Changeset 408 for soft/giet_vm/giet_common/vmem.h

Timestamp:

Sep 29, 2014, 10:47:26 AM (10 years ago)

Author:

alain

Message:

Introducing a physical memory allocator (pmem.c & pmem.h files).

File:

• soft/giet_vm/giet_common/vmem.h (modified) (4 diffs)

soft/giet_vm/giet_common/vmem.h

@@ -1 +1 @@
 ///////////////////////////////////////////////////////////////////////////////////
-// File     : vm_handler.h
+// File     : vmem.h
 // Date     : 01/07/2012
 // Author   : alain greiner
 // Copyright (c) UPMC-LIP6
 ///////////////////////////////////////////////////////////////////////////////////
+// The vmem.c and vmem.h files are part ot the GIET-VM nano kernel.
+// They define  the data structures implementing the page tables,
+// and the function used for VPN to PPN translation.
+///////////////////////////////////////////////////////////////////////////////////
+// The virtual address format is 32 bits: structures in 3 fields:
+//             |  11  |  9   |   12   |
+//             | IX1  | IX2  | OFFSET |
+// - The IX1 field is the index in the first level page table
+// - The IX2 field is the index in the second level page table
+// - The |IX1|IX2\ concatenation defines the VPN (Virtual Page Number)
+///////////////////////////////////////////////////////////////////////////////////
 
-#ifndef _VM_HANDLER_H_
-#define _VM_HANDLER_H_
-
-#include <giet_config.h>
-#include <mapping_info.h>
+#ifndef _VMEM_H_
+#define _VMEM_H_
 
 /////////////////////////////////////////////////////////////////////////////////////
@@ -18 +26 @@
 #define PT1_SIZE    8192
 #define PT2_SIZE    4096
+
+#define VPN_MASK    0xFFFFF000
+#define BPN_MASK    0xFFE00000
 
 /////////////////////////////////////////////////////////////////////////////////////
@@ -51 +62 @@
 // Page table structure definition
 /////////////////////////////////////////////////////////////////////////////////////
+
 typedef struct PageTable 
 {
@@ -57 +69 @@
 } page_table_t;
 
-
-////////////////////////////////////////////////////////////////////////////////////
-// Global variable
-////////////////////////////////////////////////////////////////////////////////////
-
-extern page_table_t _iommu_ptab;
-
 ////////////////////////////////////////////////////////////////////////////////////
 // functions prototypes
 ////////////////////////////////////////////////////////////////////////////////////
 
-void _iommu_add_pte2( unsigned int ix1, 
-                      unsigned int ix2, 
-                      unsigned int ppn, 
-                      unsigned int flags );
-
-void _iommu_inval_pte2( unsigned int ix1, 
-                        unsigned int ix2 );
-
+///////////////////////////////////////////////////////////////////////////////////
+// This function makes a "vpn" to "ppn" translation, from the page table 
+// defined by the virtual address "pt". The MMU is supposed to be activated.
+// It supports both small (4 Kbytes) & big (2 Mbytes) pages.
+// It uses the address extension mechanism for physical addressing.
+// Return 0 if success. Return 1 if PTE1 or PTE2 unmapped.
+///////////////////////////////////////////////////////////////////////////////////
 unsigned int _v2p_translate( page_table_t* pt, 
                              unsigned int  vpn,