FAILED: patch "[PATCH] PCI: Lengthen reset delay for VideoPropulsion Torrent QN16e" failed to apply to 5.4-stable tree

The patch below does not apply to the 5.4-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 <[email protected]>.

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-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x c9260693aa0c1e029ed23693cfd4d7814eee6624
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2023112200-barcode-wasp-98d7@gregkh' --subject-prefix 'PATCH 5.4.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")
5459c0b70467 ("PCI/DPC: Quirk PIO log size for certain Intel Root Ports")
3cc30140dbe2 ("Merge tag 'pci-v5.19-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From c9260693aa0c1e029ed23693cfd4d7814eee6624 Mon Sep 17 00:00:00 2001
From: Lukas Wunner <[email protected]>
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.

index eeec1d6f9023..91a15d79c7c4 100644
@@ -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);