linux/drivers/net/dsa/sja1105/sja1105_tas.h

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/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2019, Vladimir Oltean <olteanv@gmail.com>
net: dsa: sja1105: Configure the Time-Aware Scheduler via tc-taprio offload This qdisc offload is the closest thing to what the SJA1105 supports in hardware for time-based egress shaping. The switch core really is built around SAE AS6802/TTEthernet (a TTTech standard) but can be made to operate similarly to IEEE 802.1Qbv with some constraints: - The gate control list is a global list for all ports. There are 8 execution threads that iterate through this global list in parallel. I don't know why 8, there are only 4 front-panel ports. - Care must be taken by the user to make sure that two execution threads never get to execute a GCL entry simultaneously. I created a O(n^4) checker for this hardware limitation, prior to accepting a taprio offload configuration as valid. - The spec says that if a GCL entry's interval is shorter than the frame length, you shouldn't send it (and end up in head-of-line blocking). Well, this switch does anyway. - The switch has no concept of ADMIN and OPER configurations. Because it's so simple, the TAS settings are loaded through the static config tables interface, so there isn't even place for any discussion about 'graceful switchover between ADMIN and OPER'. You just reset the switch and upload a new OPER config. - The switch accepts multiple time sources for the gate events. Right now I am using the standalone clock source as opposed to PTP. So the base time parameter doesn't really do much. Support for the PTP clock source will be added in a future series. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-15 05:00:02 +03:00
*/
#ifndef _SJA1105_TAS_H
#define _SJA1105_TAS_H
#include <net/pkt_sched.h>
#if IS_ENABLED(CONFIG_NET_DSA_SJA1105_TAS)
net: dsa: sja1105: Implement state machine for TAS with PTP clock source Tested using the following bash script and the tc from iproute2-next: #!/bin/bash set -e -u -o pipefail NSEC_PER_SEC="1000000000" gatemask() { local tc_list="$1" local mask=0 for tc in ${tc_list}; do mask=$((${mask} | (1 << ${tc}))) done printf "%02x" ${mask} } if ! systemctl is-active --quiet ptp4l; then echo "Please start the ptp4l service" exit fi now=$(phc_ctl /dev/ptp1 get | gawk '/clock time is/ { print $5; }') # Phase-align the base time to the start of the next second. sec=$(echo "${now}" | gawk -F. '{ print $1; }') base_time="$(((${sec} + 1) * ${NSEC_PER_SEC}))" tc qdisc add dev swp5 parent root handle 100 taprio \ num_tc 8 \ map 0 1 2 3 5 6 7 \ queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \ base-time ${base_time} \ sched-entry S $(gatemask 7) 100000 \ sched-entry S $(gatemask "0 1 2 3 4 5 6") 400000 \ clockid CLOCK_TAI flags 2 The "state machine" is a workqueue invoked after each manipulation command on the PTP clock (reset, adjust time, set time, adjust frequency) which checks over the state of the time-aware scheduler. So it is not monitored periodically, only in reaction to a PTP command typically triggered from a userspace daemon (linuxptp). Otherwise there is no reason for things to go wrong. Now that the timecounter/cyclecounter has been replaced with hardware operations on the PTP clock, the TAS Kconfig now depends upon PTP and the standalone clocksource operating mode has been removed. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-12 02:11:54 +02:00
enum sja1105_tas_state {
SJA1105_TAS_STATE_DISABLED,
SJA1105_TAS_STATE_ENABLED_NOT_RUNNING,
SJA1105_TAS_STATE_RUNNING,
};
enum sja1105_ptp_op {
SJA1105_PTP_NONE,
SJA1105_PTP_CLOCKSTEP,
SJA1105_PTP_ADJUSTFREQ,
};
net: dsa: sja1105: Configure the Time-Aware Scheduler via tc-taprio offload This qdisc offload is the closest thing to what the SJA1105 supports in hardware for time-based egress shaping. The switch core really is built around SAE AS6802/TTEthernet (a TTTech standard) but can be made to operate similarly to IEEE 802.1Qbv with some constraints: - The gate control list is a global list for all ports. There are 8 execution threads that iterate through this global list in parallel. I don't know why 8, there are only 4 front-panel ports. - Care must be taken by the user to make sure that two execution threads never get to execute a GCL entry simultaneously. I created a O(n^4) checker for this hardware limitation, prior to accepting a taprio offload configuration as valid. - The spec says that if a GCL entry's interval is shorter than the frame length, you shouldn't send it (and end up in head-of-line blocking). Well, this switch does anyway. - The switch has no concept of ADMIN and OPER configurations. Because it's so simple, the TAS settings are loaded through the static config tables interface, so there isn't even place for any discussion about 'graceful switchover between ADMIN and OPER'. You just reset the switch and upload a new OPER config. - The switch accepts multiple time sources for the gate events. Right now I am using the standalone clock source as opposed to PTP. So the base time parameter doesn't really do much. Support for the PTP clock source will be added in a future series. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-15 05:00:02 +03:00
struct sja1105_tas_data {
