/*-
* Copyright (c) 1997 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jeremy Cooper.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This file contains the machine-independent definitions
* related to the Motorola MC68851 Memory Management Unit (MMU).
* Things that depend on the contents of the Translation Control
* (TC) register are in <machine/pte.h>.
*/
#ifndef _SUN3X_MC68851_H
#define _SUN3X_MC68851_H
/**************************** MMU STRUCTURES ****************************
* MMU structures define the format of data used by the MC68851. *
************************************************************************
** MC68851 Root Pointer
* All address translations begin with the examination of the value
* in the MC68851 Root Pointer register. It describes the base address
* (in physical memory) of the root table to be used as well as any limits
* to the address range it supports. Its structure is identical to a Long
* Format Table Descriptor (described below.)
*/
struct mmu_rootptr {
u_long rp_attr; /* Lower/Upper Limit and access flags */
u_long rp_addr; /* Physical Base Address */
};
typedef struct mmu_rootptr mmu_rootptr_t;
/** MC68851 Long Format Table Descriptor
* The root table for a sun3x pmap is a 128 element array of 'long format
* table descriptors'. The structure of a long format table descriptor is:
*
* 63 48
* +---+---.---.---.---.---.---.---.---.---.---.---.---.---.---.---+
* |L/U| LIMIT |
* +---+---.---+---.---.---+---+---+---+---+---+---+---+---+---.---+
* | RAL | WAL |SG | S | 0 | 0 | 0 | 0 | U |WP |DT (10)|
* +---.---.---+---.---.---+---+---+---+---+---+---+---+---+---.---+
* | TABLE PHYSICAL ADDRESS (BITS 31-16) |
* +---.---.---.---.---.---.---.---.---.---.---.---+---.---.---.---+
* | TABLE PHYSICAL ADDRESS (15-4) | UNUSED |
* +---.---.---.---.---.---.---.---.---.---.---.---+---.---.---.---+
* 15 0
*
* Note: keep the unused bits set to zero so that no masking of the
* base address is needed.
*/
struct mmu_long_dte_struct { /* 'dte' stands for 'descriptor table entry' */
union {
struct {
char lu_flag:1; /* Lower/Upper Limit flag */
int limit:15; /* Table Size limit */
char ral:3; /* Read Access Level */
char wal:3; /* Write Access Level */
char sg:1; /* Shared Globally flag */
char supv:1; /* Supervisor Only flag */
char rsvd:4; /* Reserved (All zeros) */
char u:1; /* Used flag */
char wp:1; /* Write Protect flag */
char dt:2; /* Descriptor Type */
/* Bit masks for fields above */
#define MMU_LONG_DTE_LU 0x80000000
#define MMU_LONG_DTE_LIMIT 0x7fff0000
#define MMU_LONG_DTE_RAL 0x0000e000
#define MMU_LONG_DTE_WAL 0x00001c00
#define MMU_LONG_DTE_SG 0x00000200
#define MMU_LONG_DTE_SUPV 0x00000100
#define MMU_LONG_DTE_USED 0x00000008
#define MMU_LONG_DTE_WP 0x00000004
#define MMU_LONG_DTE_DT 0x00000003
} attr_struct;
u_long raw; /* struct above, addressable as a long */
} attr;
union {
struct {
int base_addr:28; /* Physical base address
char unused:4; * of the table pointed to
* by this entry.
*/
/* Bit masks for fields above */
#define MMU_LONG_DTE_BASEADDR 0xfffffff0
} addr_struct;
u_long raw; /* struct above, addressable as a long */
} addr;
};
typedef struct mmu_long_dte_struct mmu_long_dte_t;
typedef struct mmu_long_dte_struct *mmu_long_dtbl_t;
/** MC68851 Long Format Page Descriptor
* Although not likely to be used in this implementation, a level
* 'A' table may contain long format PAGE descriptors. A long format
* page descriptor is the same size as a long format table descriptor.
* Its discriminating feature to the MMU is its descriptor field: 01.
* 63 48
* +---.---.---.---.---.---.---.---.---.---.---.---.---.---.---.---+
* | UNUSED |
* +---.---.---+---.---.---+---+---+---+---+---+---+---+---+---.---+
* | RAL | WAL |SG | S | G |CI | L | M | U |WP |DT (01)|
* +---.---.---+---.---.---+---+---+---+---+---+---+---+---+---.---+
* | TABLE PHYSICAL ADDRESS (BITS 31-16) |
* +---.---.---.---.---.---.---.---.---.---.---.---.---.---.---.---+
* |TABLE PHYS. ADDRESS (15-8) | UNUSED |
* +---.---.---.---.---.---.---.---.---.---.---.---.---.---.---.---+
* 15 0
*/
struct mmu_long_pte_struct { /* 'pte' stands for 'page table entry' */
union {
struct {
int unused:16; /* Unused */
char ral:3; /* Read Access Level */
char wal:3; /* Write Access Level */
char sg:1; /* Shared Globally flag */
char supv:1; /* Supervisor Only flag */
char g:1; /* Gate allowed */
char ci:1; /* Cache inhibit */
char l:1; /* Lock entry */
char m:1; /* Modified flag */
char u:1; /* Used flag */
char wp:1; /* Write Protect flag */
char dt:2; /* Descriptor Type */
/* Bit masks for fields above */
#define MMU_LONG_PTE_RAL 0x0000e000
#define MMU_LONG_PTE_WAL 0x00001c00
#define MMU_LONG_PTE_SG 0x00000200
#define MMU_LONG_PTE_SUPV 0x00000100
#define MMU_LONG_PTE_GATE 0x00000080
#define MMU_LONG_PTE_CI 0x00000040
#define MMU_LONG_PTE_LOCK 0x00000020
#define MMU_LONG_PTE_M 0x00000010
#define MMU_LONG_PTE_USED 0x00000008
#define MMU_LONG_PTE_WP 0x00000004
#define MMU_LONG_PTE_DT 0x00000003
} attr_struct;
u_long raw; /* struct above, addressable as a long */
} attr;
union {
struct {
long base_addr:24; /* Physical base address
char unused:8; * of page this entry
* points to.
