- Add support for PAE and more than 4 gigs of ram on x86, dependent on the

  kernel opition 'options PAE'.  This will only work with device drivers which
  either use busdma, or are able to handle 64 bit physical addresses.

Thanks to Lanny Baron from FreeBSD Systems for the loan of a test machine
with 6 gigs of ram.

Sponsored by:	DARPA, Network Associates Laboratories, FreeBSD Systems

3 files changed, 74 insertions, 6 deletions

diff --git a/sys/amd64/include/bus_amd64.h b/sys/amd64/include/bus_amd64.h
index 20d21ec..e1f6e8e 100644
--- a/sys/amd64/include/bus_amd64.h
+++ b/sys/amd64/include/bus_amd64.h
@@ -92,15 +92,23 @@
 /*
  * Bus address and size types
  */
-typedef u_int bus_addr_t;
-typedef u_int bus_size_t;
+#ifdef PAE
+typedef uint64_t bus_addr_t;
+#else
+typedef uint32_t bus_addr_t;
+#endif
+typedef uint32_t bus_size_t;
 
 #define BUS_SPACE_MAXSIZE_24BIT	0xFFFFFF
 #define BUS_SPACE_MAXSIZE_32BIT 0xFFFFFFFF
 #define BUS_SPACE_MAXSIZE	0xFFFFFFFF
 #define BUS_SPACE_MAXADDR_24BIT	0xFFFFFF
 #define BUS_SPACE_MAXADDR_32BIT 0xFFFFFFFF
+#ifdef PAE
+#define BUS_SPACE_MAXADDR	0xFFFFFFFFFFFFFFFFULL
+#else
 #define BUS_SPACE_MAXADDR	0xFFFFFFFF
+#endif
 
 #define BUS_SPACE_UNRESTRICTED	(~0)
 
diff --git a/sys/amd64/include/bus_at386.h b/sys/amd64/include/bus_at386.h
index 20d21ec..e1f6e8e 100644
--- a/sys/amd64/include/bus_at386.h
+++ b/sys/amd64/include/bus_at386.h
@@ -92,15 +92,23 @@
 /*
  * Bus address and size types
  */
-typedef u_int bus_addr_t;
-typedef u_int bus_size_t;
+#ifdef PAE
+typedef uint64_t bus_addr_t;
+#else
+typedef uint32_t bus_addr_t;
+#endif
+typedef uint32_t bus_size_t;
 
 #define BUS_SPACE_MAXSIZE_24BIT	0xFFFFFF
 #define BUS_SPACE_MAXSIZE_32BIT 0xFFFFFFFF
 #define BUS_SPACE_MAXSIZE	0xFFFFFFFF
 #define BUS_SPACE_MAXADDR_24BIT	0xFFFFFF
 #define BUS_SPACE_MAXADDR_32BIT 0xFFFFFFFF
+#ifdef PAE
+#define BUS_SPACE_MAXADDR	0xFFFFFFFFFFFFFFFFULL
+#else
 #define BUS_SPACE_MAXADDR	0xFFFFFFFF
+#endif
 
 #define BUS_SPACE_UNRESTRICTED	(~0)
 
diff --git a/sys/amd64/include/pmap.h b/sys/amd64/include/pmap.h
index d7f0f66..8fcf2cb 100644
--- a/sys/amd64/include/pmap.h
+++ b/sys/amd64/include/pmap.h
@@ -88,8 +88,12 @@
  * This **MUST** be a multiple of 4 (eg: 252, 256, 260, etc).
  */
 #ifndef KVA_PAGES
+#ifdef PAE
+#define KVA_PAGES	512
+#else
 #define KVA_PAGES	256
 #endif
+#endif
 
 /*
  * Pte related macros
@@ -97,8 +101,12 @@
 #define VADDR(pdi, pti) ((vm_offset_t)(((pdi)<<PDRSHIFT)|((pti)<<PAGE_SHIFT)))
 
 #ifndef NKPT
+#ifdef PAE
+#define	NKPT		120	/* actual number of kernel page tables */
+#else
 #define	NKPT		30	/* actual number of kernel page tables */
 #endif
+#endif
 #ifndef NKPDE
 #ifdef SMP
 #define NKPDE	(KVA_PAGES - (NPGPTD + 1)) /* number of page tables/pde's */
@@ -134,12 +142,25 @@
 
 #include <sys/queue.h>
 
-typedef u_int32_t pd_entry_t;
-typedef u_int32_t pt_entry_t;
+#ifdef PAE
+
+typedef uint64_t pdpt_entry_t;
+typedef uint64_t pd_entry_t;
+typedef uint64_t pt_entry_t;
+
+#define	PTESHIFT	(3)
+#define	PDESHIFT	(3)
+
+#else
+
+typedef uint32_t pd_entry_t;
+typedef uint32_t pt_entry_t;
 
 #define	PTESHIFT	(2)
 #define	PDESHIFT	(2)
 
+#endif
+
 /*
  * Address of current and alternate address space page table maps
  * and directories.
@@ -149,6 +170,9 @@ extern pt_entry_t PTmap[], APTmap[];
 extern pd_entry_t PTD[], APTD[];
 extern pd_entry_t PTDpde[], APTDpde[];
 
+#ifdef PAE
+extern pdpt_entry_t *IdlePDPT;
+#endif
 extern pd_entry_t *IdlePTD;	/* physical address of "Idle" state directory */
 #endif
 
@@ -183,6 +207,30 @@ pmap_kextract(vm_offset_t va)
 }
 
 #define	vtophys(va)	pmap_kextract(((vm_offset_t) (va)))
+
+#ifdef PAE
+
+static __inline pt_entry_t
+pte_load_clear(pt_entry_t *pte)
+{
+	pt_entry_t r;
+
+	r = *pte;
+	__asm __volatile(
+	    "1:\n"
+	    "\tcmpxchg8b %1\n"
+	    "\tjnz 1b"
+	    : "+A" (r)
+	    : "m" (*pte), "b" (0), "c" (0));
+	return (r);
+}
+
+#else
+
+#define	pte_load_clear(pte)	atomic_readandclear_int(pte)
+
+#endif
+
 #endif
 
 /*
@@ -202,6 +250,10 @@ struct pmap {
 	int			pm_active;	/* active on cpus */
 	struct pmap_statistics	pm_stats;	/* pmap statistics */
 	LIST_ENTRY(pmap) 	pm_list;	/* List of all pmaps */
+#ifdef PAE
+	pdpt_entry_t		*pm_pdpt;	/* KVA of page director pointer
+						   table */
+#endif
 };
 
 #define	pmap_page_is_mapped(m)	(!TAILQ_EMPTY(&(m)->md.pv_list))