Hi Paul, Paul Menzel <pmenzel@xxxxxxxxxxxxx> writes: > Dear Vinicius, > > > Am 05.06.21 um 02:23 schrieb Vinicius Costa Gomes: >> Enables PCIe PTM (Precision Time Measurement) support in the igc >> driver. Notifies the PCI devices that PCIe PTM should be enabled. >> >> PCIe PTM is similar protocol to PTP (Precision Time Protocol) running >> in the PCIe fabric, it allows devices to report time measurements from >> their internal clocks and the correlation with the PCIe root clock. >> >> The i225 NIC exposes some registers that expose those time >> measurements, those registers will be used, in later patches, to >> implement the PTP_SYS_OFFSET_PRECISE ioctl(). >> >> Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@xxxxxxxxx> >> --- >> drivers/net/ethernet/intel/igc/igc_main.c | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c >> index a05e6d8ec660..f23d0303e53b 100644 >> --- a/drivers/net/ethernet/intel/igc/igc_main.c >> +++ b/drivers/net/ethernet/intel/igc/igc_main.c >> @@ -12,6 +12,8 @@ >> #include <net/pkt_sched.h> >> #include <linux/bpf_trace.h> >> #include <net/xdp_sock_drv.h> >> +#include <linux/pci.h> >> + >> #include <net/ipv6.h> >> >> #include "igc.h" >> @@ -5864,6 +5866,10 @@ static int igc_probe(struct pci_dev *pdev, >> >> pci_enable_pcie_error_reporting(pdev); >> >> + err = pci_enable_ptm(pdev, NULL); >> + if (err < 0) >> + dev_err(&pdev->dev, "PTM not supported\n"); >> + > > Sorry, if I am missing something, but do all devices supported by this > driver support PTM or only the i225 NIC? In that case, it wouldn’t be an > error for a device not supporting PTM, would it? That was a very good question. I had to talk with the hardware folks. All the devices supported by the igc driver should support PTM. And just to be clear, the reason that I am not returning an error here is that PTM could not be supported by the host system (think PCI controller). > >> pci_set_master(pdev); >> >> err = -ENOMEM; >> > > > Kind regards, > > Paul Cheers, -- Vinicius
