| Message ID | 20220921024940.2128-1-muhammad.husaini.zulkifli@intel.com |
|---|---|
| State | Accepted |
| Delegated to: | Anthony Nguyen |
| Headers | show |
| Series | [v3] igc: Correct the launchtime offset | expand |
On 9/21/2022 05:49, Muhammad Husaini Zulkifli wrote: > 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> > --- > drivers/net/ethernet/intel/igc/igc_defines.h | 9 ++++++ > drivers/net/ethernet/intel/igc/igc_main.c | 6 ++++ > drivers/net/ethernet/intel/igc/igc_regs.h | 1 + > drivers/net/ethernet/intel/igc/igc_tsn.c | 30 ++++++++++++++++++++ > drivers/net/ethernet/intel/igc/igc_tsn.h | 1 + > 5 files changed, 47 insertions(+) > > diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h b/drivers/net/ethernet/intel/igc/igc_defines.h > index 4f9d7f013a95..f7311aeb293b 100644 > --- a/drivers/net/ethernet/intel/igc/igc_defines.h > +++ b/drivers/net/ethernet/intel/igc/igc_defines.h > @@ -400,6 +400,15 @@ > #define IGC_DTXMXPKTSZ_TSN 0x19 /* 1600 bytes of max TX DMA packet size */ > #define IGC_DTXMXPKTSZ_DEFAULT 0x98 /* 9728-byte Jumbo frames */ > > +/* Transmit Scheduling Latency */ > +/* Latency between transmission scheduling (LaunchTime) and the time > + * the packet is transmitted to the network in nanosecond. > + */ > +#define IGC_TXOFFSET_SPEED_10 0x000034BC > +#define IGC_TXOFFSET_SPEED_100 0x00000578 > +#define IGC_TXOFFSET_SPEED_1000 0x0000012C > +#define IGC_TXOFFSET_SPEED_2500 0x00000578 > + > /* Time Sync Interrupt Causes */ > #define IGC_TSICR_SYS_WRAP BIT(0) /* SYSTIM Wrap around. */ > #define IGC_TSICR_TXTS BIT(1) /* Transmit Timestamp. */ > diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c > index bf6c461e1a2a..97b9edb5153e 100644 > --- a/drivers/net/ethernet/intel/igc/igc_main.c > +++ b/drivers/net/ethernet/intel/igc/igc_main.c > @@ -5382,6 +5382,12 @@ static void igc_watchdog_task(struct work_struct *work) > break; > } > > + /* Once the launch time has been set on the wire, there is a delay > + * before the link speed can be determined based on link-up activity. > + * Write into the register as soon as we know the correct link speed. > + */ > + igc_tsn_adjust_txtime_offset(adapter); > + > if (adapter->link_speed != SPEED_1000) > goto no_wait; > > diff --git a/drivers/net/ethernet/intel/igc/igc_regs.h b/drivers/net/ethernet/intel/igc/igc_regs.h > index c0d8214148d1..01c86d36856d 100644 > --- a/drivers/net/ethernet/intel/igc/igc_regs.h > +++ b/drivers/net/ethernet/intel/igc/igc_regs.h > @@ -224,6 +224,7 @@ > /* Transmit Scheduling Registers */ > #define IGC_TQAVCTRL 0x3570 > #define IGC_TXQCTL(_n) (0x3344 + 0x4 * (_n)) > +#define IGC_GTXOFFSET 0x3310 > #define IGC_BASET_L 0x3314 > #define IGC_BASET_H 0x3318 > #define IGC_QBVCYCLET 0x331C > diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.c b/drivers/net/ethernet/intel/igc/igc_tsn.c > index 0fce22de2ab8..f975ed807da1 100644 > --- a/drivers/net/ethernet/intel/igc/igc_tsn.c > +++ b/drivers/net/ethernet/intel/igc/igc_tsn.c > @@ -48,6 +48,35 @@ static unsigned int igc_tsn_new_flags(struct igc_adapter *adapter) > return new_flags; > } > > +void igc_tsn_adjust_txtime_offset(struct igc_adapter *adapter) > +{ > + struct igc_hw *hw = &adapter->hw; > + u16 txoffset; > + > + if (!is_any_launchtime(adapter)) > + return; > + > + switch (adapter->link_speed) { > + case SPEED_10: > + txoffset = IGC_TXOFFSET_SPEED_10; > + break; > + case SPEED_100: > + txoffset = IGC_TXOFFSET_SPEED_100; > + break; > + case SPEED_1000: > + txoffset = IGC_TXOFFSET_SPEED_1000; > + break; > + case SPEED_2500: > + txoffset = IGC_TXOFFSET_SPEED_2500; > + break; > + default: > + txoffset = 0; > + break; > + } > + > + wr32(IGC_GTXOFFSET, txoffset); > +} > + > /* Returns the TSN specific registers to their default values after > * the adapter is reset. > */ > @@ -57,6 +86,7 @@ static int igc_tsn_disable_offload(struct igc_adapter *adapter) > u32 tqavctrl; > int i; > > + wr32(IGC_GTXOFFSET, 0); > wr32(IGC_TXPBS, I225_TXPBSIZE_DEFAULT); > wr32(IGC_DTXMXPKTSZ, IGC_DTXMXPKTSZ_DEFAULT); > > diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.h b/drivers/net/ethernet/intel/igc/igc_tsn.h > index 1512307f5a52..b53e6af560b7 100644 > --- a/drivers/net/ethernet/intel/igc/igc_tsn.h > +++ b/drivers/net/ethernet/intel/igc/igc_tsn.h > @@ -6,5 +6,6 @@ > > int igc_tsn_offload_apply(struct igc_adapter *adapter); > int igc_tsn_reset(struct igc_adapter *adapter); > +void igc_tsn_adjust_txtime_offset(struct igc_adapter *adapter); > > #endif /* _IGC_BASE_H */ Acked-by: Sasha Neftin <sasha.neftin@intel.com>
Dear Muhammad, One small nit. Am 21.09.22 um 04:49 schrieb Muhammad Husaini Zulkifli: […] > Test Setup: > > Talker : Use l2_tai.c to generate the launchtime into packet payload. I’d remove the space before the colon, but not important enough to send v4. > 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> Thank you for improving the commit message. Acked-by: Paul Menzel <pmenzel@molgen.mpg.de> Kind regards, Paul
Hi, > -----Original Message----- > From: Paul Menzel <pmenzel@molgen.mpg.de> > Sent: Wednesday, 21 September, 2022 4:34 PM > To: Zulkifli, Muhammad Husaini <muhammad.husaini.zulkifli@intel.com> > Cc: Gomes, Vinicius <vinicius.gomes@intel.com>; intel-wired- > lan@osuosl.org > Subject: Re: [PATCH v3] igc: Correct the launchtime offset > > Dear Muhammad, > > > One small nit. > > Am 21.09.22 um 04:49 schrieb Muhammad Husaini Zulkifli: > > […] > > > Test Setup: > > > > Talker : Use l2_tai.c to generate the launchtime into packet payload. > > I’d remove the space before the colon, but not important enough to send v4. > > > 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> > > Thank you for improving the commit message. > > Acked-by: Paul Menzel <pmenzel@molgen.mpg.de> Thanks Paul! > > > Kind regards, > > Paul
On 9/21/2022 05:49, Muhammad Husaini Zulkifli wrote: > 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> > --- > drivers/net/ethernet/intel/igc/igc_defines.h | 9 ++++++ > drivers/net/ethernet/intel/igc/igc_main.c | 6 ++++ > drivers/net/ethernet/intel/igc/igc_regs.h | 1 + > drivers/net/ethernet/intel/igc/igc_tsn.c | 30 ++++++++++++++++++++ > drivers/net/ethernet/intel/igc/igc_tsn.h | 1 + > 5 files changed, 47 insertions(+) Tested-by: Naama Meir <naamax.meir@linux.intel.com>
diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h b/drivers/net/ethernet/intel/igc/igc_defines.h index 4f9d7f013a95..f7311aeb293b 100644 --- a/drivers/net/ethernet/intel/igc/igc_defines.h +++ b/drivers/net/ethernet/intel/igc/igc_defines.h @@ -400,6 +400,15 @@ #define IGC_DTXMXPKTSZ_TSN 0x19 /* 1600 bytes of max TX DMA packet size */ #define IGC_DTXMXPKTSZ_DEFAULT 0x98 /* 9728-byte Jumbo frames */ +/* Transmit Scheduling Latency */ +/* Latency between transmission scheduling (LaunchTime) and the time + * the packet is transmitted to the network in nanosecond. + */ +#define IGC_TXOFFSET_SPEED_10 0x000034BC +#define IGC_TXOFFSET_SPEED_100 0x00000578 +#define IGC_TXOFFSET_SPEED_1000 0x0000012C +#define IGC_TXOFFSET_SPEED_2500 0x00000578 + /* Time Sync Interrupt Causes */ #define IGC_TSICR_SYS_WRAP BIT(0) /* SYSTIM Wrap around. */ #define IGC_TSICR_TXTS BIT(1) /* Transmit Timestamp. */ diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c index bf6c461e1a2a..97b9edb5153e 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -5382,6 +5382,12 @@ static void igc_watchdog_task(struct work_struct *work) break; } + /* Once the launch time has been set on the wire, there is a delay + * before the link speed can be determined based on link-up activity. + * Write into the register as soon as we know the correct link speed. + */ + igc_tsn_adjust_txtime_offset(adapter); + if (adapter->link_speed != SPEED_1000) goto no_wait; diff --git a/drivers/net/ethernet/intel/igc/igc_regs.h b/drivers/net/ethernet/intel/igc/igc_regs.h index c0d8214148d1..01c86d36856d 100644 --- a/drivers/net/ethernet/intel/igc/igc_regs.h +++ b/drivers/net/ethernet/intel/igc/igc_regs.h @@ -224,6 +224,7 @@ /* Transmit Scheduling Registers */ #define IGC_TQAVCTRL 0x3570 #define IGC_TXQCTL(_n) (0x3344 + 0x4 * (_n)) +#define IGC_GTXOFFSET 0x3310 #define IGC_BASET_L 0x3314 #define IGC_BASET_H 0x3318 #define IGC_QBVCYCLET 0x331C diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.c b/drivers/net/ethernet/intel/igc/igc_tsn.c index 0fce22de2ab8..f975ed807da1 100644 --- a/drivers/net/ethernet/intel/igc/igc_tsn.c +++ b/drivers/net/ethernet/intel/igc/igc_tsn.c @@ -48,6 +48,35 @@ static unsigned int igc_tsn_new_flags(struct igc_adapter *adapter) return new_flags; } +void igc_tsn_adjust_txtime_offset(struct igc_adapter *adapter) +{ + struct igc_hw *hw = &adapter->hw; + u16 txoffset; + + if (!is_any_launchtime(adapter)) + return; + + switch (adapter->link_speed) { + case SPEED_10: + txoffset = IGC_TXOFFSET_SPEED_10; + break; + case SPEED_100: + txoffset = IGC_TXOFFSET_SPEED_100; + break; + case SPEED_1000: + txoffset = IGC_TXOFFSET_SPEED_1000; + break; + case SPEED_2500: + txoffset = IGC_TXOFFSET_SPEED_2500; + break; + default: + txoffset = 0; + break; + } + + wr32(IGC_GTXOFFSET, txoffset); +} + /* Returns the TSN specific registers to their default values after * the adapter is reset. */ @@ -57,6 +86,7 @@ static int igc_tsn_disable_offload(struct igc_adapter *adapter) u32 tqavctrl; int i; + wr32(IGC_GTXOFFSET, 0); wr32(IGC_TXPBS, I225_TXPBSIZE_DEFAULT); wr32(IGC_DTXMXPKTSZ, IGC_DTXMXPKTSZ_DEFAULT); diff --git a/drivers/net/ethernet/intel/igc/igc_tsn.h b/drivers/net/ethernet/intel/igc/igc_tsn.h index 1512307f5a52..b53e6af560b7 100644 --- a/drivers/net/ethernet/intel/igc/igc_tsn.h +++ b/drivers/net/ethernet/intel/igc/igc_tsn.h @@ -6,5 +6,6 @@ int igc_tsn_offload_apply(struct igc_adapter *adapter); int igc_tsn_reset(struct igc_adapter *adapter); +void igc_tsn_adjust_txtime_offset(struct igc_adapter *adapter); #endif /* _IGC_BASE_H */