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

From: Guo Ren
Date: Thu Nov 22 2018 - 00:44:48 EST


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_guo@xxxxxxxxx>
---
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