arch/m32r/mm/mmu.S

   1 /*
   2  *  linux/arch/m32r/mm/mmu.S
   3  *
   4  *  Copyright (C) 2001 by Hiroyuki Kondo
   5  */
   6
   7 #include <linux/linkage.h>
   8 #include <asm/assembler.h>
   9 #include <asm/smp.h>
  10
  11         .text
  12 #ifdef CONFIG_MMU
  13
  14 #include <asm/mmu_context.h>
  15 #include <asm/page.h>
  16 #include <asm/pgtable.h>
  17 #include <asm/m32r.h>
  18
  19 /*
  20  * TLB Miss Exception handler
  21  */
  22         .balign 16
  23 ENTRY(tme_handler)
  24         .global tlb_entry_i_dat
  25         .global tlb_entry_d_dat
  26
  27         SWITCH_TO_KERNEL_STACK
  28
  29 #if defined(CONFIG_ISA_M32R2)
  30         st      r0, @-sp
  31         st      r1, @-sp
  32         st      r2, @-sp
  33         st      r3, @-sp
  34
  35         seth    r3, #high(MMU_REG_BASE)
  36         ld      r1, @(MESTS_offset, r3) ; r1: status     (MESTS reg.)
  37         ld      r0, @(MDEVP_offset, r3) ; r0: PFN + ASID (MDEVP reg.)
  38         st      r1, @(MESTS_offset, r3) ; clear status   (MESTS reg.)
  39         and3    r1, r1, #(MESTS_IT)
  40         bnez    r1, 1f                  ; instruction TLB miss?
  41
  42 ;; data TLB miss
  43 ;;  input
  44 ;;   r0: PFN + ASID (MDEVP reg.)
  45 ;;   r1 - r3: free
  46 ;;  output
  47 ;;   r0: PFN + ASID
  48 ;;   r1: TLB entry base address
  49 ;;   r2: &tlb_entry_{i|d}_dat
  50 ;;   r3: free
  51
  52 #ifndef CONFIG_SMP
  53         seth    r2, #high(tlb_entry_d_dat)
  54         or3     r2, r2, #low(tlb_entry_d_dat)
  55 #else   /* CONFIG_SMP */
  56         ldi     r1, #-8192
  57         seth    r2, #high(tlb_entry_d_dat)
  58         or3     r2, r2, #low(tlb_entry_d_dat)
  59         and     r1, sp
  60         ld      r1, @(16, r1)           ; current_thread_info->cpu
  61         slli    r1, #2
  62         add     r2, r1
  63 #endif  /* !CONFIG_SMP */
  64         seth    r1, #high(DTLB_BASE)
  65         or3     r1, r1, #low(DTLB_BASE)
  66         bra     2f
  67
  68         .balign 16
  69         .fillinsn
  70 1:
  71 ;; instrucntion TLB miss
  72 ;;  input
  73 ;;   r0: MDEVP reg. (included ASID)
  74 ;;   r1 - r3: free
  75 ;;  output
  76 ;;   r0: PFN + ASID
  77 ;;   r1: TLB entry base address
  78 ;;   r2: &tlb_entry_{i|d}_dat
  79 ;;   r3: free
  80         ldi     r3, #-4096
  81         and3    r0, r0, #(MMU_CONTEXT_ASID_MASK)
  82         mvfc    r1, bpc
  83         and     r1, r3
  84         or      r0, r1                  ; r0: PFN + ASID
  85 #ifndef CONFIG_SMP
  86         seth    r2, #high(tlb_entry_i_dat)
  87         or3     r2, r2, #low(tlb_entry_i_dat)
  88 #else   /* CONFIG_SMP */
  89         ldi     r1, #-8192
  90         seth    r2, #high(tlb_entry_i_dat)
  91         or3     r2, r2, #low(tlb_entry_i_dat)
  92         and     r1, sp
  93         ld      r1, @(16, r1)           ; current_thread_info->cpu
  94         slli    r1, #2
  95         add     r2, r1
  96 #endif  /* !CONFIG_SMP */
  97         seth    r1, #high(ITLB_BASE)
  98         or3     r1, r1, #low(ITLB_BASE)
  99
 100         .fillinsn
 101 2:
 102 ;; select TLB entry
 103 ;;  input
 104 ;;   r0: PFN + ASID
 105 ;;   r1: TLB entry base address
 106 ;;   r2: &tlb_entry_{i|d}_dat
 107 ;;   r3: free
 108 ;;  output
 109 ;;   r0: PFN + ASID
 110 ;;   r1: TLB entry address
 111 ;;   r2, r3: free
 112 #ifdef CONFIG_ISA_DUAL_ISSUE
 113         ld      r3, @r2         ||      srli    r1, #3
 114 #else
 115         ld      r3, @r2
 116         srli    r1, #3
 117 #endif
 118         add     r1, r3
 119         ; tlb_entry_{d|i}_dat++;
 120         addi    r3, #1
 121         and3    r3, r3, #(NR_TLB_ENTRIES - 1)
 122 #ifdef CONFIG_ISA_DUAL_ISSUE
 123         st      r3, @r2         ||      slli    r1, #3
 124 #else
 125         st      r3, @r2
 126         slli    r1, #3
 127 #endif
 128
 129 ;; load pte
 130 ;;  input
 131 ;;   r0: PFN + ASID
 132 ;;   r1: TLB entry address
 133 ;;   r2, r3: free
 134 ;;  output
 135 ;;   r0: PFN + ASID
 136 ;;   r1: TLB entry address
 137 ;;   r2: pte_data
 138 ;;   r3: free
 139         ; pgd = *(unsigned long *)MPTB;
 140         ld24    r2, #(-MPTB - 1)
 141         srl3    r3, r0, #22
 142 #ifdef CONFIG_ISA_DUAL_ISSUE
 143         not     r2, r2              ||  slli    r3, #2  ; r3: pgd offset
 144 #else
 145         not     r2, r2
 146         slli    r3, #2
 147 #endif
 148         ld      r2, @r2                 ; r2: pgd base addr (MPTB reg.)
