svn commit: r318208 - stable/10/sys/amd64/pci

[Sepherosa Ziehau]

Author: sephe
Date: Fri May 12 03:44:20 2017
New Revision: 318208
URL: https://svnweb.freebsd.org/changeset/base/318208

Log:
  MFC 317786
  
      pcicfg: Fix direct calls of pci_cfg{read,write} on systems w/o PCI host bridge.
  
      Reported by:    dexuan@
      Reviewed by:    jhb@
      Sponsored by:   Microsoft
      Differential Revision: https://reviews.freebsd.org/D10564

Modified:
  stable/10/sys/amd64/pci/pci_cfgreg.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/amd64/pci/pci_cfgreg.c
==============================================================================
--- stable/10/sys/amd64/pci/pci_cfgreg.c	Fri May 12 03:06:45 2017	(r318207)
+++ stable/10/sys/amd64/pci/pci_cfgreg.c	Fri May 12 03:44:20 2017	(r318208)
@@ -64,6 +64,7 @@ static vm_offset_t pcie_base;
 static int pcie_minbus, pcie_maxbus;
 static uint32_t pcie_badslots;
 static struct mtx pcicfg_mtx;
+MTX_SYSINIT(pcicfg_mtx, &pcicfg_mtx, "pcicfg_mtx", MTX_SPIN);
 static int mcfg_enable = 1;
 TUNABLE_INT("hw.pci.mcfg", &mcfg_enable);
 SYSCTL_INT(_hw_pci, OID_AUTO, mcfg, CTLFLAG_RDTUN, &mcfg_enable, 0,
@@ -75,15 +76,9 @@ SYSCTL_INT(_hw_pci, OID_AUTO, mcfg, CTLF
 int
 pci_cfgregopen(void)
 {
-	static int once = 0;
 	uint64_t pciebar;
 	uint16_t did, vid;
 
-	if (!once) {
-		mtx_init(&pcicfg_mtx, "pcicfg", NULL, MTX_SPIN);
-		once = 1;
-	}
-
 	if (cfgmech != CFGMECH_NONE)
 		return (1);
 	cfgmech = CFGMECH_1;
@@ -139,6 +134,9 @@ pci_cfgregread(int bus, int slot, int fu
 {
 	uint32_t line;
 
+	if (cfgmech == CFGMECH_NONE)
+		return (0xffffffff);
+
 	/*
 	 * Some BIOS writers seem to want to ignore the spec and put
 	 * 0 in the intline rather than 255 to indicate none.  Some use
@@ -163,6 +161,9 @@ void
 pci_cfgregwrite(int bus, int slot, int func, int reg, u_int32_t data, int bytes)
 {
 
+	if (cfgmech == CFGMECH_NONE)
+		return;
+
 	if (cfgmech == CFGMECH_PCIE &&
 	    (bus >= pcie_minbus && bus <= pcie_maxbus) &&
 	    (bus != 0 || !(1 << slot & pcie_badslots)))