1 /* 2 * pgtsrmmu.h: SRMMU page table defines and code. 3 * 4 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) 5 */ 6 7 #ifndef _SPARC_PGTSRMMU_H 8 #define _SPARC_PGTSRMMU_H 9 10 #include <asm/page.h> 11 12 #ifdef __ASSEMBLY__ 13 #include <asm/thread_info.h> /* TI_UWINMASK for WINDOW_FLUSH */ 14 #endif 15 16 /* Number of contexts is implementation-dependent; 64k is the most we support */ 17 #define SRMMU_MAX_CONTEXTS 65536 18 19 /* PMD_SHIFT determines the size of the area a second-level page table entry can map */ 20 #define SRMMU_REAL_PMD_SHIFT 18 21 #define SRMMU_REAL_PMD_SIZE (1UL << SRMMU_REAL_PMD_SHIFT) 22 #define SRMMU_REAL_PMD_MASK (~(SRMMU_REAL_PMD_SIZE-1)) 23 #define SRMMU_REAL_PMD_ALIGN(__addr) (((__addr)+SRMMU_REAL_PMD_SIZE-1)&SRMMU_REAL_PMD_MASK) 24 25 /* PGDIR_SHIFT determines what a third-level page table entry can map */ 26 #define SRMMU_PGDIR_SHIFT 24 27 #define SRMMU_PGDIR_SIZE (1UL << SRMMU_PGDIR_SHIFT) 28 #define SRMMU_PGDIR_MASK (~(SRMMU_PGDIR_SIZE-1)) 29 #define SRMMU_PGDIR_ALIGN(addr) (((addr)+SRMMU_PGDIR_SIZE-1)&SRMMU_PGDIR_MASK) 30 31 #define SRMMU_REAL_PTRS_PER_PTE 64 32 #define SRMMU_REAL_PTRS_PER_PMD 64 33 #define SRMMU_PTRS_PER_PGD 256 34 35 #define SRMMU_REAL_PTE_TABLE_SIZE (SRMMU_REAL_PTRS_PER_PTE*4) 36 #define SRMMU_PMD_TABLE_SIZE (SRMMU_REAL_PTRS_PER_PMD*4) 37 #define SRMMU_PGD_TABLE_SIZE (SRMMU_PTRS_PER_PGD*4) 38 39 /* 40 * To support pagetables in highmem, Linux introduces APIs which 41 * return struct page* and generally manipulate page tables when 42 * they are not mapped into kernel space. Our hardware page tables 43 * are smaller than pages. We lump hardware tabes into big, page sized 44 * software tables. 45 * 46 * PMD_SHIFT determines the size of the area a second-level page table entry 47 * can map, and our pmd_t is 16 times larger than normal. The values which 48 * were once defined here are now generic for 4c and srmmu, so they're 49 * found in pgtable.h. 50 */ 51 #define SRMMU_PTRS_PER_PMD 4 52 53 /* Definition of the values in the ET field of PTD's and PTE's */ 54 #define SRMMU_ET_MASK 0x3 55 #define SRMMU_ET_INVALID 0x0 56 #define SRMMU_ET_PTD 0x1 57 #define SRMMU_ET_PTE 0x2 58 #define SRMMU_ET_REPTE 0x3 /* AIEEE, SuperSparc II reverse endian page! */ 59 60 /* Physical page extraction from PTP's and PTE's. */ 61 #define SRMMU_CTX_PMASK 0xfffffff0 62 #define SRMMU_PTD_PMASK 0xfffffff0 63 #define SRMMU_PTE_PMASK 0xffffff00 64 65 /* The pte non-page bits. Some notes: 66 * 1) cache, dirty, valid, and ref are frobbable 67 * for both supervisor and user pages. 68 * 2) exec and write will only give the desired effect 69 * on user pages 70 * 3) use priv and priv_readonly for changing the 71 * characteristics of supervisor ptes 72 */ 73 #define SRMMU_CACHE 0x80 74 #define SRMMU_DIRTY 0x40 75 #define SRMMU_REF 0x20 76 #define SRMMU_NOREAD 0x10 77 #define SRMMU_EXEC 0x08 78 #define SRMMU_WRITE 0x04 79 #define SRMMU_VALID 0x02 /* SRMMU_ET_PTE */ 80 #define SRMMU_PRIV 0x1c 81 #define SRMMU_PRIV_RDONLY 0x18 82 83 #define SRMMU_CHG_MASK (0xffffff00 | SRMMU_REF | SRMMU_DIRTY) 84 85 /* SRMMU swap entry encoding 86 * 87 * We use 5 bits for the type and 19 for the offset. This gives us 88 * 32 swapfiles of 4GB each. Encoding looks like: 89 * 90 * oooooooooooooooooootttttRRRRRRRR 91 * fedcba9876543210fedcba9876543210 92 * 93 * The bottom 7 bits are reserved for protection and status bits, especially 94 * PRESENT. 