root/arch/arm/mm/proc-v7-2level.S

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * arch/arm/mm/proc-v7-2level.S
   4  *
   5  * Copyright (C) 2001 Deep Blue Solutions Ltd.
   6  */
   7 
   8 #define TTB_S           (1 << 1)
   9 #define TTB_RGN_NC      (0 << 3)
  10 #define TTB_RGN_OC_WBWA (1 << 3)
  11 #define TTB_RGN_OC_WT   (2 << 3)
  12 #define TTB_RGN_OC_WB   (3 << 3)
  13 #define TTB_NOS         (1 << 5)
  14 #define TTB_IRGN_NC     ((0 << 0) | (0 << 6))
  15 #define TTB_IRGN_WBWA   ((0 << 0) | (1 << 6))
  16 #define TTB_IRGN_WT     ((1 << 0) | (0 << 6))
  17 #define TTB_IRGN_WB     ((1 << 0) | (1 << 6))
  18 
  19 /* PTWs cacheable, inner WB not shareable, outer WB not shareable */
  20 #define TTB_FLAGS_UP    TTB_IRGN_WB|TTB_RGN_OC_WB
  21 #define PMD_FLAGS_UP    PMD_SECT_WB
  22 
  23 /* PTWs cacheable, inner WBWA shareable, outer WBWA not shareable */
  24 #define TTB_FLAGS_SMP   TTB_IRGN_WBWA|TTB_S|TTB_NOS|TTB_RGN_OC_WBWA
  25 #define PMD_FLAGS_SMP   PMD_SECT_WBWA|PMD_SECT_S
  26 
  27 /*
  28  *      cpu_v7_switch_mm(pgd_phys, tsk)
  29  *
  30  *      Set the translation table base pointer to be pgd_phys
  31  *
  32  *      - pgd_phys - physical address of new TTB
  33  *
  34  *      It is assumed that:
  35  *      - we are not using split page tables
  36  *
  37  *      Note that we always need to flush BTAC/BTB if IBE is set
  38  *      even on Cortex-A8 revisions not affected by 430973.
  39  *      If IBE is not set, the flush BTAC/BTB won't do anything.
  40  */
  41 ENTRY(cpu_v7_switch_mm)
  42 #ifdef CONFIG_MMU
  43         mmid    r1, r1                          @ get mm->context.id
  44         ALT_SMP(orr     r0, r0, #TTB_FLAGS_SMP)
  45         ALT_UP(orr      r0, r0, #TTB_FLAGS_UP)
  46 #ifdef CONFIG_PID_IN_CONTEXTIDR
  47         mrc     p15, 0, r2, c13, c0, 1          @ read current context ID
  48         lsr     r2, r2, #8                      @ extract the PID
  49         bfi     r1, r2, #8, #24                 @ insert into new context ID
  50 #endif
  51 #ifdef CONFIG_ARM_ERRATA_754322
  52         dsb
  53 #endif
  54         mcr     p15, 0, r1, c13, c0, 1          @ set context ID
  55         isb
  56         mcr     p15, 0, r0, c2, c0, 0           @ set TTB 0
  57         isb
  58 #endif
  59         bx      lr
  60 ENDPROC(cpu_v7_switch_mm)
  61 
  62 /*
  63  *      cpu_v7_set_pte_ext(ptep, pte)
  64  *
  65  *      Set a level 2 translation table entry.
