1 /*
2 * Hexagon Virtual Machine TLB functions
3 *
4 * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 and
8 * only version 2 as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18 * 02110-1301, USA.
19 */
20
21 /*
22 * The Hexagon Virtual Machine conceals the real workings of
23 * the TLB, but there are one or two functions that need to
24 * be instantiated for it, differently from a native build.
25 */
26 #include <linux/mm.h>
27 #include <asm/page.h>
28 #include <asm/hexagon_vm.h>
29
30 /*
31 * Initial VM implementation has only one map active at a time, with
32 * TLB purgings on changes. So either we're nuking the current map,
33 * or it's a no-op. This operation is messy on true SMPs where other
34 * processors must be induced to flush the copies in their local TLBs,
35 * but Hexagon thread-based virtual processors share the same MMU.
36 */
flush_tlb_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)37 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
38 unsigned long end)
39 {
40 struct mm_struct *mm = vma->vm_mm;
41
42 if (mm->context.ptbase == current->active_mm->context.ptbase)
43 __vmclrmap((void *)start, end - start);
44 }
45
46 /*
47 * Flush a page from the kernel virtual map - used by highmem
48 */
flush_tlb_one(unsigned long vaddr)49 void flush_tlb_one(unsigned long vaddr)
50 {
51 __vmclrmap((void *)vaddr, PAGE_SIZE);
52 }
53
54 /*
55 * Flush all TLBs across all CPUs, virtual or real.
56 * A single Hexagon core has 6 thread contexts but
57 * only one TLB.
58 */
tlb_flush_all(void)59 void tlb_flush_all(void)
60 {
61 /* should probably use that fixaddr end or whateve label */
62 __vmclrmap(0, 0xffff0000);
63 }
64
65 /*
66 * Flush TLB entries associated with a given mm_struct mapping.
67 */
flush_tlb_mm(struct mm_struct * mm)68 void flush_tlb_mm(struct mm_struct *mm)
69 {
70 /* Current Virtual Machine has only one map active at a time */
71 if (current->active_mm->context.ptbase == mm->context.ptbase)
72 tlb_flush_all();
73 }
74
75 /*
76 * Flush TLB state associated with a page of a vma.
77 */
flush_tlb_page(struct vm_area_struct * vma,unsigned long vaddr)78 void flush_tlb_page(struct vm_area_struct *vma, unsigned long vaddr)
79 {
80 struct mm_struct *mm = vma->vm_mm;
81
82 if (mm->context.ptbase == current->active_mm->context.ptbase)
83 __vmclrmap((void *)vaddr, PAGE_SIZE);
84 }
85
86 /*
87 * Flush TLB entries associated with a kernel address range.
88 * Like flush range, but without the check on the vma->vm_mm.
89 */
flush_tlb_kernel_range(unsigned long start,unsigned long end)90 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
91 {
92 __vmclrmap((void *)start, end - start);
93 }
94