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-rw-r--r--Documentation/PCI/pci-error-recovery.rst15
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diff --git a/Documentation/PCI/pci-error-recovery.rst b/Documentation/PCI/pci-error-recovery.rst
index 5df481ac6193..43bc4e3665b4 100644
--- a/Documentation/PCI/pci-error-recovery.rst
+++ b/Documentation/PCI/pci-error-recovery.rst
@@ -326,6 +326,21 @@ be recovered, there is nothing more that can be done; the platform
will typically report a "permanent failure" in such a case. The
device will be considered "dead" in this case.
+Drivers typically need to call pci_restore_state() after reset to
+re-initialize the device's config space registers and thereby
+bring it from D0\ :sub:`uninitialized` into D0\ :sub:`active` state
+(PCIe r7.0 sec 5.3.1.1). The PCI core invokes pci_save_state()
+on enumeration after initializing config space to ensure that a
+saved state is available for subsequent error recovery.
+Drivers which modify config space on probe may need to invoke
+pci_save_state() afterwards to record those changes for later
+error recovery. When going into system suspend, pci_save_state()
+is called for every PCI device and that state will be restored
+not only on resume, but also on any subsequent error recovery.
+In the unlikely event that the saved state recorded on suspend
+is unsuitable for error recovery, drivers should call
+pci_save_state() on resume.
+
Drivers for multi-function cards will need to coordinate among
themselves as to which driver instance will perform any "one-shot"
or global device initialization. For example, the Symbios sym53cxx2