The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x c9260693aa0c1e029ed23693cfd4d7814eee6624 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023112254-work-demystify-2b7c@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
c9260693aa0c ("PCI: Lengthen reset delay for VideoPropulsion Torrent QN16e card") 26409dd04589 ("of: unittest: Add pci_dt_testdrv pci driver") ae9813db1dc5 ("PCI: Add quirks to generate device tree node for Xilinx Alveo U50") 74df14cd301a ("of: unittest: add node lifecycle tests") e87cacadebaf ("of: overlay: rename overlay source files from .dts to .dtso")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From c9260693aa0c1e029ed23693cfd4d7814eee6624 Mon Sep 17 00:00:00 2001 From: Lukas Wunner lukas@wunner.de Date: Thu, 21 Sep 2023 16:23:34 +0200 Subject: [PATCH] PCI: Lengthen reset delay for VideoPropulsion Torrent QN16e card
Commit ac91e6980563 ("PCI: Unify delay handling for reset and resume") shortened an unconditional 1 sec delay after a Secondary Bus Reset to 100 msec for PCIe (per PCIe r6.1 sec 6.6.1). The 1 sec delay is only required for Conventional PCI.
But it turns out that there are PCIe devices which require a longer delay than prescribed before first config space access after reset recovery or resume from D3cold:
Chad reports that a "VideoPropulsion Torrent QN16e" MPEG QAM Modulator "raises a PCI system error (PERR), as reported by the IPMI event log, and the hardware itself would suffer a catastrophic event, cycling the server" unless the longer delay is observed.
The card is specified to conform to PCIe r1.0 and indeed only supports Gen1 speed (2.5 GT/s) according to lspci. PCIe r1.0 sec 7.6 prescribes the same 100 msec delay as PCIe r6.1 sec 6.6.1:
To allow components to perform internal initialization, system software must wait for at least 100 ms from the end of a reset (cold/warm/hot) before it is permitted to issue Configuration Requests
The behavior of the Torrent QN16e card thus appears to be a quirk. Treat it as such and lengthen the reset delay for this specific device.
Fixes: ac91e6980563 ("PCI: Unify delay handling for reset and resume") Link: https://lore.kernel.org/r/47727e792c7f0282dc144e3ec8ce8eb6e713394e.169530451... Reported-by: Chad Schroeder CSchroeder@sonifi.com Closes: https://lore.kernel.org/linux-pci/DM6PR16MB2844903E34CAB910082DF019B1FAA@DM6... Tested-by: Chad Schroeder CSchroeder@sonifi.com Signed-off-by: Lukas Wunner lukas@wunner.de Signed-off-by: Bjorn Helgaas bhelgaas@google.com Cc: stable@vger.kernel.org # v5.4+
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index eeec1d6f9023..91a15d79c7c4 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -6188,3 +6188,15 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a31, dpc_log_size); DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_XILINX, 0x5020, of_pci_make_dev_node); DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_XILINX, 0x5021, of_pci_make_dev_node); DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_REDHAT, 0x0005, of_pci_make_dev_node); + +/* + * Devices known to require a longer delay before first config space access + * after reset recovery or resume from D3cold: + * + * VideoPropulsion (aka Genroco) Torrent QN16e MPEG QAM Modulator + */ +static void pci_fixup_d3cold_delay_1sec(struct pci_dev *pdev) +{ + pdev->d3cold_delay = 1000; +} +DECLARE_PCI_FIXUP_FINAL(0x5555, 0x0004, pci_fixup_d3cold_delay_1sec);