struct tc_taprio_qopt_offload *offload[SJA1105_NUM_PORTS];
net: dsa: sja1105: Implement state machine for TAS with PTP clock source Tested using the following bash script and the tc from iproute2-next: #!/bin/bash set -e -u -o pipefail NSEC_PER_SEC="1000000000" gatemask() { local tc_list="$1" local mask=0 for tc in ${tc_list}; do mask=$((${mask} | (1 << ${tc}))) done printf "%02x" ${mask} } if ! systemctl is-active --quiet ptp4l; then echo "Please start the ptp4l service" exit fi now=$(phc_ctl /dev/ptp1 get | gawk '/clock time is/ { print $5; }') # Phase-align the base time to the start of the next second. sec=$(echo "${now}" | gawk -F. '{ print $1; }') base_time="$(((${sec} + 1) * ${NSEC_PER_SEC}))" tc qdisc add dev swp5 parent root handle 100 taprio \ num_tc 8 \ map 0 1 2 3 5 6 7 \ queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \ base-time ${base_time} \ sched-entry S $(gatemask 7) 100000 \ sched-entry S $(gatemask "0 1 2 3 4 5 6") 400000 \ clockid CLOCK_TAI flags 2 The "state machine" is a workqueue invoked after each manipulation command on the PTP clock (reset, adjust time, set time, adjust frequency) which checks over the state of the time-aware scheduler. So it is not monitored periodically, only in reaction to a PTP command typically triggered from a userspace daemon (linuxptp). Otherwise there is no reason for things to go wrong. Now that the timecounter/cyclecounter has been replaced with hardware operations on the PTP clock, the TAS Kconfig now depends upon PTP and the standalone clocksource operating mode has been removed. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-12 02:11:54 +02:00
enum sja1105_tas_state state;
enum sja1105_ptp_op last_op;
struct work_struct tas_work;
s64 earliest_base_time;
s64 oper_base_time;
u64 max_cycle_time;
bool enabled;
net: dsa: sja1105: Configure the Time-Aware Scheduler via tc-taprio offload This qdisc offload is the closest thing to what the SJA1105 supports in hardware for time-based egress shaping. The switch core really is built around SAE AS6802/TTEthernet (a TTTech standard) but can be made to operate similarly to IEEE 802.1Qbv with some constraints: - The gate control list is a global list for all ports. There are 8 execution threads that iterate through this global list in parallel. I don't know why 8, there are only 4 front-panel ports. - Care must be taken by the user to make sure that two execution threads never get to execute a GCL entry simultaneously. I created a O(n^4) checker for this hardware limitation, prior to accepting a taprio offload configuration as valid. - The spec says that if a GCL entry's interval is shorter than the frame length, you shouldn't send it (and end up in head-of-line blocking). Well, this switch does anyway. - The switch has no concept of ADMIN and OPER configurations. Because it's so simple, the TAS settings are loaded through the static config tables interface, so there isn't even place for any discussion about 'graceful switchover between ADMIN and OPER'. You just reset the switch and upload a new OPER config. - The switch accepts multiple time sources for the gate events. Right now I am using the standalone clock source as opposed to PTP. So the base time parameter doesn't really do much. Support for the PTP clock source will be added in a future series. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-15 05:00:02 +03:00
};
int sja1105_setup_tc_taprio(struct dsa_switch *ds, int port,
struct tc_taprio_qopt_offload *admin);
void sja1105_tas_setup(struct dsa_switch *ds);
void sja1105_tas_teardown(struct dsa_switch *ds);
net: dsa: sja1105: Implement state machine for TAS with PTP clock source Tested using the following bash script and the tc from iproute2-next: #!/bin/bash set -e -u -o pipefail NSEC_PER_SEC="1000000000" gatemask() { local tc_list="$1" local mask=0 for tc in ${tc_list}; do mask=$((${mask} | (1 << ${tc}))) done printf "%02x" ${mask} } if ! systemctl is-active --quiet ptp4l; then echo "Please start the ptp4l service" exit fi now=$(phc_ctl /dev/ptp1 get | gawk '/clock time is/ { print $5; }') # Phase-align the base time to the start of the next second. sec=$(echo "${now}" | gawk -F. '{ print $1; }') base_time="$(((${sec} + 1) * ${NSEC_PER_SEC}))" tc qdisc add dev swp5 parent root handle 100 taprio \ num_tc 8 \ map 0 1 2 3 5 6 7 \ queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \ base-time ${base_time} \ sched-entry S $(gatemask 7) 100000 \ sched-entry S $(gatemask "0 1 2 3 4 5 6") 400000 \ clockid CLOCK_TAI flags 2 The "state machine" is a workqueue invoked after each manipulation command on the PTP clock (reset, adjust time, set time, adjust frequency) which checks over the state of the time-aware scheduler. So it is not monitored periodically, only in reaction to a PTP command typically triggered from a userspace daemon (linuxptp). Otherwise there is no reason for things to go wrong. Now that the timecounter/cyclecounter has been replaced with hardware operations on the PTP clock, the TAS Kconfig now depends upon PTP and the standalone clocksource operating mode has been removed. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-12 02:11:54 +02:00
void sja1105_tas_clockstep(struct dsa_switch *ds);
void sja1105_tas_adjfreq(struct dsa_switch *ds);
