Out-of-line __intcall and __farcall; better detection mechanism for CM#2

4 files changed, 44 insertions, 24 deletions

diff --git a/com32/include/com32.h b/com32/include/com32.h
index 91799f6b..29656e47 100644
--- a/com32/include/com32.h
+++ b/com32/include/com32.h
@@ -77,20 +77,11 @@ extern struct com32_sys_args {
 } __com32;
 
 /*
- * System call macros
+ * System call wrapper functions
  */
-static inline void
-__intcall(uint8_t __i, const com32sys_t *__sr, com32sys_t *__dr)
-{
-  __com32.cs_intcall(__i, __sr, __dr);
-}
-
-static inline void
-__farcall(uint16_t __es, uint16_t __eo,
-	  const com32sys_t *__sr, com32sys_t *__dr)
-{
-  __com32.cs_farcall((__es << 16) + __eo, __sr, __dr);
-}
+void __intcall(uint8_t __i, const com32sys_t *__sr, com32sys_t *__dr);
+void __farcall(uint16_t __es, uint16_t __eo,
+	       const com32sys_t *__sr, com32sys_t *__dr);
 
 /*
  * These functions convert between linear pointers in the range
diff --git a/com32/include/sys/pci.h b/com32/include/sys/pci.h
index 5f530608..f1c1eb55 100644
--- a/com32/include/sys/pci.h
+++ b/com32/include/sys/pci.h
@@ -14,13 +14,14 @@ static inline pciaddr_t pci_mkaddr(uint32_t bus, uint32_t dev,
 }
 
 enum pci_config_type {
+  PCI_CFG_NONE          = -1,	/* badness */
   PCI_CFG_AUTO		= 0,	/* autodetect */
   PCI_CFG_TYPE1		= 1,
   PCI_CFG_TYPE2		= 2,
   PCI_CFG_BIOS          = 3,
 };
 
-void pci_set_config_type(enum pci_config_type);
+enum pci_config_type pci_set_config_type(enum pci_config_type);
 
 uint8_t pci_readb(pciaddr_t);
 uint16_t pci_readw(pciaddr_t);
diff --git a/com32/lib/Makefile b/com32/lib/Makefile
index 82faa553..af64950b 100644
--- a/com32/lib/Makefile
+++ b/com32/lib/Makefile
@@ -23,6 +23,7 @@ LIBOBJS = \
 	libgcc/__muldi3.o libgcc/__udivmoddi4.o libgcc/__umoddi3.o	\
 	libgcc/__divdi3.o libgcc/__moddi3.o 				\
 	\
+	sys/intcall.o sys/farcall.o					\
 	sys/entry.o sys/exit.o sys/argv.o sys/times.o sys/idle.o	\
 	sys/fileinfo.o sys/opendev.o sys/read.o sys/write.o sys/ftell.o \
 	sys/close.o sys/open.o sys/fileread.o sys/fileclose.o		\
diff --git a/com32/lib/pci/cfgtype.c b/com32/lib/pci/cfgtype.c
index e2ed6400..0fdc81e7 100644
--- a/com32/lib/pci/cfgtype.c
+++ b/com32/lib/pci/cfgtype.c
@@ -4,9 +4,8 @@
 
 enum pci_config_type __pci_cfg_type;
 
-void pci_set_config_type(enum pci_config_type type)
+int pci_set_config_type(enum pci_config_type type)
 {
-  uint32_t oldcf8;
   static const com32sys_t ireg = {
     .eax.l    = 0xb101,
     .edi.l    = 0,
@@ -15,26 +14,54 @@ void pci_set_config_type(enum pci_config_type type)
   com32sys_t oreg;
 
   if ( type == PCI_CFG_AUTO ) {
+    type = PCI_CFG_NONE;
+
     /* Try to detect PCI BIOS */
     __intcall(0x1a, &ireg, &oreg);
 
     if ( !(oreg.eflags.l & EFLAGS_CF) &&
 	 oreg.eax.b[1] == 0 && oreg.edx.l == 0x20494250 ) {
-      /* Use CM#1 if it is present, otherwise BIOS calls. CM#2 is evil. */
-      type = (oreg.eax.b[0] & 1) ? PCI_CFG_TYPE1 : PCI_CFG_BIOS;
+      /* PCI BIOS present.  Use direct access if we know how to do it. */
+      if ( oreg.eax.b[0] & 1 )
+	type = PCI_CFG_TYPE1;
+      else if ( oreg.eax.b[0] & 2 )
+	type = PCI_CFG_TYPE2;
+      else
+	type = PCI_CFG_BIOS;
     } else {
       /* Try to detect CM #1 */
+      uint32_t oldcf8, newcf8;
+      
       cli();
+      outb(1, 0xcfb);		/* Linux does this for some reason? */
       oldcf8 = inl(0xcf8);
-      outl(~0, 0xcf8);
-      if ( inl(0xcf8) == pci_mkaddr(255,31,7,252) )
-	type = PCI_CFG_TYPE1;
-      else
-	type = PCI_CFG_TYPE2;	/* ... it better be ... */
+      outl(0x80000000, 0xcf8);
+      newcf8 = inl(0xcf8);
       outl(oldcf8, 0xcf8);
       sti();
+
+      if ( newcf8 == 0x80000000 )
+	type = PCI_CFG_TYPE1;
+      else {
+	uint8_t oldcf8, oldcfa;
+	/* Try to detect CM#2 */
+	cli();
+	outb(0, 0xcfb);		/* Linux does this for some reason? */
+	oldcf8 = inb(0xcf8);
+	outb(0, 0xcf8);
+	oldcfa = inb(0xcfa);
+	outb(0, 0xcfa);
+	
+	if ( inb(0xcf8) == 0 && inb(0xcfa) == 0 )
+	  type = PCI_CFG_TYPE2;
+
+	outb(oldcf8, 0xcf8);
+	outb(oldcfa, 0xcfa);
+	sti();
+      }
     }
   }
 
-  __pci_cfg_type = type;
+  return (__pci_cfg_type = type);
 }
+