Mbps : 1400 - 1700 nanosecond

After:

10Mbps   : less than 750 nanosecond
100Mbps  : less than 192 nanosecond
1000Mbps : less than 128 nanosecond
2500Mbps : less than 128 nanosecond

Test Setup:

Talker : Use l2_tai.c to generate the launchtime into packet payload.
Listener: Use timedump.c to compute the delta between packet arrival and
LaunchTime packet payload.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Acked-by: Sasha Neftin <sasha.neftin@intel.com>
Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2022-11-02 11:38:22 -07:00
Aravindhan Gunasekaran
1ab011b0bf igc: Add support for CBS offloading
Implement support for Credit-based shaper(CBS) Qdisc hardware
offload mode in the driver. There are two sets of IEEE802.1Qav
(CBS) HW logic in i225 controller and this patch supports
enabling them in the top two priority TX queues.

Driver implemented as recommended by Foxville External
Architecture Specification v0.993. Idleslope and Hi-credit are
the CBS tunable parameters for i225 NIC, programmed in TQAVCC
and TQAVHC registers respectively.

In-order for IEEE802.1Qav (CBS) algorithm to work as intended
and provide BW reservation CBS should be enabled in highest
priority queue first. If we enable CBS on any of low priority
queues, the traffic in high priority queue does not allow low
priority queue to be selected for transmission and bandwidth
reservation is not guaranteed.

Signed-off-by: Aravindhan Gunasekaran <aravindhan.gunasekaran@intel.com>
Signed-off-by: Mallikarjuna Chilakala <mallikarjuna.chilakala@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2021-08-27 09:31:09 -07:00
Vinicius Costa Gomes
61572d5f8f igc: Simplify TSN flags handling
Separates the procedure done during reset from applying a
configuration, knowing when the code is executing allow us to
separate the better what changes the hardware state from what
changes only the driver state.

Introduces a flag for bookkeeping the driver state of TSN
features. When Qav and frame-preemption is also implemented
this flag makes it easier to keep track on whether a TSN feature
driver state is enabled or not though controller state changes,
say, during a reset.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Aravindhan Gunasekaran <aravindhan.gunasekaran@intel.com>
Signed-off-by: Mallikarjuna Chilakala <mallikarjuna.chilakala@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2021-08-27 09:31:08 -07:00
Vinicius Costa Gomes
c814a2d2d4 igc: Use default cycle 'start' and 'end' values for queues
Sets default values for each queue cycle start and cycle end.
This allows some simplification in the handling of these
configurations as most TSN features in i225 require a cycle
to be configured.

In i225, cycle start and end time is required to be programmed
for CBS to work properly.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Aravindhan Gunasekaran <aravindhan.gunasekaran@intel.com>
Signed-off-by: Mallikarjuna Chilakala <mallikarjuna.chilakala@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2021-08-27 09:31:08 -07:00
Muhammad Husaini Zulkifli
62f5bbfb2a igc: Set QBVCYCLET_S to 0 for TSN Basic Scheduling
According to datasheet section 8.12.19, when there's no TSN offloading
Shadow_QbvCycle bit[29:0] must be set to zero for basic scheduling.

Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2021-07-20 16:11:36 -07:00
Vinicius Costa Gomes
82faa9b799 igc: Add support for ETF offloading
This adds support for ETF offloading for the i225 controller.

For i225, the LaunchTime feature is almost a subset of the Qbv
feature. The main change from the i210 is that the launchtime of each
packet is specified as an offset applied to the BASET register. BASET
is automatically incremented each cycle.

For i225, the approach chosen is to re-use most of the setup used for
taprio offloading. With a few changes:

 - The more or less obvious one is that when ETF is enabled, we should
 set add the expected launchtime to the (advanced) transmit
 descriptor;

 - The less obvious, is that when taprio offloading is not enabled, we
 add a dummy schedule (all queues are open all the time, with a cycle
 time of 1 second).

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Reviewed-by: Andre Guedes <andre.guedes@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2020-04-17 10:19:24 -07:00
Vinicius Costa Gomes
ec50a9d437 igc: Add support for taprio offloading
Adds support for translating taprio schedules into i225 cycles. This
will allow schedules to run in the hardware, making the schedules
enforcement more precise and saving CPU time.

Right now, the only simple schedules are allowed, complex schedules are
rejected. "simple" in this context are schedules that each HW queue is
opened and closed only once in each cycle.

Changing schedules is still not supported as well.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Reviewed-by: Andre Guedes <andre.guedes@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2020-04-17 10:19:24 -07:00