 149         or      r3, r2                  ; r3: pmd addr
 150
 151         ; pmd = pmd_offset(pgd, address);
 152         ld      r3, @r3                 ; r3: pmd data
 153         ldi     r2, #-4096
 154         beqz    r3, 3f                  ; pmd_none(*pmd) ?
 155
 156         ; pte = pte_offset(pmd, address);
 157         and     r2, r3                  ; r2: pte base addr
 158         srl3    r3, r0, #10
 159         and3    r3, r3, #0xffc          ; r3: pte offset
 160         or      r3, r2
 161         seth    r2, #0x8000
 162         or      r3, r2                  ; r3: pte addr
 163
 164         ; pte_data = (unsigned long)pte_val(*pte);
 165         ld      r2, @r3                 ; r2: pte data
 166         and3    r3, r2, #2              ; _PAGE_PRESENT(=2) check
 167         beqz    r3, 3f
 168
 169         .fillinsn
 170 5:
 171 ;; set tlb
 172 ;;  input
 173 ;;   r0: PFN + ASID
 174 ;;   r1: TLB entry address
 175 ;;   r2: pte_data
 176 ;;   r3: free
 177         st      r0, @r1                 ; set_tlb_tag(entry++, address);
 178         st      r2, @+r1                ; set_tlb_data(entry, pte_data);
 179
 180         .fillinsn
 181 6:
 182         ld      r3, @sp+
 183         ld      r2, @sp+
 184         ld      r1, @sp+
 185         ld      r0, @sp+
 186         rte
 187
 188         .fillinsn
 189 3:
 190 ;; error
 191 ;;  input
 192 ;;   r0: PFN + ASID
 193 ;;   r1: TLB entry address
 194 ;;   r2, r3: free
 195 ;;  output
 196 ;;   r0: PFN + ASID
 197 ;;   r1: TLB entry address
 198 ;;   r2: pte_data
 199 ;;   r3: free
 200 #ifdef CONFIG_ISA_DUAL_ISSUE
 201         bra     5b                  ||  ldi     r2, #2
 202 #else
 203         ldi     r2, #2          ; r2: pte_data = 0 | _PAGE_PRESENT(=2)
 204         bra     5b
 205 #endif
 206
 207 #elif defined (CONFIG_ISA_M32R)
 208
 209         st      sp, @-sp
 210         st      r0, @-sp
 211         st      r1, @-sp
 212         st      r2, @-sp
 213         st      r3, @-sp
 214         st      r4, @-sp
 215
 216         seth    r3, #high(MMU_REG_BASE)
 217         ld      r0, @(MDEVA_offset,r3)  ; r0: address  (MDEVA reg.)
 218         mvfc    r2, bpc                 ; r2: bpc
 219         ld      r1, @(MESTS_offset,r3)  ; r1: status   (MESTS reg.)
 220         st      r1, @(MESTS_offset,r3)  ; clear status (MESTS reg.)
 221         and3    r1, r1, #(MESTS_IT)
 222         beqz    r1, 1f                  ; data TLB miss?
