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 <linux/highmem.h>
22 #include <asm/mem-layout.h>
23 #include <asm/spr-regs.h>
24 #include <asm/mb-regs.h>
25 
26 #define NR_TLB_LINES		64	/* number of lines in the TLB */
27 
28 #ifndef __ASSEMBLY__
29 
30 #include <linux/interrupt.h>
31 #include <asm/kmap_types.h>
32 #include <asm/pgtable.h>
33 
34 #ifdef CONFIG_DEBUG_HIGHMEM
35 #define HIGHMEM_DEBUG 1
36 #else
37 #define HIGHMEM_DEBUG 0
38 #endif
39 
40 /* declarations for highmem.c */
41 extern unsigned long highstart_pfn, highend_pfn;
42 
43 #define kmap_prot PAGE_KERNEL
44 #define kmap_pte ______kmap_pte_in_TLB
45 extern pte_t *pkmap_page_table;
46 
47 #define flush_cache_kmaps()  do { } while (0)
48 
49 /*
50  * Right now we initialize only a single pte table. It can be extended
51  * easily, subsequent pte tables have to be allocated in one physical
52  * chunk of RAM.
53  */
54 #define LAST_PKMAP	PTRS_PER_PTE
55 #define LAST_PKMAP_MASK	(LAST_PKMAP - 1)
56 #define PKMAP_NR(virt)	((virt - PKMAP_BASE) >> PAGE_SHIFT)
57 #define PKMAP_ADDR(nr)	(PKMAP_BASE + ((nr) << PAGE_SHIFT))
58 
59 extern void *kmap_high(struct page *page);
60 extern void kunmap_high(struct page *page);
61 
62 extern void *kmap(struct page *page);
63 extern void kunmap(struct page *page);
64 
65 extern struct page *kmap_atomic_to_page(void *ptr);
66 
67 #endif /* !__ASSEMBLY__ */
68 
69 /*
70  * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
71  * gives a more generic (and caching) interface. But kmap_atomic can
72  * be used in IRQ contexts, so in some (very limited) cases we need
73  * it.
74  */
75 #define KMAP_ATOMIC_CACHE_DAMR		8
76 
77 #ifndef __ASSEMBLY__
78 
79 #define __kmap_atomic_primary(type, paddr, ampr)						\
80 ({												\
81 	unsigned long damlr, dampr;								\
82 												\
83 	dampr = paddr | xAMPRx_L | xAMPRx_M | xAMPRx_S | xAMPRx_SS_16Kb | xAMPRx_V;		\
84 												\
85 	if (type != __KM_CACHE)									\
86 		asm volatile("movgs %0,dampr"#ampr :: "r"(dampr) : "memory");			\
87 	else											\
88 		asm volatile("movgs %0,iampr"#ampr"\n"						\
89 			     "movgs %0,dampr"#ampr"\n"						\
90 			     :: "r"(dampr) : "memory"						\
91 			     );									\
92 												\
93 	asm("movsg damlr"#ampr",%0" : "=r"(damlr));						\
94 												\
95 	/*printk("DAMR"#ampr": PRIM sl=%d L=%08lx P=%08lx\n", type, damlr, dampr);*/		\
96 												\
97 	(void *) damlr;										\
98 })
99 
100 #define __kmap_atomic_secondary(slot, paddr)							  \
101 ({												  \
102 	unsigned long damlr = KMAP_ATOMIC_SECONDARY_FRAME + (slot) * PAGE_SIZE;			  \
103 	unsigned long dampr = paddr | xAMPRx_L | xAMPRx_M | xAMPRx_S | xAMPRx_SS_16Kb | xAMPRx_V; \
104 												  \
105 	asm volatile("movgs %0,tplr \n"								  \
106 		     "movgs %1,tppr \n"								  \
107 		     "tlbpr %0,gr0,#2,#1"							  \
108 		     : : "r"(damlr), "r"(dampr) : "memory");					  \
109 												  \
110 	/*printk("TLB: SECN sl=%d L=%08lx P=%08lx\n", slot, damlr, dampr);*/			  \
111 												  \
112 	(void *) damlr;										  \
113 })
114 
kmap_atomic_primary(struct page * page,enum km_type type)115 static inline void *kmap_atomic_primary(struct page *page, enum km_type type)
116 {
117 	unsigned long paddr;
118 
119 	pagefault_disable();
120 	paddr = page_to_phys(page);
121 
122 	switch (type) {
123         case 0:		return __kmap_atomic_primary(0, paddr, 2);
124         case 1:		return __kmap_atomic_primary(1, paddr, 3);
125         case 2:		return __kmap_atomic_primary(2, paddr, 4);
126         case 3:		return __kmap_atomic_primary(3, paddr, 5);
127 
128 	default:
129 		BUG();
130 		return NULL;
131 	}
132 }
133 
134 #define __kunmap_atomic_primary(type, ampr)				\
135 do {									\
136 	asm volatile("movgs gr0,dampr"#ampr"\n" ::: "memory");		\
137 	if (type == __KM_CACHE)						\
138 		asm volatile("movgs gr0,iampr"#ampr"\n" ::: "memory");	\
139 } while(0)
140 
141 #define __kunmap_atomic_secondary(slot, vaddr)				\
142 do {									\
143 	asm volatile("tlbpr %0,gr0,#4,#1" : : "r"(vaddr) : "memory");	\
144 } while(0)
145 
kunmap_atomic_primary(void * kvaddr,enum km_type type)146 static inline void kunmap_atomic_primary(void *kvaddr, enum km_type type)
147 {
148 	switch (type) {
149         case 0:		__kunmap_atomic_primary(0, 2);	break;
150         case 1:		__kunmap_atomic_primary(1, 3);	break;
151         case 2:		__kunmap_atomic_primary(2, 4);	break;
152         case 3:		__kunmap_atomic_primary(3, 5);	break;
153 
154 	default:
155 		BUG();
156 	}
157 	pagefault_enable();
158 }
159 
160 void *__kmap_atomic(struct page *page);
161 void __kunmap_atomic(void *kvaddr);
162 
163 #endif /* !__ASSEMBLY__ */
164 
165 #endif /* __KERNEL__ */
166 
167 #endif /* _ASM_HIGHMEM_H */
168