[PATCH 1/2] csky: bugfix tlb_get_pgd error.

[Guo Ren]

It's wrong to mask/unmask highest bit in addr to translate the vaddr
to paddr. We should use PAGE_OFFSET and PHYS_OFFSET.

Wrong implement:
  return ((get_pgd()|(1<<31)) - PHYS_OFFSET) & ~1;

When PHYS_OFFSET=0xc0000000 and get_pgd() return 0xe0000000, it'll
return 0x60000000. It's wrong and should be 0xa0000000.

Now correct it to:
  return ((get_pgd() - PHYS_OFFSET) & ~1) + PAGE_OFFSET;

Signed-off-by: Guo Ren <ren_...@c-sky.com>
---
 arch/csky/include/asm/mmu_context.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/csky/include/asm/mmu_context.h 
b/arch/csky/include/asm/mmu_context.h
index c410aa4..b2905c0 100644
--- a/arch/csky/include/asm/mmu_context.h
+++ b/arch/csky/include/asm/mmu_context.h
@@ -16,7 +16,7 @@
 
 static inline void tlbmiss_handler_setup_pgd(unsigned long pgd, bool kernel)
 {
-       pgd &= ~(1<<31);
+       pgd -= PAGE_OFFSET;
        pgd += PHYS_OFFSET;
        pgd |= 1;
        setup_pgd(pgd, kernel);
@@ -29,7 +29,7 @@ static inline void tlbmiss_handler_setup_pgd(unsigned long 
pgd, bool kernel)
 
 static inline unsigned long tlb_get_pgd(void)
 {
-       return ((get_pgd()|(1<<31)) - PHYS_OFFSET) & ~1;
+       return ((get_pgd() - PHYS_OFFSET) & ~1) + PAGE_OFFSET;
 }
 
 #define cpu_context(cpu, mm)   ((mm)->context.asid[cpu])
-- 
2.7.4