diff options
Diffstat (limited to 'arch/arc/mm/tlb.c')
| -rw-r--r-- | arch/arc/mm/tlb.c | 782 |
1 files changed, 421 insertions, 361 deletions
diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c index 7957dc4e4d4a..ed6915ba76ec 100644 --- a/arch/arc/mm/tlb.c +++ b/arch/arc/mm/tlb.c @@ -1,207 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0-only /* - * TLB Management (flush/create/diagnostics) for ARC700 + * TLB Management (flush/create/diagnostics) for MMUv3 and MMUv4 * * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * vineetg: Aug 2011 - * -Reintroduce duplicate PD fixup - some customer chips still have the issue - * - * vineetg: May 2011 - * -No need to flush_cache_page( ) for each call to update_mmu_cache() - * some of the LMBench tests improved amazingly - * = page-fault thrice as fast (75 usec to 28 usec) - * = mmap twice as fast (9.6 msec to 4.6 msec), - * = fork (5.3 msec to 3.7 msec) - * - * vineetg: April 2011 : - * -MMU v3: PD{0,1} bits layout changed: They don't overlap anymore, - * helps avoid a shift when preparing PD0 from PTE - * - * vineetg: April 2011 : Preparing for MMU V3 - * -MMU v2/v3 BCRs decoded differently - * -Remove TLB_SIZE hardcoding as it's variable now: 256 or 512 - * -tlb_entry_erase( ) can be void - * -local_flush_tlb_range( ): - * = need not "ceil" @end - * = walks MMU only if range spans < 32 entries, as opposed to 256 - * - * Vineetg: Sept 10th 2008 - * -Changes related to MMU v2 (Rel 4.8) - * - * Vineetg: Aug 29th 2008 - * -In TLB Flush operations (Metal Fix MMU) there is a explict command to - * flush Micro-TLBS. If TLB Index Reg is invalid prior to TLBIVUTLB cmd, - * it fails. Thus need to load it with ANY valid value before invoking - * TLBIVUTLB cmd - * - * Vineetg: Aug 21th 2008: - * -Reduced the duration of IRQ lockouts in TLB Flush routines - * -Multiple copies of TLB erase code seperated into a "single" function - * -In TLB Flush routines, interrupt disabling moved UP to retrieve ASID - * in interrupt-safe region. - * - * Vineetg: April 23rd Bug #93131 - * Problem: tlb_flush_kernel_range() doesnt do anything if the range to - * flush is more than the size of TLB itself. - * - * Rahul Trivedi : Codito Technologies 2004 */ #include <linux/module.h> +#include <linux/bug.h> +#include <linux/mm_types.h> + #include <asm/arcregs.h> #include <asm/setup.h> #include <asm/mmu_context.h> #include <asm/mmu.h> -/* Need for ARC MMU v2 - * - * ARC700 MMU-v1 had a Joint-TLB for Code and Data and is 2 way set-assoc. - * For a memcpy operation with 3 players (src/dst/code) such that all 3 pages - * map into same set, there would be contention for the 2 ways causing severe - * Thrashing. - * - * Although J-TLB is 2 way set assoc, ARC700 caches J-TLB into uTLBS which has - * much higher associativity. u-D-TLB is 8 ways, u-I-TLB is 4 ways. - * Given this, the thrasing problem should never happen because once the 3 - * J-TLB entries are created (even though 3rd will knock out one of the prev - * two), the u-D-TLB and u-I-TLB will have what is required to accomplish memcpy - * - * Yet we still see the Thrashing because a J-TLB Write cause flush of u-TLBs. - * This is a simple design for keeping them in sync. So what do we do? - * The solution which James came up was pretty neat. It utilised the assoc - * of uTLBs by not invalidating always but only when absolutely necessary. - * - * - Existing TLB commands work as before - * - New command (TLBWriteNI) for TLB write without clearing uTLBs - * - New command (TLBIVUTLB) to invalidate uTLBs. - * - * The uTLBs need only be invalidated when pages are being removed from the - * OS page table. If a 'victim' TLB entry is being overwritten in the main TLB - * as a result of a miss, the removed entry is still allowed to exist in the - * uTLBs as it is still valid and present in the OS page table. This allows the - * full associativity of the uTLBs to hide the limited associativity of the main - * TLB. - * - * During a miss handler, the new "TLBWriteNI" command is used to load - * entries without clearing the uTLBs. - * - * When the OS page table is updated, TLB entries that may be associated with a - * removed page are removed (flushed) from the TLB using TLBWrite. In this - * circumstance, the uTLBs must also be cleared. This is done by using the - * existing TLBWrite command. An explicit IVUTLB is also required for those - * corner cases when TLBWrite was not executed at all because the corresp - * J-TLB entry got evicted/replaced. - */ - - /* A copy of the ASID from the PID reg is kept in asid_cache */ -int asid_cache = FIRST_ASID; +DEFINE_PER_CPU(unsigned int, asid_cache) = MM_CTXT_FIRST_CYCLE; -/* ASID to mm struct mapping. We have one extra entry corresponding to - * NO_ASID to save us a compare when clearing the mm entry for old asid - * see get_new_mmu_context (asm-arc/mmu_context.h) - */ -struct mm_struct *asid_mm_map[NUM_ASID + 1]; +static struct cpuinfo_arc_mmu { + unsigned int ver, pg_sz_k, s_pg_sz_m, pae, sets, ways; +} mmuinfo; /* * Utility Routine to erase a J-TLB entry - * The procedure is to look it up in the MMU. If found, ERASE it by - * issuing a TlbWrite CMD with PD0 = PD1 = 0 + * Caller needs to setup Index Reg (manually or via getIndex) */ - -static void __tlb_entry_erase(void) +static inline void __tlb_entry_erase(void) { write_aux_reg(ARC_REG_TLBPD1, 0); + + if (is_pae40_enabled()) + write_aux_reg(ARC_REG_TLBPD1HI, 0); + write_aux_reg(ARC_REG_TLBPD0, 0); write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite); } -static void tlb_entry_erase(unsigned int vaddr_n_asid) +static void utlb_invalidate(void) +{ + write_aux_reg(ARC_REG_TLBCOMMAND, TLBIVUTLB); +} + +#ifdef CONFIG_ARC_MMU_V3 + +static inline unsigned int tlb_entry_lkup(unsigned long vaddr_n_asid) { unsigned int idx; - /* Locate the TLB entry for this vaddr + ASID */ write_aux_reg(ARC_REG_TLBPD0, vaddr_n_asid); + write_aux_reg(ARC_REG_TLBCOMMAND, TLBProbe); idx = read_aux_reg(ARC_REG_TLBINDEX); + return idx; +} + +static void tlb_entry_erase(unsigned int vaddr_n_asid) +{ + unsigned int idx; + + /* Locate the TLB entry for this vaddr + ASID */ + idx = tlb_entry_lkup(vaddr_n_asid); + /* No error means entry found, zero it out */ if (likely(!(idx & TLB_LKUP_ERR))) { __tlb_entry_erase(); - } else { /* Some sort of Error */ - + } else { /* Duplicate entry error */ - if (idx & 0x1) { - /* TODO we need to handle this case too */ - pr_emerg("unhandled Duplicate flush for %x\n", - vaddr_n_asid); - } - /* else entry not found so nothing to do */ + WARN(idx == TLB_DUP_ERR, "Probe returned Dup PD for %x\n", + vaddr_n_asid); } } -/**************************************************************************** - * ARC700 MMU caches recently used J-TLB entries (RAM) as uTLBs (FLOPs) - * - * New IVUTLB cmd in MMU v2 explictly invalidates the uTLB - * - * utlb_invalidate ( ) - * -For v2 MMU calls Flush uTLB Cmd - * -For v1 MMU does nothing (except for Metal Fix v1 MMU) - * This is because in v1 TLBWrite itself invalidate uTLBs - ***************************************************************************/ - -static void utlb_invalidate(void) +static void tlb_entry_insert(unsigned int pd0, phys_addr_t pd1) { -#if (CONFIG_ARC_MMU_VER >= 2) - -#if (CONFIG_ARC_MMU_VER < 3) - /* MMU v2 introduced the uTLB Flush command. - * There was however an obscure hardware bug, where uTLB flush would - * fail when a prior probe for J-TLB (both totally unrelated) would - * return lkup err - because the entry didnt exist in MMU. - * The Workround was to set Index reg with some valid value, prior to - * flush. This was fixed in MMU v3 hence not needed any more - */ unsigned int idx; - /* make sure INDEX Reg is valid */ - idx = read_aux_reg(ARC_REG_TLBINDEX); + /* + * First verify if entry for this vaddr+ASID already exists + * This also sets up PD0 (vaddr, ASID..) for final commit + */ + idx = tlb_entry_lkup(pd0); - /* If not write some dummy val */ - if (unlikely(idx & TLB_LKUP_ERR)) - write_aux_reg(ARC_REG_TLBINDEX, 