comrogue-pi/include/comrogue/internals/mmu.h
2013-04-23 01:49:58 -06:00

301 lines
15 KiB
C

/*
* This file is part of the COMROGUE Operating System for Raspberry Pi
*
* Copyright (c) 2013, Eric J. Bowersox / Erbosoft Enterprises
* All rights reserved.
*
* This program is free for commercial and non-commercial use as long as the following conditions are
* adhered to.
*
* Copyright in this file remains Eric J. Bowersox and/or Erbosoft, and as such any copyright notices
* in the code are not to be removed.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted
* provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this list of conditions and
* the following disclaimer.
* * 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
*
* "Raspberry Pi" is a trademark of the Raspberry Pi Foundation.
*/
#ifndef __MMU_H_INCLUDED
#define __MMU_H_INCLUDED
#ifdef __COMROGUE_INTERNALS__
/*----------------------------------------------
* BCM2835 ARM Memory Management Unit constants
*----------------------------------------------
*/
/* Memory system constants */
#define SYS_PAGE_SIZE 4096 /* standard page size for normal page */
#define SYS_PAGE_BITS 12 /* log2(SYS_PAGE_SIZE), number of bits in a page address */
#define SYS_TTB0_SIZE 8192 /* TTB0 must be located on this boundary and is this size */
#define SYS_TTB0_ENTRIES 2048 /* SYS_TTB0_SIZE/4, number of entries in TTB0 */
#define SYS_TTB1_SIZE 16384 /* TTB1 must be located on this boundary and is this size */
#define SYS_TTB1_ENTRIES 4096 /* SYS_TTB1_SIZE/4, number of entries in TTB1 */
#define SYS_TTB_BITS 12 /* log2(SYS_TTB1_SIZE/4), number of bits in a TTB address */
#define SYS_SEC_SIZE 1048576 /* standard section size */
#define SYS_SEC_BITS 20 /* number of bits in a section address */
#define SYS_SEC_PAGES 256 /* SYS_SEC_SIZE/SYS_PAGE_SIZE, number of pages equivalent to a section */
#define SYS_PGTBL_SIZE 1024 /* page tables must be located on this boundary and are this size */
#define SYS_PGTBL_BITS 8 /* log2(SYS_PGTBL_SIZE/4), number of bits in a page table address */
#define SYS_PGTBL_ENTRIES 256 /* SYS_PGTBL_SIZE/4, number of entries in a page table */
/* Section descriptor bits */
#define TTBSEC_PXN 0x00000001 /* Privileged Execute-Never */
#define TTBSEC_ALWAYS 0x00000002 /* this bit must always be set for a section */
#define TTBSEC_B 0x00000004 /* memory region attribute bit */
#define TTBSEC_C 0x00000008 /* memory region attribute bit */
#define TTBSEC_XN 0x00000010 /* Execute-Never */
#define TTBSEC_DOM_MASK 0x000001E0 /* domain indicator */
#define TTBSEC_P 0x00000200 /* ECC enabled (not supported) */
#define TTBSEC_AP 0x00000C00 /* access permission bits */
#define TTBSEC_TEX 0x00007000 /* memory type flags */
#define TTBSEC_APX 0x00008000 /* access permission extended */
#define TTBSEC_S 0x00010000 /* Shared */
#define TTBSEC_NG 0x00020000 /* Not Global */
#define TTBSEC_SUPER 0x00040000 /* Set for supersections */
#define TTBSEC_NS 0x00080000 /* Not Secure */
#define TTBSEC_ALLFLAGS 0x000FFFFF /* "all flags" mask */
