svn commit: r345997 - head/sys/dev/pci

[Konstantin Belousov]

Author: kib
Date: Sun Apr  7 08:58:09 2019
New Revision: 345997
URL: https://svnweb.freebsd.org/changeset/base/345997

Log:
  Give new home to the comment from ppt_pci_reset(), explaining a nuance
  of power reset.
  
  Noted by:	soralx at cydem.org
  Sponsored by:	Mellanox Technologies
  MFC after:	12 days

Modified:
  head/sys/dev/pci/pci.c

Modified: head/sys/dev/pci/pci.c
==============================================================================
--- head/sys/dev/pci/pci.c	Sat Apr  6 23:35:23 2019	(r345996)
+++ head/sys/dev/pci/pci.c	Sun Apr  7 08:58:09 2019	(r345997)
@@ -6394,6 +6394,11 @@ pcie_flr(device_t dev, u_int max_delay, bool force)
 	return (true);
 }
 
+/*
+ * Attempt a power-management reset by cycling the device in/out of D3
+ * state.  PCI spec says we can only go into D3 state from D0 state.
+ * Transition from D[12] into D0 before going to D3 state.
+ */
 int
 pci_power_reset(device_t dev)
 {