0xa); -#endif + /* + * If Not already present get a free slot from MMU. + * Otherwise, Probe would have located the entry and set INDEX Reg + * with existing location. This will cause Write CMD to over-write + * existing entry with new PD0 and PD1 + */ + if (likely(idx & TLB_LKUP_ERR)) + write_aux_reg(ARC_REG_TLBCOMMAND, TLBGetIndex); - write_aux_reg(ARC_REG_TLBCOMMAND, TLBIVUTLB); -#endif + /* setup the other half of TLB entry (pfn, rwx..) */ + write_aux_reg(ARC_REG_TLBPD1, pd1); + /* + * Commit the Entry to MMU + * It doesn't sound safe to use the TLBWriteNI cmd here + * which doesn't flush uTLBs. I'd rather be safe than sorry. + */ + write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite); +} + +#else /* MMUv4 */ + +static void tlb_entry_erase(unsigned int vaddr_n_asid) +{ + write_aux_reg(ARC_REG_TLBPD0, vaddr_n_asid | _PAGE_PRESENT); + write_aux_reg(ARC_REG_TLBCOMMAND, TLBDeleteEntry); } +static void tlb_entry_insert(unsigned int pd0, phys_addr_t pd1) +{ + write_aux_reg(ARC_REG_TLBPD0, pd0); + + if (!is_pae40_enabled()) { + write_aux_reg(ARC_REG_TLBPD1, pd1); + } else { + write_aux_reg(ARC_REG_TLBPD1, pd1 & 0xFFFFFFFF); + write_aux_reg(ARC_REG_TLBPD1HI, (u64)pd1 >> 32); + } + + write_aux_reg(ARC_REG_TLBCOMMAND, TLBInsertEntry); +} + +#endif + /* * Un-conditionally (without lookup) erase the entire MMU contents */ noinline void local_flush_tlb_all(void) { + struct cpuinfo_arc_mmu *mmu = &mmuinfo; unsigned long flags; unsigned int entry; - struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu; + int num_tlb = mmu->sets * mmu->ways; local_irq_save(flags); /* Load PD0 and PD1 with template for a Blank Entry */ write_aux_reg(ARC_REG_TLBPD1, 0); + + if (is_pae40_enabled()) + write_aux_reg(ARC_REG_TLBPD1HI, 0); + write_aux_reg(ARC_REG_TLBPD0, 0); - for (entry = 0; entry < mmu->num_tlb; entry++) { + for (entry = 0; entry < num_tlb; entry++) { /* write this entry to the TLB */ write_aux_reg(ARC_REG_TLBINDEX, entry); - write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite); + write_aux_reg(ARC_REG_TLBCOMMAND, TLBWriteNI); + } + + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { + const int stlb_idx = 0x800; + + /* Blank sTLB entry */ + write_aux_reg(ARC_REG_TLBPD0, _PAGE_HW_SZ); + + for (entry = stlb_idx; entry < stlb_idx + 16; entry++) { + write_aux_reg(ARC_REG_TLBINDEX, entry); + write_aux_reg(ARC_REG_TLBCOMMAND, TLBWriteNI); + } } utlb_invalidate(); @@ -210,7 +172,7 @@ noinline void local_flush_tlb_all(void) } /* - * Flush the entrie MM for userland. The fastest way is to move to Next ASID + * Flush the entire MM for userland. The fastest way is to move to Next ASID */ noinline void local_flush_tlb_mm(struct mm_struct *mm) { @@ -224,13 +186,14 @@ noinline void local_flush_tlb_mm(struct mm_struct *mm) return; /* - * Workaround for Android weirdism: - * A binder VMA could end up in a task such that vma->mm != tsk->mm - * old code would cause h/w - s/w ASID to get out of sync + * - Move to a new ASID, but only if the mm is still wired in + * (Android Binder ended up calling this for vma->mm != tsk->mm, + * causing h/w - s/w ASID to get out of sync) + * - Also get_new_mmu_context() new implementation allocates a new + * ASID only if it is not allocated already - so unallocate first */ - if (current->mm != mm) - destroy_context(mm); - else + destroy_context(mm); + if (current->mm == mm) get_new_mmu_context(mm); } @@ -240,16 +203,16 @@ noinline void local_flush_tlb_mm(struct mm_struct *mm) * Difference between this and Kernel Range Flush is * -Here the fastest way (if range is too large) is to move to next ASID * without doing any explicit Shootdown - * -In case of kernel Flush, entry has to be shot down explictly + * -In case of kernel Flush, entry has to be shot down explicitly */ void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { + const unsigned int cpu = smp_processor_id(); unsigned long flags; - unsigned int asid; /* If range @start to @end is more than 32 TLB entries deep, - * its better to move to a