#define TTBSEC_BASE 0xFFF00000 /* section base address mask */
#define TTBSEC_SBASE 0xFF000000 /* supersection base address mask */
#define TTBSEC_SBASEHI 0x00F00000 /* supersection high base address mask */
/* AP bits for the standard access control model */
#define TTBSEC_AP00 0x00000000 /* no access */
#define TTBSEC_AP01 0x00000400 /* supervisor only access */
#define TTBSEC_AP10 0x00000800 /* user read-only access */
#define TTBSEC_AP11 0x00000C00 /* user read-write access */
/* AP bits for the simplified access control model */
#define TTBSEC_ACCESS 0x00000400 /* Accessed bit */
#define TTBSEC_AP_PL0 0x00000800 /* enable access at PL0 */
#define TTBSEC_AP_RO TTBSEC_APX /* read-only access */
/* Page table descriptor bits */
#define TTBPGTBL_ALWAYS 0x00000001 /* bottom-two bits are always this */
#define TTBPGTBL_PXN 0x00000004 /* Privileged Execute-Never */
#define TTBPGTBL_NS 0x00000008 /* Not Secure */
#define TTBPGTBL_DOM_MASK 0x000001E0 /* domain indicator */
#define TTBPGTBL_P 0x00000200 /* ECC enabled (not supported) */
#define TTBPGTBL_ALLFLAGS 0x000003FF /* "all flags" mask */
#define TTBPGTBL_BASE 0xFFFFFC00 /* page table base address mask */
/* Bits to query the type of TTB entry we're looking at */
#define TTBQUERY_MASK 0x00000003 /* bits we can query */
#define TTBQUERY_FAULT 0x00000000 /* indicates a fault */
#define TTBQUERY_PGTBL 0x00000001 /* indicates a page table */
#define TTBQUERY_SEC 0x00000002 /* indicates a section */
#define TTBQUERY_PXNSEC 0x00000003 /* indicates a section with PXN (or reserved) */
/* TTB auxiliary descriptor bits */
#define TTBAUX_SACRED 0x00000001 /* sacred entry, do not deallocate */
#define TTBAUX_UNWRITEABLE 0x00000002 /* entry unwriteable */
/* Small page table entry bits */
#define PGTBLSM_XN 0x00000001 /* Execute-Never */
#define PGTBLSM_ALWAYS 0x00000002 /* this bit must always be set for a page table entry */
#define PGTBLSM_B 0x00000004 /* memory region attribute bit */
#define PGTBLSM_C 0x00000008 /* memory region attribute bit */
#define PGTBLSM_AP 0x00000030 /* access permission bits */
#define PGTBLSM_TEX 0x000001C0 /* memory type flags */
#define PGTBLSM_APX 0x00000200 /* access permission extended */
#define PGTBLSM_S 0x00000400 /* Shared */
#define PGTBLSM_NG 0x00000800 /* Not Global */
#define PGTBLSM_PAGE 0xFFFFF000 /* page base address mask */
/* AP bits for the standard access control model */
#define PGTBLSM_AP00 0x00000000 /* no access */
#define PGTBLSM_AP01 0x00000010 /* supervisor only access */
#define PGTBLSM_AP10 0x00000020 /* user read-only access */
#define PGTBLSM_AP11 0x00000030 /* user read-write access */
/* Bits to query the type of page table entry we're looking at */
#define PGQUERY_MASK 0x00000003 /* bits we can query */
#define PGQUERY_FAULT 0x00000000 /* indicates a fault */
#define PGQUERY_LG 0x00000001 /* large page (64K) */
#define PGQUERY_SM 0x00000002 /* small page (4K) */
#define PGQUERY_SM_XN 0x00000003 /* small page with Execute-Never set */
/* Page auxiliary descriptor bits */
#define PGAUX_SACRED 0x00000001 /* sacred entry, do not deallocate */
