FRV: Switch unaligned access to the packed-struct implementation
[linux-2.6] / include / asm-frv / highmem.h
1 /* highmem.h: virtual kernel memory mappings for high memory
2  *
3  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  * - Derived from include/asm-i386/highmem.h
6  *
7  * See Documentation/frv/mmu-layout.txt for more information.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version
12  * 2 of the License, or (at your option) any later version.
13  */
14
15 #ifndef _ASM_HIGHMEM_H
16 #define _ASM_HIGHMEM_H
17
18 #ifdef __KERNEL__
19
20 #include <linux/init.h>
21 #include <asm/mem-layout.h>
22 #include <asm/spr-regs.h>
23 #include <asm/mb-regs.h>
24
25 #define NR_TLB_LINES            64      /* number of lines in the TLB */
26
27 #ifndef __ASSEMBLY__
28
29 #include <linux/interrupt.h>
30 #include <asm/kmap_types.h>
31 #include <asm/pgtable.h>
32
33 #ifdef CONFIG_DEBUG_HIGHMEM
34 #define HIGHMEM_DEBUG 1
35 #else
36 #define HIGHMEM_DEBUG 0
37 #endif
38
39 /* declarations for highmem.c */
40 extern unsigned long highstart_pfn, highend_pfn;
41
42 #define kmap_prot PAGE_KERNEL
43 #define kmap_pte ______kmap_pte_in_TLB
44 extern pte_t *pkmap_page_table;
45
46 #define flush_cache_kmaps()  do { } while (0)
47
48 /*
49  * Right now we initialize only a single pte table. It can be extended
50  * easily, subsequent pte tables have to be allocated in one physical
51  * chunk of RAM.
52  */
53 #define LAST_PKMAP      PTRS_PER_PTE
54 #define LAST_PKMAP_MASK (LAST_PKMAP - 1)
55 #define PKMAP_NR(virt)  ((virt - PKMAP_BASE) >> PAGE_SHIFT)
56 #define PKMAP_ADDR(nr)  (PKMAP_BASE + ((nr) << PAGE_SHIFT))
57
58 extern void *kmap_high(struct page *page);
59 extern void kunmap_high(struct page *page);
60
61 extern void *kmap(struct page *page);
62 extern void kunmap(struct page *page);
63
64 extern struct page *kmap_atomic_to_page(void *ptr);
65
66 #endif /* !__ASSEMBLY__ */
67
68 /*
69  * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
70  * gives a more generic (and caching) interface. But kmap_atomic can
71  * be used in IRQ contexts, so in some (very limited) cases we need
72  * it.
73  */
74 #define KMAP_ATOMIC_CACHE_DAMR          8
75
76 #ifndef __ASSEMBLY__
77
78 #define __kmap_atomic_primary(type, paddr, ampr)                                                \
79 ({                                                                                              \
80         unsigned long damlr, dampr;                                                             \
81                                                                                                 \
82         dampr = paddr | xAMPRx_L | xAMPRx_M | xAMPRx_S | xAMPRx_SS_16Kb | xAMPRx_V;             \
83                                                                                                 \
84         if (type != __KM_CACHE)                                                                 \
85                 asm volatile("movgs %0,dampr"#ampr :: "r"(dampr) : "memory");                   \
86         else                                                                                    \
87                 asm volatile("movgs %0,iampr"#ampr"\n"                                          \
88                              "movgs %0,dampr"#ampr"\n"                                          \
89                              :: "r"(dampr) : "memory"                                           \
90                              );                                                                 \
91                                                                                                 \
92         asm("movsg damlr"#ampr",%0" : "=r"(damlr));                                             \
93                                                                                                 \
94         /*printk("DAMR"#ampr": PRIM sl=%d L=%08lx P=%08lx\n", type, damlr, dampr);*/            \
95                                                                                                 \
96         (void *) damlr;                                                                         \
97 })
98
99 #define __kmap_atomic_secondary(slot, paddr)                                                      \
100 ({                                                                                                \
101         unsigned long damlr = KMAP_ATOMIC_SECONDARY_FRAME + (slot) * PAGE_SIZE;                   \
102         unsigned long dampr = paddr | xAMPRx_L | xAMPRx_M | xAMPRx_S | xAMPRx_SS_16Kb | xAMPRx_V; \
103                                                                                                   \
104         asm volatile("movgs %0,tplr \n"                                                           \
105                      "movgs %1,tppr \n"                                                           \
106                      "tlbpr %0,gr0,#2,#1"                                                         \
107                      : : "r"(damlr), "r"(dampr) : "memory");                                      \
108                                                                                                   \
109         /*printk("TLB: SECN sl=%d L=%08lx P=%08lx\n", slot, damlr, dampr);*/                      \
110                                                                                                   \
111         (void *) damlr;                                                                           \
112 })
113
114 static inline void *kmap_atomic(struct page *page, enum km_type type)
115 {
116         unsigned long paddr;
117
118         pagefault_disable();
119         paddr = page_to_phys(page);
120
121         switch (type) {
122         case 0:         return __kmap_atomic_primary(0, paddr, 2);
123         case 1:         return __kmap_atomic_primary(1, paddr, 3);
124         case 2:         return __kmap_atomic_primary(2, paddr, 4);
125         case 3:         return __kmap_atomic_primary(3, paddr, 5);
126         case 4:         return __kmap_atomic_primary(4, paddr, 6);
127         case 5:         return __kmap_atomic_primary(5, paddr, 7);
128         case 6:         return __kmap_atomic_primary(6, paddr, 8);
129         case 7:         return __kmap_atomic_primary(7, paddr, 9);
130         case 8:         return __kmap_atomic_primary(8, paddr, 10);
131
132         case 9 ... 9 + NR_TLB_LINES - 1:
133                 return __kmap_atomic_secondary(type - 9, paddr);
134
135         default:
136                 BUG();
137                 return NULL;
138         }
139 }
140
141 #define __kunmap_atomic_primary(type, ampr)                             \
142 do {                                                                    \
143         asm volatile("movgs gr0,dampr"#ampr"\n" ::: "memory");          \
144         if (type == __KM_CACHE)                                         \
145                 asm volatile("movgs gr0,iampr"#ampr"\n" ::: "memory");  \
146 } while(0)
147
148 #define __kunmap_atomic_secondary(slot, vaddr)                          \
149 do {                                                                    \
150         asm volatile("tlbpr %0,gr0,#4,#1" : : "r"(vaddr) : "memory");   \
151 } while(0)
152
153 static inline void kunmap_atomic(void *kvaddr, enum km_type type)
154 {
155         switch (type) {
156         case 0:         __kunmap_atomic_primary(0, 2);  break;
157         case 1:         __kunmap_atomic_primary(1, 3);  break;
158         case 2:         __kunmap_atomic_primary(2, 4);  break;
159         case 3:         __kunmap_atomic_primary(3, 5);  break;
160         case 4:         __kunmap_atomic_primary(4, 6);  break;
161         case 5:         __kunmap_atomic_primary(5, 7);  break;
162         case 6:         __kunmap_atomic_primary(6, 8);  break;
163         case 7:         __kunmap_atomic_primary(7, 9);  break;
164         case 8:         __kunmap_atomic_primary(8, 10); break;
165
166         case 9 ... 9 + NR_TLB_LINES - 1:
167                 __kunmap_atomic_secondary(type - 9, kvaddr);
168                 break;
169
170         default:
171                 BUG();
172         }
173         pagefault_enable();
174 }
175
176 #endif /* !__ASSEMBLY__ */
177
178 #endif /* __KERNEL__ */
179
180 #endif /* _ASM_HIGHMEM_H */