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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh64/mm/tlb.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/sh64/mm/tlb.c')
-rw-r--r--arch/sh64/mm/tlb.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/sh64/mm/tlb.c b/arch/sh64/mm/tlb.c
new file mode 100644
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+++ b/arch/sh64/mm/tlb.c
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1/*
2 * arch/sh64/mm/tlb.c
3 *
4 * Copyright (C) 2003 Paul Mundt <lethal@linux-sh.org>
5 * Copyright (C) 2003 Richard Curnow <richard.curnow@superh.com>
6 *
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License. See the file "COPYING" in the main directory of this archive
9 * for more details.
10 *
11 */
12#include <linux/mm.h>
13#include <linux/init.h>
14#include <asm/page.h>
15#include <asm/tlb.h>
16#include <asm/mmu_context.h>
17
18/**
19 * sh64_tlb_init
20 *
21 * Perform initial setup for the DTLB and ITLB.
22 */
23int __init sh64_tlb_init(void)
24{
25 /* Assign some sane DTLB defaults */
26 cpu_data->dtlb.entries = 64;
27 cpu_data->dtlb.step = 0x10;
28
29 cpu_data->dtlb.first = DTLB_FIXED | cpu_data->dtlb.step;
30 cpu_data->dtlb.next = cpu_data->dtlb.first;
31
32 cpu_data->dtlb.last = DTLB_FIXED |
33 ((cpu_data->dtlb.entries - 1) *
34 cpu_data->dtlb.step);
35
36 /* And again for the ITLB */
37 cpu_data->itlb.entries = 64;
38 cpu_data->itlb.step = 0x10;
39
40 cpu_data->itlb.first = ITLB_FIXED | cpu_data->itlb.step;
41 cpu_data->itlb.next = cpu_data->itlb.first;
42 cpu_data->itlb.last = ITLB_FIXED |
43 ((cpu_data->itlb.entries - 1) *
44 cpu_data->itlb.step);
45
46 return 0;
47}
48
49/**
50 * sh64_next_free_dtlb_entry
51 *
52 * Find the next available DTLB entry
53 */
54unsigned long long sh64_next_free_dtlb_entry(void)
55{
56 return cpu_data->dtlb.next;
57}
58
59/**
60 * sh64_get_wired_dtlb_entry
61 *
62 * Allocate a wired (locked-in) entry in the DTLB
63 */
64unsigned long long sh64_get_wired_dtlb_entry(void)
65{
66 unsigned long long entry = sh64_next_free_dtlb_entry();
67
68 cpu_data->dtlb.first += cpu_data->dtlb.step;
69 cpu_data->dtlb.next += cpu_data->dtlb.step;
70
71 return entry;
72}
73
74/**
75 * sh64_put_wired_dtlb_entry
76 *
77 * @entry: Address of TLB slot.
78 *
79 * Free a wired (locked-in) entry in the DTLB.
80 *
81 * Works like a stack, last one to allocate must be first one to free.
82 */
83int sh64_put_wired_dtlb_entry(unsigned long long entry)
84{
85 __flush_tlb_slot(entry);
86
87 /*
88 * We don't do any particularly useful tracking of wired entries,
89 * so this approach works like a stack .. last one to be allocated
90 * has to be the first one to be freed.
91 *
92 * We could potentially load wired entries into a list and work on
93 * rebalancing the list periodically (which also entails moving the
94 * contents of a TLB entry) .. though I have a feeling that this is
95 * more trouble than it's worth.
96 */
97
98 /*
99 * Entry must be valid .. we don't want any ITLB addresses!
100 */
101 if (entry <= DTLB_FIXED)
102 return -EINVAL;
103
104 /*
105 * Next, check if we're within range to be freed. (ie, must be the
106 * entry beneath the first 'free' entry!
107 */
108 if (entry < (cpu_data->dtlb.first - cpu_data->dtlb.step))
109 return -EINVAL;
110
111 /* If we are, then bring this entry back into the list */
112 cpu_data->dtlb.first -= cpu_data->dtlb.step;
113 cpu_data->dtlb.next = entry;
114
115 return 0;
116}
117
118/**
119 * sh64_setup_tlb_slot
120 *
121 * @config_addr: Address of TLB slot.
122 * @eaddr: Virtual address.
123 * @asid: Address Space Identifier.
124 * @paddr: Physical address.
125 *
126 * Load up a virtual<->physical translation for @eaddr<->@paddr in the
127 * pre-allocated TLB slot @config_addr (see sh64_get_wired_dtlb_entry).
128 */
129inline void sh64_setup_tlb_slot(unsigned long long config_addr,
130 unsigned long eaddr,
131 unsigned long asid,
132 unsigned long paddr)
133{
134 unsigned long long pteh, ptel;
135
136 /* Sign extension */
137#if (NEFF == 32)
138 pteh = (unsigned long long)(signed long long)(signed long) eaddr;
139#else
140#error "Can't sign extend more than 32 bits yet"
141#endif
142 pteh &= PAGE_MASK;
143 pteh |= (asid << PTEH_ASID_SHIFT) | PTEH_VALID;
144#if (NEFF == 32)
145 ptel = (unsigned long long)(signed long long)(signed long) paddr;
146#else
147#error "Can't sign extend more than 32 bits yet"
148#endif
149 ptel &= PAGE_MASK;
150 ptel |= (_PAGE_CACHABLE | _PAGE_READ | _PAGE_WRITE);
151
152 asm volatile("putcfg %0, 1, %1\n\t"
153 "putcfg %0, 0, %2\n"
154 : : "r" (config_addr), "r" (ptel), "r" (pteh));
155}
156
157/**
158 * sh64_teardown_tlb_slot
159 *
160 * @config_addr: Address of TLB slot.
161 *
162 * Teardown any existing mapping in the TLB slot @config_addr.
163 */
164inline void sh64_teardown_tlb_slot(unsigned long long config_addr)
165 __attribute__ ((alias("__flush_tlb_slot")));
166