new ASID rather than searching for + * it's better to move to a new ASID rather than searching for * individual entries and then shooting them down * * The calc above is rough, doesn't account for unaligned parts, @@ -268,17 +231,14 @@ void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, start &= PAGE_MASK; local_irq_save(flags); - asid = vma->vm_mm->context.asid; - if (asid != NO_ASID) { + if (asid_mm(vma->vm_mm, cpu) != MM_CTXT_NO_ASID) { while (start < end) { - tlb_entry_erase(start | (asid & 0xff)); + tlb_entry_erase(start | hw_pid(vma->vm_mm, cpu)); start += PAGE_SIZE; } } - utlb_invalidate(); - local_irq_restore(flags); } @@ -307,8 +267,6 @@ void local_flush_tlb_kernel_range(unsigned long start, unsigned long end) start += PAGE_SIZE; } - utlb_invalidate(); - local_irq_restore(flags); } @@ -319,6 +277,7 @@ void local_flush_tlb_kernel_range(unsigned long start, unsigned long end) void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page) { + const unsigned int cpu = smp_processor_id(); unsigned long flags; /* Note that it is critical that interrupts are DISABLED between @@ -326,23 +285,118 @@ void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page) */ local_irq_save(flags); - if (vma->vm_mm->context.asid != NO_ASID) { - tlb_entry_erase((page & PAGE_MASK) | - (vma->vm_mm->context.asid & 0xff)); - utlb_invalidate(); + if (asid_mm(vma->vm_mm, cpu) != MM_CTXT_NO_ASID) { + tlb_entry_erase((page & PAGE_MASK) | hw_pid(vma->vm_mm, cpu)); } local_irq_restore(flags); } +#ifdef CONFIG_SMP + +struct tlb_args { + struct vm_area_struct *ta_vma; + unsigned long ta_start; + unsigned long ta_end; +}; + +static inline void ipi_flush_tlb_page(void *arg) +{ + struct tlb_args *ta = arg; + + local_flush_tlb_page(ta->ta_vma, ta->ta_start); +} + +static inline void ipi_flush_tlb_range(void *arg) +{ + struct tlb_args *ta = arg; + + local_flush_tlb_range(ta->ta_vma, ta->ta_start, ta->ta_end); +} + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static inline void ipi_flush_pmd_tlb_range(void *arg) +{ + struct tlb_args *ta = arg; + + local_flush_pmd_tlb_range(ta->ta_vma, ta->ta_start, ta->ta_end); +} +#endif + +static inline void ipi_flush_tlb_kernel_range(void *arg) +{ + struct tlb_args *ta = (struct tlb_args *)arg; + + local_flush_tlb_kernel_range(ta->ta_start, ta->ta_end); +} + +void flush_tlb_all(void) +{ + on_each_cpu((smp_call_func_t)local_flush_tlb_all, NULL, 1); +} + +void flush_tlb_mm(struct mm_struct *mm) +{ + on_each_cpu_mask(mm_cpumask(mm), (smp_call_func_t)local_flush_tlb_mm, + mm, 1); +} + +void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr) +{ + struct tlb_args ta = { + .ta_vma = vma, + .ta_start = uaddr + }; + + on_each_cpu_mask(mm_cpumask(vma->vm_mm), ipi_flush_tlb_page, &ta, 1); +} + +void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, + unsigned long end) +{ + struct tlb_args ta = { + .ta_vma = vma, + .ta_start = start, + .ta_end = end + }; + + on_each_cpu_mask(mm_cpumask(vma->vm_mm), ipi_flush_tlb_range, &ta, 1); +} + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +void flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start, + unsigned long end) +{ + struct tlb_args ta = { + .ta_vma = vma, + .ta_start = start, + .ta_end = end + }; + + on_each_cpu_mask(mm_cpumask(vma->vm_mm), ipi_flush_pmd_tlb_range, &ta, 1); +} +#endif + +void flush_tlb_kernel_range(unsigned long start, unsigned long end) +{ + struct tlb_args ta = { + .ta_start = start, + .ta_end = end + }; + + on_each_cpu(ipi_flush_tlb_kernel_range, &ta, 1); +} +#endif + /* * Routine to create a TLB entry */ -void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) +static void create_tlb(struct vm_area_struct *vma, unsigned long vaddr, pte_t *ptep) { unsigned long flags; - unsigned int idx, asid_or_sasid; - unsigned long pd0_flags; + unsigned int asid_or_sasid, rwx; + unsigned long pd0; + phys_addr_t pd1; /* * create_tlb() assumes that current->mm == vma->mm, since @@ -351,11 +405,10 @@ void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) * * Removing