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 */
 41extern unsigned long highstart_pfn, highend_pfn;
 42
 43#define kmap_prot PAGE_KERNEL
 44#define kmap_pte ______kmap_pte_in_TLB
 45extern 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
 59extern void *kmap_high(struct page *page);
 60extern void kunmap_high(struct page *page);
 61
 62extern void *kmap(struct page *page);
 63extern void kunmap(struct page *page);
 64
 65extern 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
115static 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)				\
135do {									\
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)				\
142do {									\
143	asm volatile("tlbpr %0,gr0,#4,#1" : : "r"(vaddr) : "memory");	\
144} while(0)
145
146static 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
160void *kmap_atomic(struct page *page);
161void __kunmap_atomic(void *kvaddr);
162
163#endif /* !__ASSEMBLY__ */
164
165#endif /* __KERNEL__ */
166
167#endif /* _ASM_HIGHMEM_H */