 223
 224 ;; instrucntion TLB miss
 225         mv      r0, r2                  ; address = bpc;
 226         ; entry = (unsigned long *)ITLB_BASE+tlb_entry_i*2;
 227         seth    r3, #shigh(tlb_entry_i_dat)
 228         ld      r4, @(low(tlb_entry_i_dat),r3)
 229         sll3    r2, r4, #3
 230         seth    r1, #high(ITLB_BASE)
 231         or3     r1, r1, #low(ITLB_BASE)
 232         add     r2, r1                  ; r2: entry
 233         addi    r4, #1                  ; tlb_entry_i++;
 234         and3    r4, r4, #(NR_TLB_ENTRIES-1)
 235         st      r4, @(low(tlb_entry_i_dat),r3)
 236         bra     2f
 237         .fillinsn
 238 1:
 239 ;; data TLB miss
 240         ; entry = (unsigned long *)DTLB_BASE+tlb_entry_d*2;
 241         seth    r3, #shigh(tlb_entry_d_dat)
 242         ld      r4, @(low(tlb_entry_d_dat),r3)
 243         sll3    r2, r4, #3
 244         seth    r1, #high(DTLB_BASE)
 245         or3     r1, r1, #low(DTLB_BASE)
 246         add     r2, r1                  ; r2: entry
 247         addi    r4, #1                  ; tlb_entry_d++;
 248         and3    r4, r4, #(NR_TLB_ENTRIES-1)
 249         st      r4, @(low(tlb_entry_d_dat),r3)
 250         .fillinsn
 251 2:
 252 ;; load pte
 253 ; r0: address, r2: entry
 254 ; r1,r3,r4: (free)
 255         ; pgd = *(unsigned long *)MPTB;
 256         ld24    r1, #(-MPTB-1)
 257         not     r1, r1
 258         ld      r1, @r1
 259         srl3    r4, r0, #22
 260         sll3    r3, r4, #2
 261         add     r3, r1                  ; r3: pgd
 262         ; pmd = pmd_offset(pgd, address);
 263         ld      r1, @r3                 ; r1: pmd
 264         beqz    r1, 3f                  ; pmd_none(*pmd) ?
 265 ;
 266         and3    r1, r1, #0xeff
 267         ldi     r4, #611                ; _KERNPG_TABLE(=611)
 268         bne     r1, r4, 3f              ; !pmd_bad(*pmd) ?
 269
 270         .fillinsn
 271 4:
 272         ; pte = pte_offset(pmd, address);
 273         ld      r4, @r3                 ; r4: pte
 274         ldi     r3, #-4096
 275         and     r4, r3
 276         srl3    r3, r0, #10
 277         and3    r3, r3, #0xffc
 278         add     r4, r3
 279         seth    r3, #0x8000
 280         add     r4, r3                  ; r4: pte
 281         ; pte_data = (unsigned long)pte_val(*pte);
 282         ld      r1, @r4                 ; r1: pte_data
 283         and3    r3, r1, #2              ; _PAGE_PRESENT(=2) check
 284         beqz    r3, 3f
 285
 286         .fillinsn
 287 ;; set tlb
 288 ; r0: address, r1: pte_data, r2: entry
 289 ; r3,r4: (free)
 290 5:
 291         ldi     r3, #-4096              ; set_tlb_tag(entry++, address);
 292         and     r3, r0
 293         seth    r4, #shigh(MASID)
 294         ld      r4, @(low(MASID),r4)    ; r4: MASID
 295         and3    r4, r4, #(MMU_CONTEXT_ASID_MASK)
 296         or      r3, r4
 297         st      r3, @r2
 298         st      r1, @(4,r2)             ; set_tlb_data(entry, pte_data);
 299
 300         ld      r4, @sp+
 301         ld      r3, @sp+
 302         ld      r2, @sp+
 303         ld      r1, @sp+
 304         ld      r0, @sp+
 305         ld      sp, @sp+
 306         rte
 307
 308         .fillinsn
 309 3:
 310         ldi     r1, #2                  ; r1: pte_data = 0 | _PAGE_PRESENT(=2)
 311         bra     5b
 312
 313 #else
 314 #error unknown isa configuration
 315 #endif
 316
 317 ENTRY(init_tlb)
 318 ;; Set MMU Register
 319         seth    r0, #high(MMU_REG_BASE)  ; Set MMU_REG_BASE higher
 320         or3     r0, r0, #low(MMU_REG_BASE)  ; Set MMU_REG_BASE lower
 321         ldi     r1, #0
 322         st      r1, @(MPSZ_offset,r0)   ; Set MPSZ Reg(Page size 4KB:0 16KB:1 64KB:2)
 323         ldi     r1, #0
 324         st      r1, @(MASID_offset,r0)  ; Set ASID Zero
 325
 326 ;; Set TLB
 327         seth    r0, #high(ITLB_BASE)    ; Set ITLB_BASE higher
 328         or3     r0, r0, #low(ITLB_BASE) ; Set ITLB_BASE lower
 329         seth    r1, #high(DTLB_BASE)    ; Set DTLB_BASE higher
 330         or3     r1, r1, #low(DTLB_BASE) ; Set DTLB_BASE lower
 331         ldi     r2, #0
 332         ldi     r3, #NR_TLB_ENTRIES
 333         addi    r0, #-4
 334         addi    r1, #-4
 335 clear_tlb:
 336         st      r2, @+r0                ; VPA <- 0
 337         st      r2, @+r0                ; PPA <- 0
 338         st      r2, @+r1                ; VPA <- 0
 339         st      r2, @+r1                ; PPA <- 0
 340         addi    r3, #-1
 341         bnez    r3, clear_tlb
 342 ;;
 343         jmp     r14
 344
 345 ENTRY(m32r_itlb_entrys)
 346 ENTRY(m32r_otlb_entrys)
 347
 348 #endif  /* CONFIG_MMU */
 349
 350         .end