  66  *
  67  *      - ptep  - pointer to level 2 translation table entry
  68  *                (hardware version is stored at +2048 bytes)
  69  *      - pte   - PTE value to store
  70  *      - ext   - value for extended PTE bits
  71  */
  72 ENTRY(cpu_v7_set_pte_ext)
  73 #ifdef CONFIG_MMU
  74         str     r1, [r0]                        @ linux version
  75 
  76         bic     r3, r1, #0x000003f0
  77         bic     r3, r3, #PTE_TYPE_MASK
  78         orr     r3, r3, r2
  79         orr     r3, r3, #PTE_EXT_AP0 | 2
  80 
  81         tst     r1, #1 << 4
  82         orrne   r3, r3, #PTE_EXT_TEX(1)
  83 
  84         eor     r1, r1, #L_PTE_DIRTY
  85         tst     r1, #L_PTE_RDONLY | L_PTE_DIRTY
  86         orrne   r3, r3, #PTE_EXT_APX
  87 
  88         tst     r1, #L_PTE_USER
  89         orrne   r3, r3, #PTE_EXT_AP1
  90 
  91         tst     r1, #L_PTE_XN
  92         orrne   r3, r3, #PTE_EXT_XN
  93 
  94         tst     r1, #L_PTE_YOUNG
  95         tstne   r1, #L_PTE_VALID
  96         eorne   r1, r1, #L_PTE_NONE
  97         tstne   r1, #L_PTE_NONE
  98         moveq   r3, #0
  99 
 100  ARM(   str     r3, [r0, #2048]! )
 101  THUMB( add     r0, r0, #2048 )
 102  THUMB( str     r3, [r0] )
 103         ALT_SMP(W(nop))
 104         ALT_UP (mcr     p15, 0, r0, c7, c10, 1)         @ flush_pte
 105 #endif
 106         bx      lr
 107 ENDPROC(cpu_v7_set_pte_ext)
 108 
 109         /*
 110          * Memory region attributes with SCTLR.TRE=1
 111          *
 112          *   n = TEX[0],C,B
 113          *   TR = PRRR[2n+1:2n]         - memory type
 114          *   IR = NMRR[2n+1:2n]         - inner cacheable property
 115          *   OR = NMRR[2n+17:2n+16]     - outer cacheable property
 116          *
 117          *                      n       TR      IR      OR
 118          *   UNCACHED           000     00
 119          *   BUFFERABLE         001     10      00      00
 120          *   WRITETHROUGH       010     10      10      10
 121          *   WRITEBACK          011     10      11      11
 122          *   reserved           110
 123          *   WRITEALLOC         111     10      01      01
 124          *   DEV_SHARED         100     01
 125          *   DEV_NONSHARED      100     01
 126          *   DEV_WC             001     10
 127          *   DEV_CACHED         011     10
 128          *
 129          * Other attributes:
 130          *
 131          *   DS0 = PRRR[16] = 0         - device shareable property
 132          *   DS1 = PRRR[17] = 1         - device shareable property
 133          *   NS0 = PRRR[18] = 0         - normal shareable property
 134          *   NS1 = PRRR[19] = 1         - normal shareable property
 135          *   NOS = PRRR[24+n] = 1       - not outer shareable
 136          */
 137 .equ    PRRR,   0xff0a81a8
 138 .equ    NMRR,   0x40e040e0
 139 
 140         /*
 141          * Macro for setting up the TTBRx and TTBCR registers.
 142          * - \ttb0 and \ttb1 updated with the corresponding flags.
 143          */
 144         .macro  v7_ttb_setup, zero, ttbr0l, ttbr0h, ttbr1, tmp
 145         mcr     p15, 0, \zero, c2, c0, 2        @ TTB control register
 146         ALT_SMP(orr     \ttbr0l, \ttbr0l, #TTB_FLAGS_SMP)
 147         ALT_UP(orr      \ttbr0l, \ttbr0l, #TTB_FLAGS_UP)
 148         ALT_SMP(orr     \ttbr1, \ttbr1, #TTB_FLAGS_SMP)
 149         ALT_UP(orr      \ttbr1, \ttbr1, #TTB_FLAGS_UP)
 150         mcr     p15, 0, \ttbr1, c2, c0, 1       @ load TTB1
 151         .endm
 152 
 153         /*   AT
 154          *  TFR   EV X F   I D LR    S
 155          * .EEE ..EE PUI. .T.T 4RVI ZWRS BLDP WCAM
 156          * rxxx rrxx xxx0 0101 xxxx xxxx x111 xxxx < forced
 157          *   01    0 110       0011 1100 .111 1101 < we want
 158          */
 159         .align  2
 160         .type   v7_crval, #object
 161 v7_crval:
 162         crval   clear=0x2120c302, mmuset=0x10c03c7d, ucset=0x00c01c7c