Home | History | Annotate | Line # | Download | only in include
      1 /*	$NetBSD: mmu_40.h,v 1.4 2025/07/08 11:45:25 thorpej Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2023 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jason R. Thorpe.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #ifndef _M68K_MMU_40_H_
     33 #define	_M68K_MMU_40_H_
     34 
     35 /*
     36  * Translation table structures for the 68040 MMU.
     37  *
     38  * The 68040 MMU uses a 3-level tree structure.  The root (L1) and
     39  * and pointer (L2) tables contain the base addresses of the tables
     40  * at the lext level, and the page (L3) tables contain the addresses
     41  * of the page descriptors, which may either contain the address of
     42  * a physical page (4K or 8K) directly, or point to an indirect
     43  * descriptor which points to the physical page.
     44  *
     45  * The L1 and L2 tables contain 128 4-byte descriptors, and are thus 512
     46  * bytes in size.  Each of the 128 L1 descriptors corresponds to a 32MB
     47  * region of address space.  Each of the 128 L2 descriptors corresponds
     48  * to a 256KB region of address space.
     49  *
     50  * For 8K pages, the L3 tables contain 32 4-byte descriptors, and are
     51  * thus 128 bytes in size.
     52  *
     53  *  31          25 24          18 17      13 12                       0
     54  * |              |              |          |                          |
     55  *  11111111111111 22222222222222 3333333333 ..........................
     56  *       Root         Pointer        Page               Page
     57  *       Index         Index         Index             Offset
     58  *
     59  * For 4K pages, the L3 tables contain 64 4-byte descriptors, and are
     60  * thus 256 bytes in size.
     61  *
     62  *  31          25 24          18 17        12 11                     0
     63  * |              |              |            |                        |
     64  *  11111111111111 22222222222222 333333333333 ........................
     65  *       Root         Pointer         Page              Page
     66  *       Index         Index          Index            Offset
     67  *
     68  *                       Logical Address Format
     69  */
     70 
     71 #define	LA40_L1_NBITS	7U
     72 #define	LA40_L1_SHIFT	25
     73 #define	LA40_L2_NBITS	7U
     74 #define	LA40_L2_SHIFT	18
     75 #define	LA40_L3_NBITS	(32U - LA40_L1_NBITS - LA40_L2_NBITS - PGSHIFT)
     76 #define	LA40_L3_SHIFT	PGSHIFT
     77 
     78 #define	LA40_L1_COUNT	__BIT(LA40_L1_NBITS)
     79 #define	LA40_L2_COUNT	__BIT(LA40_L2_NBITS)
     80 #define	LA40_L3_COUNT	__BIT(LA40_L3_NBITS)
     81 
     82 #define	LA40_L1_MASK	(__BITS(0,(LA40_L1_NBITS - 1)) << LA40_L1_SHIFT)
     83 #define	LA40_L2_MASK	(__BITS(0,(LA40_L2_NBITS - 1)) << LA40_L2_SHIFT)
     84 #define	LA40_L3_MASK	(__BITS(0,(LA40_L3_NBITS - 1)) << LA40_L3_SHIFT)
     85 
     86 /* N.B. all tables must be aligned to their size */
     87 #define	TBL40_L1_SIZE	(LA40_L1_COUNT * sizeof(uint32_t))
     88 #define	TBL40_L2_SIZE	(LA40_L2_COUNT * sizeof(uint32_t))
     89 #define	TBL40_L3_SIZE	(LA40_L3_COUNT * sizeof(uint32_t))
     90 
     91 #define	LA40_RI(va)	__SHIFTOUT((va), LA40_L1_MASK)	/* root index */
     92 #define	LA40_PI(va)	__SHIFTOUT((va), LA40_L2_MASK)	/* pointer index */
     93 #define	LA40_PGI(va)	__SHIFTOUT((va), LA40_L3_MASK)	/* page index */
     94 
     95 #define	LA40_TRUNC_L1(va) (((vaddr_t)(va)) & LA40_L1_MASK)
     96 #define	LA40_TRUNC_L2(va) (((vaddr_t)(va)) & (LA40_L1_MASK | LA40_L2_MASK))
     97 
     98 /*
     99  * The PTE format for L1 and L2 tables (Upper Tables).
    100  */
    101 #define	UTE40_PTA	__BITS(9,31)	/* Pointer Table Address (L1 PTE) */
    102 					/* Page Table Address (L2 PTE) */
    103 #define	UTE40_PGTA	__BITS(8 - (13 - PGSHIFT),31)
    104 #define	UTE40_U		__BIT(3)	/* Used (referenced) */
    105 #define	UTE40_W		__BIT(2)	/* Write Protected */
    106 #define	UTE40_UDT	__BITS(0,1)	/* Upper Descriptor Type */
    107 					/* 00 or 01 -- Invalid */
    108 					/* 10 or 11 -- Resident */
    109 
    110 #define	UTE40_INVALID	__SHIFTIN(0, UTE_UDT)
    111 #define	UTE40_RESIDENT	__SHIFTIN(2, UTE_UDT)
    112 
    113 /*
    114  * The PTE format for L3 tables.
    115  *
    116  * Some notes:
    117  *
    118  * - PFLUSH variants that specify non-global entries do not invalidate
    119  *   global entries.  If these PFLUSH variants are not used, then the G
    120  *   bit can be used as a software-defined bit.
    121  *
    122  * - The UR bits are "reserved for use by the user", so can be
    123  *   used as software-defined bits.
    124  *
    125  * - The U0 and U1 "User Page Attribute" bits should *not* be used
    126  *   as software-defined bits; they are reflected on the UPA0 and UPA1
    127  *   CPU signals if an external bus transfer results from the access,
    128  *   meaning that they may have system-specific side-effects.
