From 4ee7084eb11e00eb02dc8435fd18273a61ffa9bf Mon Sep 17 00:00:00 2001 From: Becky Bruce Date: Wed, 24 Sep 2008 11:01:24 -0500 Subject: POWERPC: Allow 32-bit hashed pgtable code to support 36-bit physical This rearranges a bit of code, and adds support for 36-bit physical addressing for configs that use a hashed page table. The 36b physical support is not enabled by default on any config - it must be explicitly enabled via the config system. This patch *only* expands the page table code to accomodate large physical addresses on 32-bit systems and enables the PHYS_64BIT config option for 86xx. It does *not* allow you to boot a board with more than about 3.5GB of RAM - for that, SWIOTLB support is also required (and coming soon). Signed-off-by: Becky Bruce Signed-off-by: Kumar Gala --- arch/powerpc/mm/hash_low_32.S | 86 +++++++++++++++++++++++++++++++++++-------- 1 file changed, 70 insertions(+), 16 deletions(-) (limited to 'arch/powerpc/mm/hash_low_32.S') diff --git a/arch/powerpc/mm/hash_low_32.S b/arch/powerpc/mm/hash_low_32.S index c41d658176a..7bffb70b9fe 100644 --- a/arch/powerpc/mm/hash_low_32.S +++ b/arch/powerpc/mm/hash_low_32.S @@ -75,7 +75,7 @@ _GLOBAL(hash_page_sync) * Returns to the caller if the access is illegal or there is no * mapping for the address. Otherwise it places an appropriate PTE * in the hash table and returns from the exception. - * Uses r0, r3 - r8, ctr, lr. + * Uses r0, r3 - r8, r10, ctr, lr. */ .text _GLOBAL(hash_page) @@ -106,9 +106,15 @@ _GLOBAL(hash_page) addi r5,r5,swapper_pg_dir@l /* kernel page table */ rlwimi r3,r9,32-12,29,29 /* MSR_PR -> _PAGE_USER */ 112: add r5,r5,r7 /* convert to phys addr */ +#ifndef CONFIG_PTE_64BIT rlwimi r5,r4,12,20,29 /* insert top 10 bits of address */ lwz r8,0(r5) /* get pmd entry */ rlwinm. r8,r8,0,0,19 /* extract address of pte page */ +#else + rlwinm r8,r4,13,19,29 /* Compute pgdir/pmd offset */ + lwzx r8,r8,r5 /* Get L1 entry */ + rlwinm. r8,r8,0,0,20 /* extract pt base address */ +#endif #ifdef CONFIG_SMP beq- hash_page_out /* return if no mapping */ #else @@ -118,7 +124,11 @@ _GLOBAL(hash_page) to the address following the rfi. */ beqlr- #endif +#ifndef CONFIG_PTE_64BIT rlwimi r8,r4,22,20,29 /* insert next 10 bits of address */ +#else + rlwimi r8,r4,23,20,28 /* compute pte address */ +#endif rlwinm r0,r3,32-3,24,24 /* _PAGE_RW access -> _PAGE_DIRTY */ ori r0,r0,_PAGE_ACCESSED|_PAGE_HASHPTE @@ -127,9 +137,15 @@ _GLOBAL(hash_page) * because almost always, there won't be a permission violation * and there won't already be an HPTE, and thus we will have * to update the PTE to set _PAGE_HASHPTE. -- paulus. + * + * If PTE_64BIT is set, the low word is the flags word; use that + * word for locking since it contains all the interesting bits. */ +#if (PTE_FLAGS_OFFSET != 0) + addi r8,r8,PTE_FLAGS_OFFSET +#endif retry: - lwarx r6,0,r8 /* get linux-style pte */ + lwarx r6,0,r8 /* get linux-style pte, flag word */ andc. r5,r3,r6 /* check access & ~permission */ #ifdef CONFIG_SMP bne- hash_page_out /* return if access not permitted */ @@ -137,6 +153,15 @@ retry: bnelr- #endif or r5,r0,r6 /* set accessed/dirty bits */ +#ifdef CONFIG_PTE_64BIT +#ifdef CONFIG_SMP + subf r10,r6,r8 /* create false data dependency */ + subi r10,r10,PTE_FLAGS_OFFSET + lwzx r10,r6,r10 /* Get upper PTE word */ +#else + lwz r10,-PTE_FLAGS_OFFSET(r8) +#endif /* CONFIG_SMP */ +#endif /* CONFIG_PTE_64BIT */ stwcx. r5,0,r8 /* attempt to update PTE */ bne- retry /* retry if someone got there first */ @@ -203,9 +228,9 @@ _GLOBAL(add_hash_page) * we can't take a hash table miss (assuming the code is * covered by a BAT). -- paulus */ - mfmsr r10 + mfmsr r9 SYNC - rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ + rlwinm r0,r9,0,17,15 /* clear bit 16 (MSR_EE) */ rlwinm r0,r0,0,28,26 /* clear MSR_DR */ mtmsr r0 SYNC_601 @@ -214,14 +239,14 @@ _GLOBAL(add_hash_page) tophys(r7,0) #ifdef CONFIG_SMP - addis r9,r7,mmu_hash_lock@ha - addi r9,r9,mmu_hash_lock@l -10: lwarx r0,0,r9 /* take the mmu_hash_lock */ + addis r6,r7,mmu_hash_lock@ha + addi r6,r6,mmu_hash_lock@l +10: lwarx r0,0,r6 /* take the mmu_hash_lock */ cmpi 0,r0,0 bne- 11f - stwcx. r8,0,r9 + stwcx. r8,0,r6 beq+ 12f -11: lwz r0,0(r9) +11: lwz r0,0(r6) cmpi 0,r0,0 beq 10b b 11b @@ -234,10 +259,24 @@ _GLOBAL(add_hash_page) * HPTE, so we just unlock and return. */ mr r8,r5 +#ifndef CONFIG_PTE_64BIT rlwimi r8,r4,22,20,29 +#else + rlwimi r8,r4,23,20,28 + addi r8,r8,PTE_FLAGS_OFFSET +#endif 1: lwarx r6,0,r8 andi. r0,r6,_PAGE_HASHPTE bne 9f /* if HASHPTE already set, done */ +#ifdef CONFIG_PTE_64BIT +#ifdef CONFIG_SMP + subf r10,r6,r8 /* create false data dependency */ + subi r10,r10,PTE_FLAGS_OFFSET + lwzx r10,r6,r10 /* Get upper PTE word */ +#else + lwz r10,-PTE_FLAGS_OFFSET(r8) +#endif /* CONFIG_SMP */ +#endif /* CONFIG_PTE_64BIT */ ori r5,r6,_PAGE_HASHPTE stwcx. r5,0,r8 bne- 1b @@ -246,13 +285,15 @@ _GLOBAL(add_hash_page) 9: #ifdef CONFIG_SMP + addis r6,r7,mmu_hash_lock@ha + addi r6,r6,mmu_hash_lock@l eieio li r0,0 - stw r0,0(r9) /* clear mmu_hash_lock */ + stw r0,0(r6) /* clear mmu_hash_lock */ #endif /* reenable interrupts and DR */ - mtmsr r10 + mtmsr r9 SYNC_601 isync @@ -267,7 +308,8 @@ _GLOBAL(add_hash_page) * r5 contains the linux PTE, r6 contains the old value of the * linux PTE (before setting _PAGE_HASHPTE) and r7 contains the * offset to be added to addresses (0 if the MMU is on, - * -KERNELBASE if it is off). + * -KERNELBASE if it is off). r10 contains the upper half of + * the PTE if CONFIG_PTE_64BIT. * On SMP, the caller should have the mmu_hash_lock held. * We assume that the caller has (or will) set the _PAGE_HASHPTE * bit in the linux PTE in memory. The value passed in r6 should @@ -313,6 +355,11 @@ _GLOBAL(create_hpte) BEGIN_FTR_SECTION ori r8,r8,_PAGE_COHERENT /* set M (coherence required) */ END_FTR_SECTION_IFSET(CPU_FTR_NEED_COHERENT) +#ifdef CONFIG_PTE_64BIT + /* Put the XPN bits into the PTE */ + rlwimi r8,r10,8,20,22 + rlwimi r8,r10,2,29,29 +#endif /* Construct the high word of the PPC-style PTE (r5) */ rlwinm r5,r3,7,1,24 /* put VSID in 0x7fffff80 bits */ @@ -499,14 +546,18 @@ _GLOBAL(flush_hash_pages) isync /* First find a PTE in the range that has _PAGE_HASHPTE set */ +#ifndef CONFIG_PTE_64BIT rlwimi r5,r4,22,20,29 -1: lwz r0,0(r5) +#else + rlwimi r5,r4,23,20,28 +#endif +1: lwz r0,PTE_FLAGS_OFFSET(r5) cmpwi cr1,r6,1 andi. r0,r0,_PAGE_HASHPTE bne 2f ble cr1,19f addi r4,r4,0x1000 - addi r5,r5,4 + addi r5,r5,PTE_SIZE addi r6,r6,-1 b 1b @@ -545,7 +596,10 @@ _GLOBAL(flush_hash_pages) * already clear, we're done (for this pte). If not, * clear it (atomically) and proceed. -- paulus. */ -33: lwarx r8,0,r5 /* fetch the pte */ +#if (PTE_FLAGS_OFFSET != 0) + addi r5,r5,PTE_FLAGS_OFFSET +#endif +33: lwarx r8,0,r5 /* fetch the pte flags word */ andi. r0,r8,_PAGE_HASHPTE beq 8f /* done if HASHPTE is already clear */ rlwinm r8,r8,0,31,29 /* clear HASHPTE bit */ @@ -590,7 +644,7 @@ _GLOBAL(flush_hash_patch_B) 8: ble cr1,9f /* if all ptes checked */ 81: addi r6,r6,-1 - addi r5,r5,4 /* advance to next pte */ + addi r5,r5,PTE_SIZE addi r4,r4,0x1000 lwz r0,0(r5) /* check next pte */ cmpwi cr1,r6,1 -- cgit v1.2.3