net: dsa: sja1105: Configure the Time-Aware Scheduler via tc-taprio offload This qdisc offload is the closest thing to what the SJA1105 supports in hardware for time-based egress shaping. The switch core really is built around SAE AS6802/TTEthernet (a TTTech standard) but can be made to operate similarly to IEEE 802.1Qbv with some constraints: - The gate control list is a global list for all ports. There are 8 execution threads that iterate through this global list in parallel. I don't know why 8, there are only 4 front-panel ports. - Care must be taken by the user to make sure that two execution threads never get to execute a GCL entry simultaneously. I created a O(n^4) checker for this hardware limitation, prior to accepting a taprio offload configuration as valid. - The spec says that if a GCL entry's interval is shorter than the frame length, you shouldn't send it (and end up in head-of-line blocking). Well, this switch does anyway. - The switch has no concept of ADMIN and OPER configurations. Because it's so simple, the TAS settings are loaded through the static config tables interface, so there isn't even place for any discussion about 'graceful switchover between ADMIN and OPER'. You just reset the switch and upload a new OPER config. - The switch accepts multiple time sources for the gate events. Right now I am using the standalone clock source as opposed to PTP. So the base time parameter doesn't really do much. Support for the PTP clock source will be added in a future series. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-15 05:00:02 +03:00
#else
/* C doesn't allow empty structures, bah! */
struct sja1105_tas_data {
u8 dummy;
};
static inline int sja1105_setup_tc_taprio(struct dsa_switch *ds, int port,
struct tc_taprio_qopt_offload *admin)
{
return -EOPNOTSUPP;
}
static inline void sja1105_tas_setup(struct dsa_switch *ds) { }
static inline void sja1105_tas_teardown(struct dsa_switch *ds) { }
net: dsa: sja1105: Implement state machine for TAS with PTP clock source Tested using the following bash script and the tc from iproute2-next: #!/bin/bash set -e -u -o pipefail NSEC_PER_SEC="1000000000" gatemask() { local tc_list="$1" local mask=0 for tc in ${tc_list}; do mask=$((${mask} | (1 << ${tc}))) done printf "%02x" ${mask} } if ! systemctl is-active --quiet ptp4l; then echo "Please start the ptp4l service" exit fi now=$(phc_ctl /dev/ptp1 get | gawk '/clock time is/ { print $5; }') # Phase-align the base time to the start of the next second. sec=$(echo "${now}" | gawk -F. '{ print $1; }') base_time="$(((${sec} + 1) * ${NSEC_PER_SEC}))" tc qdisc add dev swp5 parent root handle 100 taprio \ num_tc 8 \ map 0 1 2 3 5 6 7 \ queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \ base-time ${base_time} \ sched-entry S $(gatemask 7) 100000 \ sched-entry S $(gatemask "0 1 2 3 4 5 6") 400000 \ clockid CLOCK_TAI flags 2 The "state machine" is a workqueue invoked after each manipulation command on the PTP clock (reset, adjust time, set time, adjust frequency) which checks over the state of the time-aware scheduler. So it is not monitored periodically, only in reaction to a PTP command typically triggered from a userspace daemon (linuxptp). Otherwise there is no reason for things to go wrong. Now that the timecounter/cyclecounter has been replaced with hardware operations on the PTP clock, the TAS Kconfig now depends upon PTP and the standalone clocksource operating mode has been removed. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-12 02:11:54 +02:00
static inline void sja1105_tas_clockstep(struct dsa_switch *ds) { }
static inline void sja1105_tas_adjfreq(struct dsa_switch *ds) { }
net: dsa: sja1105: Configure the Time-Aware Scheduler via tc-taprio offload This qdisc offload is the closest thing to what the SJA1105 supports in hardware for time-based egress shaping. The switch core really is built around SAE AS6802/TTEthernet (a TTTech standard) but can be made to operate similarly to IEEE 802.1Qbv with some constraints: - The gate control list is a global list for all ports. There are 8 execution threads that iterate through this global list in parallel. I don't know why 8, there are only 4 front-panel ports. - Care must be taken by the user to make sure that two execution threads never get to execute a GCL entry simultaneously. I created a O(n^4) checker for this hardware limitation, prior to accepting a taprio offload configuration as valid. - The spec says that if a GCL entry's interval is shorter than the frame length, you shouldn't send it (and end up in head-of-line blocking). Well, this switch does anyway. - The switch has no concept of ADMIN and OPER configurations. Because it's so simple, the TAS settings are loaded through the static config tables interface, so there isn't even place for any discussion about 'graceful switchover between ADMIN and OPER'. You just reset the switch and upload a new OPER config. - The switch accepts multiple time sources for the gate events. Right now I am using the standalone clock source as opposed to PTP. So the base time parameter doesn't really do much. Support for the PTP clock source will be added in a future series. Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-15 05:00:02 +03:00
#endif /* IS_ENABLED(CONFIG_NET_DSA_SJA1105_TAS) */
#endif /* _SJA1105_TAS_H */