95 */ 96 #define SRMMU_SWP_TYPE_MASK 0x1f 97 #define SRMMU_SWP_TYPE_SHIFT 7 98 #define SRMMU_SWP_OFF_MASK 0xfffff 99 #define SRMMU_SWP_OFF_SHIFT (SRMMU_SWP_TYPE_SHIFT + 5) 100 101 /* Some day I will implement true fine grained access bits for 102 * user pages because the SRMMU gives us the capabilities to 103 * enforce all the protection levels that vma's can have. 104 * XXX But for now... 105 */ 106 #define SRMMU_PAGE_NONE __pgprot(SRMMU_CACHE | \ 107 SRMMU_PRIV | SRMMU_REF) 108 #define SRMMU_PAGE_SHARED __pgprot(SRMMU_VALID | SRMMU_CACHE | \ 109 SRMMU_EXEC | SRMMU_WRITE | SRMMU_REF) 110 #define SRMMU_PAGE_COPY __pgprot(SRMMU_VALID | SRMMU_CACHE | \ 111 SRMMU_EXEC | SRMMU_REF) 112 #define SRMMU_PAGE_RDONLY __pgprot(SRMMU_VALID | SRMMU_CACHE | \ 113 SRMMU_EXEC | SRMMU_REF) 114 #define SRMMU_PAGE_KERNEL __pgprot(SRMMU_VALID | SRMMU_CACHE | SRMMU_PRIV | \ 115 SRMMU_DIRTY | SRMMU_REF) 116 117 /* SRMMU Register addresses in ASI 0x4. These are valid for all 118 * current SRMMU implementations that exist. 119 */ 120 #define SRMMU_CTRL_REG 0x00000000 121 #define SRMMU_CTXTBL_PTR 0x00000100 122 #define SRMMU_CTX_REG 0x00000200 123 #define SRMMU_FAULT_STATUS 0x00000300 124 #define SRMMU_FAULT_ADDR 0x00000400 125 126 #define WINDOW_FLUSH(tmp1, tmp2) \ 127 mov 0, tmp1; \ 128 98: ld [%g6 + TI_UWINMASK], tmp2; \ 129 orcc %g0, tmp2, %g0; \ 130 add tmp1, 1, tmp1; \ 131 bne 98b; \ 132 save %sp, -64, %sp; \ 133 99: subcc tmp1, 1, tmp1; \ 134 bne 99b; \ 135 restore %g0, %g0, %g0; 136 137 #ifndef __ASSEMBLY__ 138 extern unsigned long last_valid_pfn; 139 140 /* This makes sense. Honest it does - Anton */ 141 /* XXX Yes but it's ugly as sin. FIXME. -KMW */ 142 extern void *srmmu_nocache_pool; 143 #define __nocache_pa(VADDR) (((unsigned long)VADDR) - SRMMU_NOCACHE_VADDR + __pa((unsigned long)srmmu_nocache_pool)) 144 #define __nocache_va(PADDR) (__va((unsigned long)PADDR) - (unsigned long)srmmu_nocache_pool + SRMMU_NOCACHE_VADDR) 145 #define __nocache_fix(VADDR) __va(__nocache_pa(VADDR)) 146 147 /* Accessing the MMU control register. */ 148 unsigned int srmmu_get_mmureg(void); 149 void srmmu_set_mmureg(unsigned long regval); 150 void srmmu_set_ctable_ptr(unsigned long paddr); 151 void srmmu_set_context(int context); 152 int srmmu_get_context(void); 153 unsigned int srmmu_get_fstatus(void); 154 unsigned int srmmu_get_faddr(void); 155 156 /* This is guaranteed on all SRMMU's. */ 157 static inline void srmmu_flush_whole_tlb(void) 158 { 159 __asm__ __volatile__("sta %%g0, [%0] %1\n\t": : 160 "r" (0x400), /* Flush entire TLB!! */ 161 "i" (ASI_M_FLUSH_PROBE) : "memory"); 162 163 } 164 165 static inline int 166 srmmu_get_pte (unsigned long addr) 167 { 168 register unsigned long entry; 169 170 __asm__ __volatile__("\n\tlda [%1] %2,%0\n\t" : 171 "=r" (entry): 172 "r" ((addr & 0xfffff000) | 0x400), "i" (ASI_M_FLUSH_PROBE)); 173 return entry; 174 } 175 176 #endif /* !(__ASSEMBLY__) */ 177 178 #endif /* !(_SPARC_PGTSRMMU_H) */ 179