package/kernel/linux/hotfix-fw643-reset.patch

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   2 # T2 SDE: package/*/linux/hotfix-fw643-reset.patch
   3 # Copyright (C) 2024 The T2 SDE Project
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  13
  14 diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
  15 index d797df6e5f3e..e0e4ad9e6d50 100644
  16 --- a/drivers/pci/quirks.c
  17 +++ b/drivers/pci/quirks.c
  18 @@ -3765,6 +3765,19 @@  DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x003e, quirk_no_bus_reset);
  19   */
  20  DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CAVIUM, 0xa100, quirk_no_bus_reset);
  21
  22 +/*
  23 + * Using LSI / Agere FW643 with vfio-pci will exhaust all
  24 + * pci_reset_fn_methods, the bus reset at the end causes a broken link
  25 + * only recoverable by removing power
  26 + * (power-off / suspend + rescan).
  27 + * Prevent this bus reset.
  28 + * With this change, the device can be assigned to VMs with VFIO.
  29 + * Note that it will not be reset, resulting in leaking state between VMs
  30 + * and host.
  31 + */
  32 +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATT, 0x5900, quirk_no_bus_reset);
  33 +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATT, 0x5901, quirk_no_bus_reset);
  34 +
  35  /*
  36   * Some TI KeyStone C667X devices do not support bus/hot reset.  The PCIESS
  37   * automatically disables LTSSM when Secondary Bus Reset is received and