the assumption involves * -Using vma->mm->context{ASID,SASID}, as opposed to MMU reg. - * -Fix the TLB paranoid debug code to not trigger false negatives. * -More importantly it makes this handler inconsistent with fast-path * TLB Refill handler which always deals with "current" * - * Lets see the use cases when current->mm != vma->mm and we land here + * Let's see the use cases when current->mm != vma->mm and we land here * 1. execve->copy_strings()->__get_user_pages->handle_mm_fault * Here VM wants to pre-install a TLB entry for user stack while * current->mm still points to pre-execve mm (hence the condition). @@ -374,47 +427,35 @@ void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) local_irq_save(flags); - tlb_paranoid_check(vma->vm_mm->context.asid, address); - - address &= PAGE_MASK; + vaddr &= PAGE_MASK; /* update this PTE credentials */ pte_val(*ptep) |= (_PAGE_PRESENT | _PAGE_ACCESSED); - /* Create HW TLB entry Flags (in PD0) from PTE Flags */ -#if (CONFIG_ARC_MMU_VER <= 2) - pd0_flags = ((pte_val(*ptep) & PTE_BITS_IN_PD0) >> 1); -#else - pd0_flags = ((pte_val(*ptep) & PTE_BITS_IN_PD0)); -#endif + /* Create HW TLB(PD0,PD1) from PTE */ /* ASID for this task */ asid_or_sasid = read_aux_reg(ARC_REG_PID) & 0xff; - write_aux_reg(ARC_REG_TLBPD0, address | pd0_flags | asid_or_sasid); - - /* Load remaining info in PD1 (Page Frame Addr and Kx/Kw/Kr Flags) */ - write_aux_reg(ARC_REG_TLBPD1, (pte_val(*ptep) & PTE_BITS_IN_PD1)); - - /* First verify if entry for this vaddr+ASID already exists */ - write_aux_reg(ARC_REG_TLBCOMMAND, TLBProbe); - idx = read_aux_reg(ARC_REG_TLBINDEX); + pd0 = vaddr | asid_or_sasid | (pte_val(*ptep) & PTE_BITS_IN_PD0); /* - * If Not already present get a free slot from MMU. - * Otherwise, Probe would have located the entry and set INDEX Reg - * with existing location. This will cause Write CMD to over-write - * existing entry with new PD0 and PD1 + * ARC MMU provides fully orthogonal access bits for K/U mode, + * however Linux only saves 1 set to save PTE real-estate + * Here we convert 3 PTE bits into 6 MMU bits: + * -Kernel only entries have Kr Kw Kx 0 0 0 + * -User entries have mirrored K and U bits */ - if (likely(idx & TLB_LKUP_ERR)) - write_aux_reg(ARC_REG_TLBCOMMAND, TLBGetIndex); + rwx = pte_val(*ptep) & PTE_BITS_RWX; - /* - * Commit the Entry to MMU - * It doesnt sound safe to use the TLBWriteNI cmd here - * which doesn't flush uTLBs. I'd rather be safe than sorry. - */ - write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite); + if (pte_val(*ptep) & _PAGE_GLOBAL) + rwx <<= 3; /* r w x => Kr Kw Kx 0 0 0 */ + else + rwx |= (rwx << 3); /* r w x => Kr Kw Kx Ur Uw Ux */ + + pd1 = rwx | (pte_val(*ptep) & PTE_BITS_NON_RWX_IN_PD1); + + tlb_entry_insert(pd0, pd1); local_irq_restore(flags); } @@ -428,146 +469,199 @@ void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) * Note that flush (when done) involves both WBACK - so physical page is * in sync as well as INV - so any non-congruent aliases don't remain */ -void update_mmu_cache(struct vm_area_struct *vma, unsigned long vaddr_unaligned, - pte_t *ptep) +void update_mmu_cache_range(struct vm_fault *vmf, struct vm_area_struct *vma, + unsigned long vaddr_unaligned, pte_t *ptep, unsigned int nr) { unsigned long vaddr = vaddr_unaligned & PAGE_MASK; - unsigned long paddr = pte_val(*ptep) & PAGE_MASK; + phys_addr_t paddr = pte_val(*ptep) & PAGE_MASK_PHYS; struct page *page = pfn_to_page(pte_pfn(*ptep)); create_tlb(vma, vaddr, ptep); - if (page == ZERO_PAGE(0)) { + if (page == ZERO_PAGE(0)) return; - } /* - * Exec page : Independent of aliasing/page-color considerations, - * since icache doesn't snoop dcache on ARC, any dirty - * K-mapping of a code page needs to be wback+inv so that - * icache fetch by userspace sees code correctly. - * !EXEC page: If K-mapping is NOT congruent to U-mapping, flush it - * so userspace sees the right data. - * (Avoids the flush for Non-exec + congruent mapping case) + * For