From 64b3d0e8122b422e879b23d42f9e0e8efbbf9744 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Thu, 18 Dec 2008 19:13:51 +0000 Subject: powerpc/mm: Rework usage of _PAGE_COHERENT/NO_CACHE/GUARDED Currently, we never set _PAGE_COHERENT in the PTEs, we just OR it in in the hash code based on some CPU feature bit. We also manipulate _PAGE_NO_CACHE and _PAGE_GUARDED by hand in all sorts of places. This changes the logic so that instead, the PTE now contains _PAGE_COHERENT for all normal RAM pages thay have I = 0 on platforms that need it. The hash code clears it if the feature bit is not set. It also adds some clean accessors to setup various valid combinations of access flags and change various bits of code to use them instead. This should help having the PTE actually containing the bit combinations that we really want. I also removed _PAGE_GUARDED from _PAGE_BASE on 44x and instead set it explicitely from the TLB miss. I will ultimately remove it completely as it appears that it might not be needed after all but in the meantime, having it in the TLB miss makes things a lot easier. Signed-off-by: Benjamin Herrenschmidt Acked-by: Kumar Gala Signed-off-by: Paul Mackerras --- arch/powerpc/mm/hash_low_32.S | 4 ++-- arch/powerpc/mm/mem.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/powerpc/mm') diff --git a/arch/powerpc/mm/hash_low_32.S b/arch/powerpc/mm/hash_low_32.S index c8eac22a8f00..28845604a10c 100644 --- a/arch/powerpc/mm/hash_low_32.S +++ b/arch/powerpc/mm/hash_low_32.S @@ -323,8 +323,8 @@ _GLOBAL(create_hpte) ori r8,r8,0xe14 /* clear out reserved bits and M */ andc r8,r5,r8 /* PP = user? (rw&dirty? 2: 3): 0 */ BEGIN_FTR_SECTION - ori r8,r8,_PAGE_COHERENT /* set M (coherence required) */ -END_FTR_SECTION_IFSET(CPU_FTR_NEED_COHERENT) + rlwinm r8,r8,0,~_PAGE_COHERENT /* clear M (coherence not required) */ +END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT) #ifdef CONFIG_PTE_64BIT /* Put the XPN bits into the PTE */ rlwimi r8,r10,8,20,22 diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 8fee696fb795..53b06ebb3f2f 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -102,8 +102,8 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); if (!page_is_ram(pfn)) - vma_prot = __pgprot(pgprot_val(vma_prot) - | _PAGE_GUARDED | _PAGE_NO_CACHE); + vma_prot = pgprot_noncached(vma_prot); + return vma_prot; } EXPORT_SYMBOL(phys_mem_access_prot); -- cgit v1.2.3