1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Hexagon Virtual Machine TLB functions
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun /*
9*4882a593Smuzhiyun * The Hexagon Virtual Machine conceals the real workings of
10*4882a593Smuzhiyun * the TLB, but there are one or two functions that need to
11*4882a593Smuzhiyun * be instantiated for it, differently from a native build.
12*4882a593Smuzhiyun */
13*4882a593Smuzhiyun #include <linux/mm.h>
14*4882a593Smuzhiyun #include <linux/sched.h>
15*4882a593Smuzhiyun #include <asm/page.h>
16*4882a593Smuzhiyun #include <asm/hexagon_vm.h>
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun /*
19*4882a593Smuzhiyun * Initial VM implementation has only one map active at a time, with
20*4882a593Smuzhiyun * TLB purgings on changes. So either we're nuking the current map,
21*4882a593Smuzhiyun * or it's a no-op. This operation is messy on true SMPs where other
22*4882a593Smuzhiyun * processors must be induced to flush the copies in their local TLBs,
23*4882a593Smuzhiyun * but Hexagon thread-based virtual processors share the same MMU.
24*4882a593Smuzhiyun */
flush_tlb_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)25*4882a593Smuzhiyun void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
26*4882a593Smuzhiyun unsigned long end)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun struct mm_struct *mm = vma->vm_mm;
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun if (mm->context.ptbase == current->active_mm->context.ptbase)
31*4882a593Smuzhiyun __vmclrmap((void *)start, end - start);
32*4882a593Smuzhiyun }
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun /*
35*4882a593Smuzhiyun * Flush a page from the kernel virtual map - used by highmem
36*4882a593Smuzhiyun */
flush_tlb_one(unsigned long vaddr)37*4882a593Smuzhiyun void flush_tlb_one(unsigned long vaddr)
38*4882a593Smuzhiyun {
39*4882a593Smuzhiyun __vmclrmap((void *)vaddr, PAGE_SIZE);
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun /*
43*4882a593Smuzhiyun * Flush all TLBs across all CPUs, virtual or real.
44*4882a593Smuzhiyun * A single Hexagon core has 6 thread contexts but
45*4882a593Smuzhiyun * only one TLB.
46*4882a593Smuzhiyun */
tlb_flush_all(void)47*4882a593Smuzhiyun void tlb_flush_all(void)
48*4882a593Smuzhiyun {
49*4882a593Smuzhiyun /* should probably use that fixaddr end or whateve label */
50*4882a593Smuzhiyun __vmclrmap(0, 0xffff0000);
51*4882a593Smuzhiyun }
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun /*
54*4882a593Smuzhiyun * Flush TLB entries associated with a given mm_struct mapping.
55*4882a593Smuzhiyun */
flush_tlb_mm(struct mm_struct * mm)56*4882a593Smuzhiyun void flush_tlb_mm(struct mm_struct *mm)
57*4882a593Smuzhiyun {
58*4882a593Smuzhiyun /* Current Virtual Machine has only one map active at a time */
59*4882a593Smuzhiyun if (current->active_mm->context.ptbase == mm->context.ptbase)
60*4882a593Smuzhiyun tlb_flush_all();
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun
63*4882a593Smuzhiyun /*
64*4882a593Smuzhiyun * Flush TLB state associated with a page of a vma.
65*4882a593Smuzhiyun */
flush_tlb_page(struct vm_area_struct * vma,unsigned long vaddr)66*4882a593Smuzhiyun void flush_tlb_page(struct vm_area_struct *vma, unsigned long vaddr)
67*4882a593Smuzhiyun {
68*4882a593Smuzhiyun struct mm_struct *mm = vma->vm_mm;
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun if (mm->context.ptbase == current->active_mm->context.ptbase)
71*4882a593Smuzhiyun __vmclrmap((void *)vaddr, PAGE_SIZE);
72*4882a593Smuzhiyun }
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun /*
75*4882a593Smuzhiyun * Flush TLB entries associated with a kernel address range.
76*4882a593Smuzhiyun * Like flush range, but without the check on the vma->vm_mm.
77*4882a593Smuzhiyun */
flush_tlb_kernel_range(unsigned long start,unsigned long end)78*4882a593Smuzhiyun void flush_tlb_kernel_range(unsigned long start, unsigned long end)
79*4882a593Smuzhiyun {
80*4882a593Smuzhiyun __vmclrmap((void *)start, end - start);
81*4882a593Smuzhiyun }
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