ARC: MMUv4 preps/2 - Reshuffle PTE bits

With previous commit freeing up PTE bits, reassign them so as to:

- Match the bit to H/w counterpart where possible
  (e.g. MMUv2 GLOBAL/PRESENT, this avoids a shift in create_tlb())
- Avoid holes in _PAGE_xxx definitions

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/include/asm/pgtable.h

@@ -60,30 +60,24 @@
 #define _PAGE_EXECUTE       (1<<3)	/* Page has user execute perm (H) */
 #define _PAGE_WRITE         (1<<4)	/* Page has user write perm (H) */
 #define _PAGE_READ          (1<<5)	/* Page has user read perm (H) */
-#define _PAGE_GLOBAL        (1<<9)	/* Page is global (H) */
-#define _PAGE_MODIFIED      (1<<10)	/* Page modified (dirty) (S) */
-#define _PAGE_FILE          (1<<10)	/* page cache/ swap (S) */
-#define _PAGE_PRESENT       (1<<11)	/* TLB entry is valid (H) */
+#define _PAGE_MODIFIED      (1<<6)	/* Page modified (dirty) (S) */
+#define _PAGE_FILE          (1<<7)	/* page cache/ swap (S) */
+#define _PAGE_GLOBAL        (1<<8)	/* Page is global (H) */
+#define _PAGE_PRESENT       (1<<10)	/* TLB entry is valid (H) */
 
 #else	/* MMU v3 onwards */
 
-/* PD1 */
 #define _PAGE_CACHEABLE     (1<<0)	/* Page is cached (H) */
 #define _PAGE_EXECUTE       (1<<1)	/* Page has user execute perm (H) */
 #define _PAGE_WRITE         (1<<2)	/* Page has user write perm (H) */
 #define _PAGE_READ          (1<<3)	/* Page has user read perm (H) */
-#define _PAGE_ACCESSED      (1<<7)	/* Page is accessed (S) */
-
-/* PD0 */
+#define _PAGE_ACCESSED      (1<<4)	/* Page is accessed (S) */
+#define _PAGE_MODIFIED      (1<<5)	/* Page modified (dirty) (S) */
+#define _PAGE_FILE          (1<<6)	/* page cache/ swap (S) */
 #define _PAGE_GLOBAL        (1<<8)	/* Page is global (H) */
 #define _PAGE_PRESENT       (1<<9)	/* TLB entry is valid (H) */
-#define _PAGE_SHARED_CODE   (1<<10)	/* Shared Code page with cmn vaddr
+#define _PAGE_SHARED_CODE   (1<<11)	/* Shared Code page with cmn vaddr
 					   usable for shared TLB entries (H) */
-
-#define _PAGE_MODIFIED      (1<<11)	/* Page modified (dirty) (S) */
-#define _PAGE_FILE          (1<<12)	/* page cache/ swap (S) */
-
-#define _PAGE_SHARED_CODE_H (1<<31)	/* Hardware counterpart of above */
 #endif
 
 /* vmalloc permissions */

arch/arc/mm/tlb.c

@@ -342,7 +342,6 @@ void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
 {
 	unsigned long flags;
 	unsigned int idx, asid_or_sasid, rwx;
-	unsigned long pd0_flags;
 
 	/*
 	 * create_tlb() assumes that current->mm == vma->mm, since
@@ -381,17 +380,13 @@ void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
 	/* update this PTE credentials */
 	pte_val(*ptep) |= (_PAGE_PRESENT | _PAGE_ACCESSED);
 
-	/* Create HW TLB entry Flags (in PD0) from PTE Flags */
-#if (CONFIG_ARC_MMU_VER <= 2)
-	pd0_flags = ((pte_val(*ptep) & PTE_BITS_IN_PD0) >> 1);
-#else
-	pd0_flags = ((pte_val(*ptep) & PTE_BITS_IN_PD0));
-#endif
+	/* Create HW TLB(PD0,PD1) from PTE  */
 
 	/* ASID for this task */
 	asid_or_sasid = read_aux_reg(ARC_REG_PID) & 0xff;
 
-	write_aux_reg(ARC_REG_TLBPD0, address | pd0_flags | asid_or_sasid);
+	write_aux_reg(ARC_REG_TLBPD0, address | asid_or_sasid |
+				      (pte_val(*ptep) & PTE_BITS_IN_PD0));
 
 	/*
 	 * ARC MMU provides fully orthogonal access bits for K/U mode,

arch/arc/mm/tlbex.S

@@ -229,9 +229,6 @@ ex_saved_reg1:
 	sr  r3, [ARC_REG_TLBPD1]    	; these go in PD1
 
 	and r2, r0, PTE_BITS_IN_PD0 ; Extract other PTE flags: (V)alid, (G)lb
-#if (CONFIG_ARC_MMU_VER <= 2)   /* Neednot be done with v3 onwards */
-	lsr r2, r2                  ; shift PTE flags to match layout in PD0
-#endif
 
 	lr  r3,[ARC_REG_TLBPD0]     ; MMU prepares PD0 with vaddr and asid