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

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.c (modified) (4 diffs)

soft/giet_vm/giet_common/vmem.c

@@ -5 +5 @@
 // Copyright (c) UPMC-LIP6
 ///////////////////////////////////////////////////////////////////////////////////
-// The vmem.c and vmem.h files are part ot the GIET-VM nano kernel.
-// They contain the kernel data structures and functions used to dynamically
-// handle the paged virtual memory.
-///////////////////////////////////////////////////////////////////////////////////
 
 #include <utils.h>
-#include <tty_driver.h>
 #include <vmem.h>
 #include <giet_config.h>
-#include <tty_driver.h>
 
-/////////////////////////////////////////////////////////////////////////////
-//     Global variable : IOMMU page table
-/////////////////////////////////////////////////////////////////////////////
-
-__attribute__((section (".iommu"))) page_table_t _iommu_ptab;
-
-//////////////////////////////////////////////////////////////////////////////
-// _iommu_add_pte2()
-//////////////////////////////////////////////////////////////////////////////
-void _iommu_add_pte2( unsigned int ix1,
-                      unsigned int ix2,
-                      unsigned int ppn,
-                      unsigned int flags ) 
-{
-    unsigned int ptba;
-    unsigned int * pt_ppn;
-    unsigned int * pt_flags;
-
-    // get pointer on iommu page table
-    page_table_t * pt = &_iommu_ptab;
-
-    // get ptba and update PT2
-    if ((pt->pt1[ix1] & PTE_V) == 0) 
-    {
-        _printf("\n[GIET ERROR] in iommu_add_pte2() : "
-                "IOMMU PT1 entry not mapped / ix1 = %d\n", ix1 );
-        _exit();
-    }
-    else 
-    {
-        ptba = pt->pt1[ix1] << 12;
-        pt_flags = (unsigned int *) (ptba + 8 * ix2);
-        pt_ppn = (unsigned int *) (ptba + 8 * ix2 + 4);
-        *pt_flags = flags;
-        *pt_ppn = ppn;
-    }
-} // end _iommu_add_pte2()
-
-
-//////////////////////////////////////////////////////////////////////////////
-// _iommu_inval_pte2()
-//////////////////////////////////////////////////////////////////////////////
-void _iommu_inval_pte2( unsigned int ix1, 
-                        unsigned int ix2 ) 
-{
-    unsigned int ptba;
-    unsigned int * pt_flags;
-
-    // get pointer on iommu page table
-    page_table_t * pt = &_iommu_ptab;
-
-    // get ptba and inval PTE2
-    if ((pt->pt1[ix1] & PTE_V) == 0)
-    {
-        _printf("\n[GIET ERROR] in iommu_inval_pte2() "
-              "IOMMU PT1 entry not mapped / ix1 = %d\n", ix1 );
-        _exit();
-    }
-    else {
-        ptba = pt->pt1[ix1] << 12;
-        pt_flags = (unsigned int *) (ptba + 8 * ix2);
-        *pt_flags = 0;
-    }   
-} // end _iommu_inval_pte2()
-
-//////////////////////////////////////////////////////////////////////////////
-// 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 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 _v2p_translate( page_table_t*  ptab,
                              unsigned int   vpn,
                              unsigned int*  ppn,
@@ -106 +30 @@
 
     // get PTE1
-    unsigned int pte1 = pt->pt1[ix1];
+    unsigned int pte1 = ptab->pt1[ix1];
 
     // check PTE1 mapping
-    if ( (pte1 & PTE_V) == 0 )  return 1;
+    if ( (pte1 & PTE_V) == 0 )
+    {
+        _printf("\n[VMEM ERROR] _v2p_translate() : pte1 unmapped\n");
+        _exit();
+    }
 
-    // get physical addresses of pte2 (two 32 bits words)
-    ptba       = (unsigned long long) (pte1 & 0x0FFFFFFF) << 12;
-    pte2_paddr = ptba + 8*ix2;
-    pte2_lsb   = (unsigned int) pte2_paddr;
-    pte2_msb   = (unsigned int) (pte2_paddr >> 32);
+    // test big/small page
+    if ( (pte1 & PTE_T) == 0 )  // big page
+    {
+        // set return values
+        *ppn   = ((pte1 << 9) & 0x0FFFFE00) | (vpn & 0X000001FF);
+        *flags = pte1 & 0xFFC00000;
+    }
+    else                        // small page
+    {
 
-    // disable interrupts and save status register
-    _it_disable( &save_sr );
+        // get physical addresses of pte2 (two 32 bits words)
+        ptba       = (unsigned long long) (pte1 & 0x0FFFFFFF) << 12;
+        pte2_paddr = ptba + 8*ix2;
+        pte2_lsb   = (unsigned int) pte2_paddr;
+        pte2_msb   = (unsigned int) (pte2_paddr >> 32);
 
-    // gets ppn_value and flags_value, after temporary DTLB desactivation
-    asm volatile (
+        // disable interrupts and save status register
+        _it_disable( &save_sr );
+
+        // get ppn_value and flags_value, using a physical read
+        // after temporary DTLB desactivation
+        asm volatile (
                 "mfc2    $2,     $1          \n"     /* $2 <= MMU_MODE       */
                 "andi    $3,     $2,    0xb  \n"
@@ -127 +66 @@
 
                 "move    $4,     %3          \n"     /* $4 <= pte_lsb        */
-                "mtc2    %2,     $24         \n"     /* PADDR_EXT <= msb     */
+                "mtc2    %2,     $24         \n"     /* PADDR_EXT <= pte_msb */
                 "lw      %0,     0($4)       \n"     /* read flags           */ 
                 "lw      %1,     4($4)       \n"     /* read ppn             */
@@ -137 +76 @@
                 : "$2", "$3", "$4" );
 
-    // restore saved status register
-    _it_restore( &save_sr );
+        // restore saved status register
+        _it_restore( &save_sr );
 
-    // check PTE2 mapping
-    if ( (flags_value & PTE_V) == 0 )  return 1;
+        // set return values 
+        *ppn   = ppn_value   & 0x0FFFFFFF;
+        *flags = flags_value & 0xFFC00000;
 
-    // set return values 
-    *ppn   = ppn_value;
-    *flags = flags_value;
-
+        // check PTE2 mapping
+        if ( (flags_value & PTE_V) == 0 )
+        {
+            _printf("\n[VMEM ERROR] _v2p_translate() : pte2 unmapped\n");
+            _exit();
+        }
+    }
     return 0;
 } // end _v2p_translate()