From: Martin Mares <mj@ucw.cz>
Date: Sat, 17 Mar 2018 15:28:15 +0000 (+0100)
Subject: Introduced an explicit probe sequence
X-Git-Tag: v3.6.0~21
X-Git-Url: http://git.ipfire.org/?p=thirdparty%2Fpciutils.git;a=commitdiff_plain;h=59cfe93d27db4603f5149351b9eb5d90a14f55a9

Introduced an explicit probe sequence

Previously, the probe order was determined by the order of back-ends.
However, new back-ends must be always added at the end of the list
to maintain ABI compatibility, so they were always probed last.
---

diff --git a/lib/init.c b/lib/init.c
index c7800e0..abd4fd8 100644
--- a/lib/init.c
+++ b/lib/init.c
@@ -1,7 +1,7 @@
 /*
  *	The PCI Library -- Initialization and related things
  *
- *	Copyright (c) 1997--2008 Martin Mares <mj@ucw.cz>
+ *	Copyright (c) 1997--2018 Martin Mares <mj@ucw.cz>
  *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
@@ -64,6 +64,22 @@ static struct pci_methods *pci_methods[PCI_ACCESS_MAX] = {
 #endif
 };
 
+// If PCI_ACCESS_AUTO is selected, we probe the access methods in this order
+static int probe_sequence[] = {
+  // System-specific methods
+  PCI_ACCESS_SYS_BUS_PCI,
+  PCI_ACCESS_PROC_BUS_PCI,
+  PCI_ACCESS_FBSD_DEVICE,
+  PCI_ACCESS_AIX_DEVICE,
+  PCI_ACCESS_NBSD_LIBPCI,
+  PCI_ACCESS_OBSD_DEVICE,
+  PCI_ACCESS_DARWIN,
+  // Low-level methods poking the hardware directly
+  PCI_ACCESS_I386_TYPE1,
+  PCI_ACCESS_I386_TYPE2,
+  -1,
+};
+
 void *
 pci_malloc(struct pci_access *a, int size)
 {
@@ -193,19 +209,21 @@ pci_init_v35(struct pci_access *a)
   else
     {
       unsigned int i;
-      for (i=0; i<PCI_ACCESS_MAX; i++)
-	if (pci_methods[i])
-	  {
-	    a->debug("Trying method %d...", i);
-	    if (pci_methods[i]->detect(a))
-	      {
-		a->debug("...OK\n");
-		a->methods = pci_methods[i];
-		a->method = i;
-		break;
-	      }
-	    a->debug("...No.\n");
-	  }
+      for (i=0; probe_sequence[i] >= 0; i++)
+	{
+	  struct pci_methods *m = pci_methods[probe_sequence[i]];
+	  if (!m)
+	    continue;
+	  a->debug("Trying method %s...", m->name);
+	  if (m->detect(a))
+	    {
+	      a->debug("...OK\n");
+	      a->methods = m;
+	      a->method = probe_sequence[i];
+	      break;
+	    }
+	  a->debug("...No.\n");
+	}
       if (!a->methods)
 	a->error("Cannot find any working access method.");
     }
diff --git a/lib/pci.h b/lib/pci.h
index 81bdab3..0f96101 100644
--- a/lib/pci.h
+++ b/lib/pci.h
@@ -29,7 +29,7 @@
 struct pci_methods;
 
 enum pci_access_type {
-  /* Known access methods, remember to update access.c as well */
+  /* Known access methods, remember to update init.c as well */
   PCI_ACCESS_AUTO,			/* Autodetection */
   PCI_ACCESS_SYS_BUS_PCI,		/* Linux /sys/bus/pci */
   PCI_ACCESS_PROC_BUS_PCI,		/* Linux /proc/bus/pci */