    129  */
    130 #define	PTE40_PGA	__BITS(PGSHIFT,31) /* Page Physical Address */
    131 #define	PTE40_UR_x	__BIT(12)	/* User Reserved (extra avail if 8K) */
    132 #define	PTE40_UR	__BIT(11)	/* User Reserved */
    133 #define	PTE40_G		__BIT(10)	/* Global */
    134 #define	PTE40_U1	__BIT(9)	/* User Page Attribute 1 */
    135 #define	PTE40_U0	__BIT(8)	/* User Page Attribute 0 */
    136 #define	PTE40_S		__BIT(7)	/* Supervisor Protected */
    137 #define	PTE40_CM	__BITS(5,6)	/* Cache Mode */
    138 					/* 00 -- write-through */
    139 					/* 01 -- copy-back */
    140 					/* 10 -- non-cacheable, serialized */
    141 					/* 11 -- non-cacheable */
    142 #define	PTE40_M		__BIT(4)	/* Modified */
    143 #define	PTE40_U		__BIT(3)	/* Used (referenced) */
    144 #define	PTE40_W		__BIT(2)	/* Write Protected */
    145 #define	PTE40_PDT	__BITS(0,1)	/* Page Descriptor Type */
    146 					/* 00       -- Invalid */
    147 					/* 01 or 11 -- Resident */
    148 					/* 10       -- Indirect */
    149 
    150 #define	PTE40_CM_WT	__SHIFTIN(0, PTE40_CM)
    151 #define	PTE40_CM_CB	__SHIFTIN(1, PTE40_CM)
    152 #define	PTE40_CM_NC_SER	__SHIFTIN(2, PTE40_CM)
    153 #define	PTE40_CM_NC	__SHIFTIN(3, PTE40_CM)
    154 
    155 #define	PTE40_INVALID	__SHIFTIN(0, PTE40_PDT)
    156 #define	PTE40_RESIDENT	__SHIFTIN(1, PTE40_PDT)
    157 #define	PTE40_INDIRECT	__SHIFTIN(2, PTE40_PDT)
    158 
    159 /*
    160  * MMU registers (and the sections in the 68040 manual that
    161  * describe them).
    162  */
    163 
    164 /*
    165  * 3.1.1 -- User and Supervisor Root Pointer Registers (32-bit)
    166  *
    167  * URP and SRP contain the physical address of the L1 table for
    168  * user and supervisor space, respectively.  Bits 8-0 of the address
    169  * must be 0.
    170  */
    171 
    172 /*
    173  * 3.1.2 -- Translation Control Register (16-bit)
    174  */
    175 #define	TCR40_E		__BIT(15)	/* enable translation */
    176 #define	TCR40_P		__BIT(14)	/* page size: 0=4K 1=8K */
    177 
    178 /*
    179  * 3.1.3 -- Transparent Translation Registers (32-bit)
    180  *
    181  * There are 2 data translation registers (DTTR0, DTTR1) and 2
    182  * instruction translation registers (ITTR0, ITTR1).
    183  */
    184 #define	TTR40_LAB	__BITS(24,31)	/* logical address base */
    185 #define	TTR40_LAM	__BITS(16,23)	/* logical address mask */
    186 #define	TTR40_E		__BIT(15)	/* enable TTR */
    187 #define	TTR40_SFIELD	__BITS(13,14)	/* Supervisor Mode field (see below) */
    188 #define	TTR40_U1	PTE40_U1
    189 #define	TTR40_U0	PTE40_U0
    190 #define	TTR40_CM	PTE40_CM
    191 #define	TTR40_W		PTE40_W
    192 
    193 #define	TTR40_USER	__SHIFTIN(0, TTR40_SFIELD)
    194 #define	TTR40_SUPER	__SHIFTIN(1, TTR40_SFIELD)
    195 #define	TTR40_BOTH	__SHIFTIN(2, TTR40_SFIELD)
    196 
    197 /*
    198  * 3.1.4 -- MMU Status Register
    199  *
    200  * N.B. If 8K pages are in use, bit 12 of the PA field is **undefined**.
    201  */
    202 #define	MMUSR40_PA	PTE40_PGA
    203 #define	MMUSR40_B	__BIT(11)	/* bus error */
    204 #define	MMUSR40_G	PTE40_G
    205 #define	MMUSR40_U1	PTE40_U1
    206 #define	MMUSR40_U0	PTE40_U0
    207 #define	MMUSR40_S	PTE40_S
    208 #define	MMUSR40_CM	PTE40_CM
    209 #define	MMUSR40_M	PTE40_M
    210 #define	MMUSR40_W	PTE40_W
    211 #define	MMUSR40_T	__BIT(1)	/* Transparent Translation hit */
    212 #define	MMUSR40_R	PTE40_RESIDENT
    213 
    214 #ifdef _KERNEL
    215 /*
    216  * TT register value indices in the mmu_ttregs[] array.  Note that asm
    217  * code makes assumptions about these indices, to change them at your
    218  * peril.
    219  */
    220 extern uint32_t mmu_tt40[];
    221 #define	MMU_TTREG_ITT0	0	/* same order as CPU reg numbers */
    222 #define	MMU_TTREG_ITT1	1
    223 #define	MMU_TTREG_DTT0	2
    224 #define	MMU_TTREG_DTT1	3
    225 #define	MMU_NTTREGS40
    226 
    227 void	mmu_load_urp40(paddr_t);
    228 void	mmu_load_urp60(paddr_t);
    229 void	mmu_load_tt40(uint32_t *);
    230 #endif /* _KERNEL */
    231 
    232 #endif /* _M68K_MMU_40_H_ */
    233