1 /* MN10300 MMU context allocation and management
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11 #include <linux/sched.h>
12 #include <linux/mm.h>
13 #include <asm/mmu_context.h>
14 #include <asm/tlbflush.h>
15
16 #ifdef CONFIG_MN10300_TLB_USE_PIDR
17 /*
18 * list of the MMU contexts last allocated on each CPU
19 */
20 unsigned long mmu_context_cache[NR_CPUS] = {
21 [0 ... NR_CPUS - 1] =
22 MMU_CONTEXT_FIRST_VERSION * 2 - (1 - MMU_CONTEXT_TLBPID_LOCK_NR),
23 };
24 #endif /* CONFIG_MN10300_TLB_USE_PIDR */
25
26 /*
27 * preemptively set a TLB entry
28 */
update_mmu_cache(struct vm_area_struct * vma,unsigned long addr,pte_t * ptep)29 void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
30 {
31 unsigned long pteu, ptel, cnx, flags;
32 pte_t pte = *ptep;
33
34 addr &= PAGE_MASK;
35 ptel = pte_val(pte) & ~(xPTEL_UNUSED1 | xPTEL_UNUSED2);
36
37 /* make sure the context doesn't migrate and defend against
38 * interference from vmalloc'd regions */
39 local_irq_save(flags);
40
41 cnx = ~MMU_NO_CONTEXT;
42 #ifdef CONFIG_MN10300_TLB_USE_PIDR
43 cnx = mm_context(vma->vm_mm);
44 #endif
45
46 if (cnx != MMU_NO_CONTEXT) {
47 pteu = addr;
48 #ifdef CONFIG_MN10300_TLB_USE_PIDR
49 pteu |= cnx & MMU_CONTEXT_TLBPID_MASK;
50 #endif
51 if (!(pte_val(pte) & _PAGE_NX)) {
52 IPTEU = pteu;
53 if (IPTEL & xPTEL_V)
54 IPTEL = ptel;
55 }
56 DPTEU = pteu;
57 if (DPTEL & xPTEL_V)
58 DPTEL = ptel;
59 }
60
61 local_irq_restore(flags);
62 }
63