executable pages, since icache doesn't snoop dcache, any + * dirty K-mapping of a code page needs to be wback+inv so that + * icache fetch by userspace sees code correctly. */ - if ((vma->vm_flags & VM_EXEC) || - addr_not_cache_congruent(paddr, vaddr)) { - - int dirty = !test_and_set_bit(PG_dc_clean, &page->flags); + if (vma->vm_flags & VM_EXEC) { + struct folio *folio = page_folio(page); + int dirty = !test_and_set_bit(PG_dc_clean, &folio->flags.f); if (dirty) { - /* wback + inv dcache lines */ - __flush_dcache_page(paddr, paddr); - - /* invalidate any existing icache lines */ + unsigned long offset = offset_in_folio(folio, paddr); + nr = folio_nr_pages(folio); + paddr -= offset; + vaddr -= offset; + /* wback + inv dcache lines (K-mapping) */ + __flush_dcache_pages(paddr, paddr, nr); + + /* invalidate any existing icache lines (U-mapping) */ if (vma->vm_flags & VM_EXEC) - __inv_icache_page(paddr, vaddr); + __inv_icache_pages(paddr, vaddr, nr); } } } -/* Read the Cache Build Confuration Registers, Decode them and save into - * the cpuinfo structure for later use. - * No Validation is done here, simply read/convert the BCRs +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + +/* + * MMUv4 in HS38x cores supports Super Pages which are basis for Linux THP + * support. + * + * Normal and Super pages can co-exist (ofcourse not overlap) in TLB with a + * new bit "SZ" in TLB page descriptor to distinguish between them. + * Super Page size is configurable in hardware (4K to 16M), but fixed once + * RTL builds. + * + * The exact THP size a Linux configuration will support is a function of: + * - MMU page size (typical 8K, RTL fixed) + * - software page walker address split between PGD:PTE:PFN (typical + * 11:8:13, but can be changed with 1 line) + * So for above default, THP size supported is 8K * (2^8) = 2M + * + * Default Page Walker is 2 levels, PGD:PTE:PFN, which in THP regime + * reduces to 1 level (as PTE is folded into PGD and canonically referred + * to as PMD). + * Thus THP PMD accessors are implemented in terms of PTE (just like sparc) */ -void read_decode_mmu_bcr(void) + +void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr, + pmd_t *pmd) { - struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu; - unsigned int tmp; - struct bcr_mmu_1_2 { -#ifdef CONFIG_CPU_BIG_ENDIAN - unsigned int ver:8, ways:4, sets:4, u_itlb:8, u_dtlb:8; -#else - unsigned int u_dtlb:8, u_itlb:8, sets:4, ways:4, ver:8; -#endif - } *mmu2; - - struct bcr_mmu_3 { -#ifdef CONFIG_CPU_BIG_ENDIAN - unsigned int ver:8, ways:4, sets:4, osm:1, reserv:3, pg_sz:4, - u_itlb:4, u_dtlb:4; -#else - unsigned int u_dtlb:4, u_itlb:4, pg_sz:4, reserv:3, osm:1, sets:4, - ways:4, ver:8; -#endif - } *mmu3; - - tmp = read_aux_reg(ARC_REG_MMU_BCR); - mmu->ver = (tmp >> 24); - - if (mmu->ver <= 2) { - mmu2 = (struct bcr_mmu_1_2 *)&tmp; - mmu->pg_sz = PAGE_SIZE; - mmu->sets = 1 << mmu2->sets; - mmu->ways = 1 << mmu2->ways; - mmu->u_dtlb = mmu2->u_dtlb; - mmu->u_itlb = mmu2->u_itlb; - } else { - mmu3 = (struct bcr_mmu_3 *)&tmp; - mmu->pg_sz = 512 << mmu3->pg_sz; - mmu->sets = 1 << mmu3->sets; - mmu->ways = 1 << mmu3->ways; - mmu->u_dtlb = mmu3->u_dtlb; - mmu->u_itlb = mmu3->u_itlb; + pte_t pte = __pte(pmd_val(*pmd)); + update_mmu_cache_range(NULL, vma, addr, &pte, HPAGE_PMD_NR); +} + +void local_flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start, + unsigned long end) +{ + unsigned int cpu; + unsigned long flags; + + local_irq_save(flags); + + cpu = smp_processor_id(); + + if (likely(asid_mm(vma->vm_mm, cpu) != MM_CTXT_NO_ASID)) { + unsigned int asid = hw_pid(vma->vm_mm, cpu); + + /* No need to loop here: this will always be for 1 Huge Page */ + tlb_entry_erase(start | _PAGE_HW_SZ | asid); } - mmu->num_tlb = mmu->sets * mmu->ways; + local_irq_restore(flags); } -char *arc_mmu_mumbojumbo(int cpu_id, char *buf, int len) +#endif + +/* Read the Cache Build Configuration Registers, Decode them and save into + * the cpuinfo structure for later use. + * No Validation is