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   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
 115 static inline void *kmap_atomic(struct page *page, enum km_type type)
 116 {
 117         unsigned long paddr;
 118
 119         pagefault_disable();
 120         debug_kmap_atomic(type);
 121         paddr = page_to_phys(page);
 122
 123         switch (type) {
 124         case 0:         return __kmap_atomic_primary(0, paddr, 2);
 125         case 1:         return __kmap_atomic_primary(1, paddr, 3);
 126         case 2:         return __kmap_atomic_primary(2, paddr, 4);
 127         case 3:         return __kmap_atomic_primary(3, paddr, 5);
 128         case 4:         return __kmap_atomic_primary(4, paddr, 6);
 129         case 5:         return __kmap_atomic_primary(5, paddr, 7);
 130         case 6:         return __kmap_atomic_primary(6, paddr, 8);
 131         case 7:         return __kmap_atomic_primary(7, paddr, 9);
 132         case 8:         return __kmap_atomic_primary(8, paddr, 10);
 133
 134         case 9 ... 9 + NR_TLB_LINES - 1:
 135                 return __kmap_atomic_secondary(type - 9, paddr);
 136
 137         default:
 138                 BUG();
 139                 return NULL;
 140         }
 141 }
 142
 143 #define __kunmap_atomic_primary(type, ampr)                             \
 144 do {                                                                    \
 145         asm volatile("movgs gr0,dampr"#ampr"\n" ::: "memory");          \
 146         if (type == __KM_CACHE)                                         \
 147                 asm volatile("movgs gr0,iampr"#ampr"\n" ::: "memory");  \
 148 } while(0)
 149
 150 #define __kunmap_atomic_secondary(slot, vaddr)                          \
 151 do {                                                                    \
 152         asm volatile("tlbpr %0,gr0,#4,#1" : : "r"(vaddr) : "memory");   \
 153 } while(0)
 154
 155 static inline void kunmap_atomic(void *kvaddr, enum km_type type)
 156 {
 157         switch (type) {
 158         case 0:         __kunmap_atomic_primary(0, 2);  break;
 159         case 1:         __kunmap_atomic_primary(1, 3);  break;
 160         case 2:         __kunmap_atomic_primary(2, 4);  break;
 161         case 3:         __kunmap_atomic_primary(3, 5);  break;
 162         case 4:         __kunmap_atomic_primary(4, 6);  break;
 163         case 5:         __kunmap_atomic_primary(5, 7);  break;
 164         case 6:         __kunmap_atomic_primary(6, 8);  break;
 165         case 7:         __kunmap_atomic_primary(7, 9);  break;
 166         case 8:         __kunmap_atomic_primary(8, 10); break;
 167
 168         case 9 ... 9 + NR_TLB_LINES - 1:
 169                 __kunmap_atomic_secondary(type - 9, kvaddr);
 170                 break;
 171
 172         default:
 173                 BUG();
 174         }
 175         pagefault_enable();
 176 }
 177
 178 #endif /* !__ASSEMBLY__ */
 179
 180 #endif /* __KERNEL__ */
 181
 182 #endif /* _ASM_HIGHMEM_H */