*/
/* Bit masks for fields above */
#define MMU_LONG_PTE_BASEADDR 0xffffff00
} addr_struct;
u_long raw; /* struct above, addressable as a long */
} addr;
};
typedef struct mmu_long_pte_struct mmu_long_pte_t;
typedef struct mmu_long_pte_struct *mmu_long_ptbl_t;
/* Every entry in the level A table (except for the page entries
* described above) points to a level B table. Level B tables are
* arrays of 'short format' table descriptors. Their structure
* is smaller than an A table descriptor and is as follows:
*
* 31 16
* +---.---.---.---.---.---.---.---.---.---.---.---.---.---.---.---+
* | TABLE PHYSICAL BASE ADDRESS (BITS 31-16) |
* +---.---.---.---.---.---.---.---.---.---.---.---+---+---+---.---+
* | TABLE PHYSICAL BASE ADDRESS (15-4) | U |WP |DT (10)|
* +---.---.---.---.---.---.---.---.---.---.---.---+---+---+---.---+
* 15 0
*/
struct mmu_short_dte_struct { /* 'dte' stands for 'descriptor table entry' */
union {
struct {
long base_addr:28;
char u:1;
char wp:1;
char dt:2;
#define MMU_SHORT_DTE_BASEADDR 0xfffffff0
#define MMU_SHORT_DTE_USED 0x00000008
#define MMU_SHORT_DTE_WP 0x00000004
#define MMU_SHORT_DTE_DT 0x00000003
} attr_struct;
u_long raw;
} attr;
};
typedef struct mmu_short_dte_struct mmu_short_dte_t;
typedef struct mmu_short_dte_struct *mmu_short_dtbl_t;
/* Every entry in a level B table points to a level C table. Level C tables
* contain arrays of short format page 'entry' descriptors. A short format
* page 'entry' is the same size as a short format page 'table'
* descriptor (a B table entry). Thus B and C tables can be allocated
* interchangeably from the same pool. However, we will keep them separate.
*
* The descriptor type (DT) field of a Page Table Entry (PTE) is '01'. This
* indicates to the MMU that the address contained in the PTE's 'base
* address' field is the base address for a physical page in memory to which
* the VA should be mapped, and not a base address for a yet another
* descriptor table, thus ending the table walk.
*
* 31 16
* +---.---.---.---.---.---.---.---.---.---.---.---.---.---.---.---+
* | TABLE PHYSICAL BASE ADDRESS (BITS 31-16) |
* +---.---.---.---.---.---.---.---+---+---+---+---+---+---+---.---+
* |TABLE PHYS. BASE ADDRESS (15-8)| G |CI | L | M | U |WP |DT (10)|
* +---.---.---.---.---.---.---.---+---+---+---+---+---+---+---.---+
* 15 0
*/
struct mmu_short_pte_struct { /* 'pte' stands for 'page table entry' */
union {
struct {
long base_addr:24;
char g:1;
char ci:1;
char l:1;
char m:1;
char u:1;
char wp:1;
char dt:2;
#define MMU_SHORT_PTE_BASEADDR 0xffffff00
#define MMU_SHORT_PTE_UN2 0x00000080
#define MMU_SHORT_PTE_CI 0x00000040
#define MMU_SHORT_PTE_UN1 0x00000020
#define MMU_SHORT_PTE_M 0x00000010
#define MMU_SHORT_PTE_USED 0x00000008
#define MMU_SHORT_PTE_WP 0x00000004
#define MMU_SHORT_PTE_DT 0x00000003
} attr_struct;
u_long raw;
} attr;
};
typedef struct mmu_short_pte_struct mmu_short_pte_t;
typedef struct mmu_short_pte_struct *mmu_short_ptbl_t;
/* These are bit masks and other values that are common to all types of
* descriptors.
*/
/* Page table descriptors have a 'Descriptor Type' field describing the
* format of the tables they point to. It is two bits wide and is one of:
*/
#define MMU_DT_INVALID 0x0 /* Invalid descriptor entry */
#define MMU_DT_PAGE 0x1 /* Descriptor describes a page entry */
#define MMU_DT_SHORT 0x2 /* describes a short format table */
#define MMU_DT_LONG 0x3 /* describes a long format table */
#define MMU_DT_MASK 0x00000003 /* Bit location of the DT field */
/* Various macros for manipulating and setting MMU descriptor
* characteristics.
*/
/* returns true if a descriptor is valid. */
#define MMU_VALID_DT(dte) ((dte).attr.raw & MMU_DT_MASK)
/* returns true if a descriptor is invalid */
#define MMU_INVALID_DT(dte) (!((dte).attr.raw & MMU_DT_MASK))
/* returns true if a descriptor has been referenced */
#define MMU_PTE_USED(pte) ((pte).attr.raw & MMU_SHORT_PTE_USED)
/* returns true if a descriptor has been modified */
#define MMU_PTE_MODIFIED(pte) ((pte).attr.raw & MMU_SHORT_PTE_M)
/* extracts the physical address from a pte */
#define MMU_PTE_PA(pte) ((pte).attr.raw & MMU_SHORT_PTE_BASEADDR)
/* extracts the physical address from a dte */
#define MMU_DTE_PA(dte) ((dte).attr.raw & MMU_SHORT_DTE_BASEADDR)
