Artem Bityutskiy cd502a7f7c igb: add RR2DCDELAY to ethtool registers dump ... This patch adds the RR2DCDELAY register to the ethtool registers dump. RR2DCDELAY exists on I210 and I211 Intel Gigabit Ethernet chips and it stands for "Read Request To Data Completion Delay". Here is how this register is described in the I210 datasheet: "This field captures the maximum PCIe split time in 16 ns units, which is the maximum delay between the read request to the first data completion. This is giving an estimation of the PCIe round trip time." In other words, whenever I210 reads from the host memory (e.g., fetches a descriptor from the ring), the chip measures every PCI DMA read transaction and captures the maximum value. So it ends up containing the longest DMA transaction time. This register is very useful for troubleshooting and research purposes. If you are dealing with time-sensitive networks, this register can help you get an idea of your "I210-to-ring" latency. This helps answering questions like "should I have PCIe ASPM enabled?" or "should I enable deep C-states?" on my system. It is safe to read this register at any point, reading it has no effect on the I210 chip functionality. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>		2019-06-28 16:00:06 -07:00
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e1000	e1000: Use dma_wmb() instead of wmb() before doorbell writes	2019-06-28 15:59:43 -07:00
e1000e	e1000e: Reduce boot time by tightening sleep ranges	2019-06-28 15:59:52 -07:00
fm10k
i40e	i40e/i40e_virtchnl_pf: Use struct_size() in kzalloc()	2019-06-26 09:18:54 -07:00
iavf	iavf: Fix up debug print macro	2019-06-28 15:59:56 -07:00
ice	ice: Use struct_size() helper	2019-06-28 14:54:11 -07:00
igb	igb: add RR2DCDELAY to ethtool registers dump	2019-06-28 16:00:06 -07:00
igbvf
igc
ixgb
ixgbe	ixgbe: fix potential u32 overflow on shift	2019-06-28 15:59:38 -07:00
ixgbevf
e100.c
Kconfig
Makefile