Hello Bjorn, On 29/03/23 22:38, Bjorn Helgaas wrote: > On Wed, Mar 29, 2023 at 08:11:25PM +0530, Raghavendra, Vignesh wrote: >> Hi Lorenzo, Bjorn, >> >> On 3/15/2023 12:38 PM, Siddharth Vadapalli wrote: >>> The Link Retraining process is initiated to account for the Gen2 defect in >>> the Cadence PCIe controller in J721E SoC. The errata corresponding to this >>> is i2085, documented at: >>> https://www.ti.com/lit/er/sprz455c/sprz455c.pdf >>> >>> The existing workaround implemented for the errata waits for the Data Link >>> initialization to complete and assumes that the link retraining process >>> at the Physical Layer has completed. However, it is possible that the >>> Physical Layer training might be ongoing as indicated by the >>> PCI_EXP_LNKSTA_LT bit in the PCI_EXP_LNKSTA register. >>> >>> Fix the existing workaround, to ensure that the Physical Layer training >>> has also completed, in addition to the Data Link initialization. >>> >>> Fixes: 4740b969aaf5 ("PCI: cadence: Retrain Link to work around Gen2 training defect") >>> Signed-off-by: Siddharth Vadapalli <s-vadapalli@xxxxxx> >>> Reviewed-by: Vignesh Raghavendra <vigneshr@xxxxxx> >>> --- >>> Changes from v1: >>> 1. Collect Reviewed-by tag from Vignesh Raghavendra. >>> 2. Rebase on next-20230315. >>> >>> v1: >>> https://lore.kernel.org/r/20230102075656.260333-1-s-vadapalli@xxxxxx >>> >>> .../controller/cadence/pcie-cadence-host.c | 27 +++++++++++++++++++ >>> 1 file changed, 27 insertions(+) >> >> Wondering do one of you be pulling this patch in? This patch was never >> picked for 6.3-rc1 merge cycle... Just want to make sure >> pcie-cadence*.c and pci-j721e.c patches have a path to reach pci tree. > > Yes, Lorenzo or Krzysztof will likely pick this up. I think Lorenzo > is out of the office this week. > > Drive-by comment: the current patch doesn't seem to give any > indication to the user when cdns_pcie_host_training_complete() times > out. Is that timeout potentially of interest to a user? Should there > be a log message there? Thank you for reviewing the patch. The return value of -ETIMEDOUT from the function cdns_pcie_host_training_complete() added by this patch will be handled similar to the -ETIMEDOUT from the cdns_pcie_host_wait_for_link() function that is already present. If cdns_pcie_host_training_complete() returns -ETIMEDOUT, it is returned to cdns_pcie_host_start_link() function which is called within cdns_pcie_host_setup() function. In the cdns_pcie_host_setup() function, there is already a dev_dbg() print for handling the case where cdns_pcie_host_wait_for_link() times out. For this reason, I felt that for both cases, the dev_dbg() print can be used to debug without the need for an extra log message. Please let me know if that's fine. Regards, Siddharth.
