parisc: allow to build with 16k default kernel page size

Introduce new convert_for_tlb_insert20 macro and use it to replace assembler
statements with hardcoded constants.
This change allows the parisc64 kernel to boot with 16kb default kernel page size,
aka CONFIG_PARISC_PAGE_SIZE_16KB=y.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>

diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S
index 0f7ff93..4e9dd15 100644 (file)
--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -505,6 +505,18 @@
        STREG           \pte,0(\ptep)
        .endm
 
+       /* bitshift difference between a PFN (based on kernel's PAGE_SIZE)
+        * to a CPU TLB 4k PFN (4k => 12 bits to shift) */
+       #define PAGE_ADD_SHIFT  (PAGE_SHIFT-12)
+
+       /* Drop prot bits and convert to page addr for iitlbt and idtlbt */
+       .macro          convert_for_tlb_insert20 pte
+       extrd,u         \pte,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\
+                               64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte
+       depdi           _PAGE_SIZE_ENCODING_DEFAULT,63,\
+                               (63-58)+PAGE_ADD_SHIFT,\pte
+       .endm
+
        /* Convert the pte and prot to tlb insertion values.  How
         * this happens is quite subtle, read below */
        .macro          make_insert_tlb spc,pte,prot
@@ -544,8 +556,7 @@
        depi            1,12,1,\prot
 
        /* Drop prot bits and convert to page addr for iitlbt and idtlbt */
-       extrd,u         \pte,(63-ASM_PFN_PTE_SHIFT)+(63-58),64-PAGE_SHIFT,\pte
-       depdi           _PAGE_SIZE_ENCODING_DEFAULT,63,63-58,\pte
+       convert_for_tlb_insert20 \pte
        .endm
 
        /* Identical macro to make_insert_tlb above, except it
@@ -1244,10 +1255,9 @@ nadtlb_check_flush_20w:
        depdi,z         7,7,3,prot
        depdi           1,10,1,prot
 
-       /* Get rid of prot bits and convert to page addr for idtlbt */
+       /* Drop prot bits from pte and convert to page addr for idtlbt */
+       convert_for_tlb_insert20 pte
 
-       depdi           0,63,12,pte
-       extrd,u         pte,56,52,pte
        idtlbt          pte,prot
 
        rfir
@@ -1403,10 +1413,9 @@ nadtlb_check_flush_20:
        depdi,z         7,7,3,prot
        depdi           1,10,1,prot
 
-       /* Get rid of prot bits and convert to page addr for idtlbt */
+       /* Drop prot bits from pte and convert to page addr for idtlbt */
+       convert_for_tlb_insert20 pte
 
-       depdi           0,63,12,pte
-       extrd,u         pte,56,32,pte
        idtlbt          pte,prot
 
        rfir