done here, simply read/convert the BCRs + */ +int arc_mmu_mumbojumbo(int c, char *buf, int len) { + struct cpuinfo_arc_mmu *mmu = &mmuinfo; + unsigned int bcr, u_dtlb, u_itlb, sasid; + struct bcr_mmu_3 *mmu3; + struct bcr_mmu_4 *mmu4; + char super_pg[64] = ""; int n = 0; - struct cpuinfo_arc_mmu *p_mmu = &cpuinfo_arc700[cpu_id].mmu; - n += scnprintf(buf + n, len - n, "ARC700 MMU [v%x]\t: %dk PAGE, ", - p_mmu->ver, TO_KB(p_mmu->pg_sz)); + bcr = read_aux_reg(ARC_REG_MMU_BCR); + mmu->ver = (bcr >> 24); + + if (is_isa_arcompact() && mmu->ver == 3) { + mmu3 = (struct bcr_mmu_3 *)&bcr; + mmu->pg_sz_k = 1 << (mmu3->pg_sz - 1); + mmu->sets = 1 << mmu3->sets; + mmu->ways = 1 << mmu3->ways; + u_dtlb = mmu3->u_dtlb; + u_itlb = mmu3->u_itlb; + sasid = mmu3->sasid; + } else { + mmu4 = (struct bcr_mmu_4 *)&bcr; + mmu->pg_sz_k = 1 << (mmu4->sz0 - 1); + mmu->s_pg_sz_m = 1 << (mmu4->sz1 - 11); + mmu->sets = 64 << mmu4->n_entry; + mmu->ways = mmu4->n_ways * 2; + u_dtlb = mmu4->u_dtlb * 4; + u_itlb = mmu4->u_itlb * 4; + sasid = mmu4->sasid; + mmu->pae = mmu4->pae; + } + + if (mmu->s_pg_sz_m) + scnprintf(super_pg, 64, "/%dM%s", + mmu->s_pg_sz_m, + IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) ? " (THP enabled)":""); n += scnprintf(buf + n, len - n, - "J-TLB %d (%dx%d), uDTLB %d, uITLB %d, %s\n", - p_mmu->num_tlb, p_mmu->sets, p_mmu->ways, - p_mmu->u_dtlb, p_mmu->u_itlb, - IS_ENABLED(CONFIG_ARC_MMU_SASID) ? "SASID" : ""); + "MMU [v%x]\t: %dk%s, swalk %d lvl, JTLB %dx%d, uDTLB %d, uITLB %d%s%s%s\n", + mmu->ver, mmu->pg_sz_k, super_pg, CONFIG_PGTABLE_LEVELS, + mmu->sets, mmu->ways, + u_dtlb, u_itlb, + IS_AVAIL1(sasid, ", SASID"), + IS_AVAIL2(mmu->pae, ", PAE40 ", CONFIG_ARC_HAS_PAE40)); + + return n; +} - return buf; +int pae40_exist_but_not_enab(void) +{ + return mmuinfo.pae && !is_pae40_enabled(); } void arc_mmu_init(void) { - char str[256]; - struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu; - - printk(arc_mmu_mumbojumbo(0, str, sizeof(str))); - - /* For efficiency sake, kernel is compile time built for a MMU ver - * This must match the hardware it is running on. - * Linux built for MMU V2, if run on MMU V1 will break down because V1 - * hardware doesn't understand cmds such as WriteNI, or IVUTLB - * On the other hand, Linux built for V1 if run on MMU V2 will do - * un-needed workarounds to prevent memcpy thrashing. - * Similarly MMU V3 has new features which won't work on older MMU + struct cpuinfo_arc_mmu *mmu = &mmuinfo; + int compat = 0; + + /* + * Can't be done in processor.h due to header include dependencies */ - if (mmu->ver != CONFIG_ARC_MMU_VER) { - panic("MMU ver %d doesn't match kernel built for %d...\n", - mmu->ver, CONFIG_ARC_MMU_VER); - } + BUILD_BUG_ON(!IS_ALIGNED((CONFIG_ARC_KVADDR_SIZE << 20), PMD_SIZE)); - if (mmu->pg_sz != PAGE_SIZE) - panic("MMU pg size != PAGE_SIZE (%luk)\n", TO_KB(PAGE_SIZE)); + /* + * stack top size sanity check, + * Can't be done in processor.h due to header include dependencies + */ + BUILD_BUG_ON(!IS_ALIGNED(STACK_TOP, PMD_SIZE)); /* - * ASID mgmt data structures are compile time init - * asid_cache = FIRST_ASID and asid_mm_map[] all zeroes + * Ensure that MMU features assumed by kernel exist in hardware. + * - For older ARC700 cpus, only v3 supported + * - For HS cpus, v4 was baseline and v5 is backwards compatible + * (will run older software). */ + if (is_isa_arcompact() && mmu->ver == 3) + compat = 1; + else if (is_isa_arcv2() && mmu->ver >= 4) + compat = 1; - local_flush_tlb_all(); + if (!compat) + panic("MMU ver %d doesn't match kernel built for\n", mmu->ver); - /* Enable the MMU */ - write_aux_reg(ARC_REG_PID, MMU_ENABLE); + if (mmu->pg_sz_k != TO_KB(PAGE_SIZE)) + panic("MMU pg size != PAGE_SIZE (%luk)\n", TO_KB(PAGE_SIZE)); - /* In smp we use this reg for interrupt 1 scratch */ -#ifndef CONFIG_SMP - /* swapper_pg_dir is the pgd for the kernel, used by vmalloc */ - write_aux_reg(ARC_REG_SCRATCH_DATA0, swapper_pg_dir); -#endif + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && + mmu->s_pg_sz_m != TO_MB(HPAGE_PMD_SIZE)) + panic("MMU Super pg size != Linux HPAGE_PMD_SIZE (%luM)\n", + (unsigned long)TO_MB(HPAGE_PMD_SIZE)); + + if (IS_ENABLED(CONFIG_ARC_HAS_PAE40) && !mmu->pae) + panic("Hardware doesn't support PAE40\n"); + + /* Enable the MMU with ASID 0 */ + mmu_setup_asid(NULL, 0); + + /* cache the pgd pointer in MMU SCRATCH reg (ARCv2 only) */ + mmu_setup_pgd(NULL, swapper_pg_dir); + + if (pae40_exist_but_not_enab()) + write_aux_reg(ARC_REG_TLBPD1HI, 0); } /* @@ -595,32 +689,34 @@ void arc_mmu_init(void) * the duplicate one. * -Knob to be verbose abt it.