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
 65#endif /* !__ASSEMBLY__ */
 66
 67/*
 68 * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
 69 * gives a more generic (and caching) interface. But kmap_atomic can
 70 * be used in IRQ contexts, so in some (very limited) cases we need
 71 * it.
 72 */
 73#define KMAP_ATOMIC_CACHE_DAMR		8
 74
 75#ifndef __ASSEMBLY__
 76
 77#define __kmap_atomic_primary(cached, paddr, ampr)						\
 78({												\
 79	unsigned long damlr, dampr;								\
 80												\
 81	dampr = paddr | xAMPRx_L | xAMPRx_M | xAMPRx_S | xAMPRx_SS_16Kb | xAMPRx_V;		\
 82												\
 83	if (!cached)										\
 84		asm volatile("movgs %0,dampr"#ampr :: "r"(dampr) : "memory");			\
 85	else											\
 86		/* cache flush page attachment point */						\
 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
114static inline void *kmap_atomic_primary(struct page *page)
115{
116	unsigned long paddr;
117
118	pagefault_disable();
119	paddr = page_to_phys(page);
120
121        return __kmap_atomic_primary(1, paddr, 2);
122}
123
124#define __kunmap_atomic_primary(cached, ampr)				\
125do {									\
126	asm volatile("movgs gr0,dampr"#ampr"\n" ::: "memory");		\
127	if (cached)							\
128		asm volatile("movgs gr0,iampr"#ampr"\n" ::: "memory");	\
129} while(0)
130
131#define __kunmap_atomic_secondary(slot, vaddr)				\
132do {									\
133	asm volatile("tlbpr %0,gr0,#4,#1" : : "r"(vaddr) : "memory");	\
134} while(0)
135
136static inline void kunmap_atomic_primary(void *kvaddr)
137{
138        __kunmap_atomic_primary(1, 2);
139	pagefault_enable();
140}
141
142void *kmap_atomic(struct page *page);
143void __kunmap_atomic(void *kvaddr);
144
145#endif /* !__ASSEMBLY__ */
146
147#endif /* __KERNEL__ */
148
149#endif /* _ASM_HIGHMEM_H */