From f50b153b1966230e78034d5ab1641ca4bb5db56d Mon Sep 17 00:00:00 2001 From: Kumar Gala Date: Sat, 16 Apr 2005 15:24:22 -0700 Subject: [PATCH] ppc32: Support 36-bit physical addressing on e500 To add support for 36-bit physical addressing on e500 the following changes have been made. The changes are generalized to support any physical address size larger than 32-bits: * Allow FSL Book-E parts to use a 64-bit PTE, it is 44-bits of pfn, 20-bits of flags. * Introduced new CPU feature (CPU_FTR_BIG_PHYS) to allow runtime handling of updating hardware register (SPRN_MAS7) which holds the upper 32-bits of physical address that will be written into the TLB. This is useful since not all e500 cores support 36-bit physical addressing. * Currently have a pass through implementation of fixup_bigphys_addr * Moved _PAGE_DIRTY in the 64-bit PTE case to free room for three additional storage attributes that may exist in future FSL Book-E cores and updated fault handler to copy these bits into the hardware TLBs. Signed-off-by: Kumar Gala Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ppc/kernel/head_fsl_booke.S | 113 +++++++++++++++++++++++++-------------- 1 file changed, 73 insertions(+), 40 deletions(-) (limited to 'arch/ppc/kernel/head_fsl_booke.S') diff --git a/arch/ppc/kernel/head_fsl_booke.S b/arch/ppc/kernel/head_fsl_booke.S index dea19c216fc3..d64bf61d2b1f 100644 --- a/arch/ppc/kernel/head_fsl_booke.S +++ b/arch/ppc/kernel/head_fsl_booke.S @@ -347,6 +347,38 @@ skpinv: addi r6,r6,1 /* Increment */ mtspr SPRN_SRR1,r3 rfi /* change context and jump to start_kernel */ +/* Macros to hide the PTE size differences + * + * FIND_PTE -- walks the page tables given EA & pgdir pointer + * r10 -- EA of fault + * r11 -- PGDIR pointer + * r12 -- free + * label 2: is the bailout case + * + * if we find the pte (fall through): + * r11 is low pte word + * r12 is pointer to the pte + */ +#ifdef CONFIG_PTE_64BIT +#define PTE_FLAGS_OFFSET 4 +#define FIND_PTE \ + rlwinm r12, r10, 13, 19, 29; /* Compute pgdir/pmd offset */ \ + lwzx r11, r12, r11; /* Get pgd/pmd entry */ \ + rlwinm. r12, r11, 0, 0, 20; /* Extract pt base address */ \ + beq 2f; /* Bail if no table */ \ + rlwimi r12, r10, 23, 20, 28; /* Compute pte address */ \ + lwz r11, 4(r12); /* Get pte entry */ +#else +#define PTE_FLAGS_OFFSET 0 +#define FIND_PTE \ + rlwimi r11, r10, 12, 20, 29; /* Create L1 (pgdir/pmd) address */ \ + lwz r11, 0(r11); /* Get L1 entry */ \ + rlwinm. r12, r11, 0, 0, 19; /* Extract L2 (pte) base address */ \ + beq 2f; /* Bail if no table */ \ + rlwimi r12, r10, 22, 20, 29; /* Compute PTE address */ \ + lwz r11, 0(r12); /* Get Linux PTE */ +#endif + /* * Interrupt vector entry code * @@ -405,13 +437,7 @@ interrupt_base: mfspr r11,SPRN_SPRG3 lwz r11,PGDIR(r11) 4: - rlwimi r11, r10, 12, 20, 29 /* Create L1 (pgdir/pmd) address */ - lwz r11, 0(r11) /* Get L1 entry */ - rlwinm. r12, r11, 0, 0, 19 /* Extract L2 (pte) base address */ - beq 2f /* Bail if no table */ - - rlwimi r12, r10, 22, 20, 29 /* Compute PTE address */ - lwz r11, 0(r12) /* Get Linux PTE */ + FIND_PTE /* Are _PAGE_USER & _PAGE_RW set & _PAGE_HWWRITE not? */ andi. r13, r11, _PAGE_RW|_PAGE_USER|_PAGE_HWWRITE @@ -420,14 +446,12 @@ interrupt_base: /* Update 'changed'. */ ori r11, r11, _PAGE_DIRTY|_PAGE_ACCESSED|_PAGE_HWWRITE - stw r11, 0(r12) /* Update Linux page table */ + stw r11, PTE_FLAGS_OFFSET(r12) /* Update Linux page table */ /* MAS2 not updated as the entry does exist in the tlb, this fault taken to detect state transition (eg: COW -> DIRTY) */ - lis r12, MAS3_RPN@h - ori r12, r12, _PAGE_HWEXEC | MAS3_RPN@l - and r11, r11, r12 + andi. r11, r11, _PAGE_HWEXEC rlwimi r11, r11, 31, 27, 27 /* SX <- _PAGE_HWEXEC */ ori r11, r11, (MAS3_UW|MAS3_SW|MAS3_UR|MAS3_SR)@l /* set static perms */ @@ -439,7 +463,10 @@ interrupt_base: /* find the TLB index that caused the fault. It has to be here. */ tlbsx 0, r10 - mtspr SPRN_MAS3,r11 + /* only update the perm bits, assume the RPN is fine */ + mfspr r12, SPRN_MAS3 + rlwimi r12, r11, 0, 20, 31 + mtspr SPRN_MAS3,r12 tlbwe /* Done...restore registers and get out of here. */ @@ -530,18 +557,15 @@ interrupt_base: lwz r11,PGDIR(r11) 4: - rlwimi r11, r10, 12, 20, 29 /* Create L1 (pgdir/pmd) address */ - lwz r11, 0(r11) /* Get L1 entry */ - rlwinm. r12, r11, 0, 0, 19 /* Extract L2 (pte) base address */ - beq 2f /* Bail if no table */ - - rlwimi r12, r10, 22, 20, 29 /* Compute PTE address */ - lwz r11, 0(r12) /* Get Linux PTE */ - andi. r13, r11, _PAGE_PRESENT - beq 2f + FIND_PTE + andi. r13, r11, _PAGE_PRESENT /* Is the page present? */ + beq 2f /* Bail if not present */ +#ifdef CONFIG_PTE_64BIT + lwz r13, 0(r12) +#endif ori r11, r11, _PAGE_ACCESSED - stw r11, 0(r12) + stw r11, PTE_FLAGS_OFFSET(r12) /* Jump to common tlb load */ b finish_tlb_load @@ -594,18 +618,15 @@ interrupt_base: lwz r11,PGDIR(r11) 4: - rlwimi r11, r10, 12, 20, 29 /* Create L1 (pgdir/pmd) address */ - lwz r11, 0(r11) /* Get L1 entry */ - rlwinm. r12, r11, 0, 0, 19 /* Extract L2 (pte) base address */ - beq 2f /* Bail if no table */ - - rlwimi r12, r10, 22, 20, 29 /* Compute PTE address */ - lwz r11, 0(r12) /* Get Linux PTE */ - andi. r13, r11, _PAGE_PRESENT - beq 2f + FIND_PTE + andi. r13, r11, _PAGE_PRESENT /* Is the page present? */ + beq 2f /* Bail if not present */ +#ifdef CONFIG_PTE_64BIT + lwz r13, 0(r12) +#endif ori r11, r11, _PAGE_ACCESSED - stw r11, 0(r12) + stw r11, PTE_FLAGS_OFFSET(r12) /* Jump to common TLB load point */ b finish_tlb_load @@ -690,27 +711,39 @@ finish_tlb_load: */ mfspr r12, SPRN_MAS2 +#ifdef CONFIG_PTE_64BIT + rlwimi r12, r11, 26, 24, 31 /* extract ...WIMGE from pte */ +#else rlwimi r12, r11, 26, 27, 31 /* extract WIMGE from pte */ +#endif mtspr SPRN_MAS2, r12 bge 5, 1f - /* addr > TASK_SIZE */ - li r10, (MAS3_UX | MAS3_UW | MAS3_UR) - andi. r13, r11, (_PAGE_USER | _PAGE_HWWRITE | _PAGE_HWEXEC) - andi. r12, r11, _PAGE_USER /* Test for _PAGE_USER */ - iseleq r12, 0, r10 - and r10, r12, r13 - srwi r12, r10, 1 + /* is user addr */ + andi. r12, r11, (_PAGE_USER | _PAGE_HWWRITE | _PAGE_HWEXEC) + andi. r10, r11, _PAGE_USER /* Test for _PAGE_USER */ + srwi r10, r12, 1 or r12, r12, r10 /* Copy user perms into supervisor */ + iseleq r12, 0, r12 b 2f - /* addr <= TASK_SIZE */ + /* is kernel addr */ 1: rlwinm r12, r11, 31, 29, 29 /* Extract _PAGE_HWWRITE into SW */ ori r12, r12, (MAS3_SX | MAS3_SR) +#ifdef CONFIG_PTE_64BIT +2: rlwimi r12, r13, 24, 0, 7 /* grab RPN[32:39] */ + rlwimi r12, r11, 24, 8, 19 /* grab RPN[40:51] */ + mtspr SPRN_MAS3, r12 +BEGIN_FTR_SECTION + srwi r10, r13, 8 /* grab RPN[8:31] */ + mtspr SPRN_MAS7, r10 +END_FTR_SECTION_IFSET(CPU_FTR_BIG_PHYS) +#else 2: rlwimi r11, r12, 0, 20, 31 /* Extract RPN from PTE and merge with perms */ mtspr SPRN_MAS3, r11 +#endif tlbwe /* Done...restore registers and get out of here. */ -- cgit v1.2.3