(TODO: hook them up to debugfs) */ -volatile int dup_pd_verbose = 1;/* Be slient abt it or complain (default) */ +volatile int dup_pd_silent; /* Be silent abt it or complain (default) */ void do_tlb_overlap_fault(unsigned long cause, unsigned long address, struct pt_regs *regs) { - int set, way, n; - unsigned int pd0[4], pd1[4]; /* assume max 4 ways */ - unsigned long flags, is_valid; - struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu; + struct cpuinfo_arc_mmu *mmu = &mmuinfo; + unsigned long flags; + int set, n_ways = mmu->ways; - local_irq_save(flags); + n_ways = min(n_ways, 4); + BUG_ON(mmu->ways > 4); - /* re-enable the MMU */ - write_aux_reg(ARC_REG_PID, MMU_ENABLE | read_aux_reg(ARC_REG_PID)); + local_irq_save(flags); /* loop thru all sets of TLB */ for (set = 0; set < mmu->sets; set++) { + int is_valid, way; + unsigned int pd0[4]; + /* read out all the ways of current set */ - for (way = 0, is_valid = 0; way < mmu->ways; way++) { + for (way = 0, is_valid = 0; way < n_ways; way++) { write_aux_reg(ARC_REG_TLBINDEX, SET_WAY_TO_IDX(mmu, set, way)); write_aux_reg(ARC_REG_TLBCOMMAND, TLBRead); pd0[way] = read_aux_reg(ARC_REG_TLBPD0); - pd1[way] = read_aux_reg(ARC_REG_TLBPD1); is_valid |= pd0[way] & _PAGE_PRESENT; + pd0[way] &= PAGE_MASK; } /* If all the WAYS in SET are empty, skip to next SET */ @@ -628,68 +724,32 @@ void do_tlb_overlap_fault(unsigned long cause, unsigned long address, continue; /* Scan the set for duplicate ways: needs a nested loop */ - for (way = 0; way < mmu->ways; way++) { + for (way = 0; way < n_ways - 1; way++) { + + int n; + if (!pd0[way]) continue; - for (n = way + 1; n < mmu->ways; n++) { - if ((pd0[way] & PAGE_MASK) == - (pd0[n] & PAGE_MASK)) { - - if (dup_pd_verbose) { - pr_info("Duplicate PD's @" - "[%d:%d]/[%d:%d]\n", - set, way, set, n); - pr_info("TLBPD0[%u]: %08x\n", - way, pd0[way]); - } - - /* - * clear entry @way and not @n. This is - * critical to our optimised loop - */ - pd0[way] = pd1[way] = 0; - write_aux_reg(ARC_REG_TLBINDEX, + for (n = way + 1; n < n_ways; n++) { + if (pd0[way] != pd0[n]) + continue; + + if (!dup_pd_silent) + pr_info("Dup TLB PD0 %08x @ set %d ways %d,%d\n", + pd0[way], set, way, n); + + /* + * clear entry @way and not @n. + * This is critical to our optimised loop + */ + pd0[way] = 0; + write_aux_reg(ARC_REG_TLBINDEX, SET_WAY_TO_IDX(mmu, set, way)); - __tlb_entry_erase(); - } + __tlb_entry_erase(); } } } local_irq_restore(flags); } - -/*********************************************************************** - * Diagnostic Routines - * -Called from Low Level TLB Hanlders if things don;t look good - **********************************************************************/ - -#ifdef CONFIG_ARC_DBG_TLB_PARANOIA - -/* - * Low Level ASM TLB handler calls this if it finds that HW and SW ASIDS - * don't match - */ -void print_asid_mismatch(int is_fast_path) -{ - int pid_sw, pid_hw; - pid_sw = current->active_mm->context.asid; - pid_hw = read_aux_reg(ARC_REG_PID) & 0xff; - - pr_emerg("ASID Mismatch in %s Path Handler: sw-pid=0x%x hw-pid=0x%x\n", - is_fast_path ? "Fast" : "Slow", pid_sw, pid_hw); - - __asm__ __volatile__("flag 1"); -} - -void tlb_paranoid_check(unsigned int pid_sw, unsigned long addr) -{ - unsigned int pid_hw; - - pid_hw = read_aux_reg(ARC_REG_PID) & 0xff; - - if (addr < 0x70000000 && ((pid_hw != pid_sw) || (pid_sw == NO_ASID))) - print_asid_mismatch(0); -} -#endif |