#define PGAUX_UNWRITEABLE 0x00000002 /* entry unwriteable */
/* Combinations of flags we use regularly. */
#define TTBFLAGS_LIB_CODE TTBPGTBL_ALWAYS
#define PGTBLFLAGS_LIB_CODE (PGTBLSM_ALWAYS | PGTBLSM_B | PGTBLSM_C | PGTBLSM_AP10)
#define PGAUXFLAGS_LIB_CODE (PGAUX_SACRED | PGAUX_UNWRITEABLE)
#define TTBFLAGS_KERNEL_CODE TTBPGTBL_ALWAYS
#define PGTBLFLAGS_KERNEL_CODE (PGTBLSM_ALWAYS | PGTBLSM_B | PGTBLSM_C | PGTBLSM_AP01)
#define PGAUXFLAGS_KERNEL_CODE (PGAUX_SACRED | PGAUX_UNWRITEABLE)
#define TTBFLAGS_KERNEL_DATA TTBPGTBL_ALWAYS
#define PGTBLFLAGS_KERNEL_DATA (PGTBLSM_XN | PGTBLSM_ALWAYS | PGTBLSM_B | PGTBLSM_C | PGTBLSM_AP01)
#define PGAUXFLAGS_KERNEL_DATA PGAUX_SACRED
#define TTBFLAGS_INIT_CODE TTBFLAGS_KERNEL_CODE
#define PGTBLFLAGS_INIT_CODE PGTBLFLAGS_KERNEL_CODE
#define PGAUXFLAGS_INIT_CODE PGAUX_UNWRITEABLE
#define TTBFLAGS_INIT_DATA TTBFLAGS_KERNEL_DATA
#define PGTBLFLAGS_INIT_DATA PGTBLFLAGS_KERNEL_DATA
#define PGAUXFLAGS_INIT_DATA 0
#define TTBFLAGS_MMIO TTBPGTBL_ALWAYS
#define PGTBLFLAGS_MMIO (PGTBLSM_ALWAYS | PGTBLSM_AP01)
#define PGAUXFLAGS_MMIO PGAUX_SACRED
#define TTBAUXFLAGS_PAGETABLE 0
#ifndef __ASM__
/*-------------------------------------------------------
* Data structures defining the TTB and page table data.
*-------------------------------------------------------
*/
/* TTB fault descriptor */
typedef struct tagTTBFAULT {
unsigned always0 : 2; /* bits are always 0 for a fault entry */
unsigned ignored : 30; /* ignored (COMROGUE may define these later) */
} TTBFAULT, *PTTBFAULT;
/* TTB page table descriptor */
typedef struct tagTTBPGTBL {
unsigned always01 : 2; /* bits are always 01 for a page table */
unsigned pxn : 1; /* Privileged Execute-Never bit */
unsigned ns : 1; /* Not Secure bit */
unsigned always0 : 1; /* bit is always 0 for a page table */
unsigned domain : 4; /* protection domain */
unsigned p : 1; /* not supported, should be 0 */
unsigned baseaddr : 22; /* upper 22 bits of base address of page table */
} TTBPGTBL, *PTTBPGTBL;
/* TTB section descriptor */
typedef struct tagTTBSEC {
unsigned pxn : 1; /* Privileged Execute-Never bit */
unsigned always1: 1; /* bit is always 1 for a section */
unsigned b : 1; /* attribute bit ("Buffered") */
unsigned c : 1; /* attribute bit ("Cached") */
unsigned xn : 1; /* Execute-Never bit */
unsigned domain : 4; /* protection domain */
unsigned p : 1; /* not supported, should be 0 */
unsigned ap : 2; /* access permissions */
unsigned tex : 3; /* memory type flags */
unsigned ap2 : 1; /* access permission extension */
unsigned s : 1; /* Shared bit */
unsigned ng : 1; /* Not Global bit */
unsigned always0 : 1; /* bit is always 0 for a section */
unsigned ns : 1; /* Not Secure bit */
unsigned baseaddr : 12; /* upper 12 bits of base address of section */
} TTBSEC, *PTTBSEC;
/* Single TTB entry descriptor */
typedef union tagTTB {
UINT32 data; /* raw data for entry */
TTBFAULT fault; /* "fault" data */
TTBPGTBL pgtbl; /* page table data */
TTBSEC sec; /* 1Mb section data */
} TTB, *PTTB;
/* TTB auxiliary descriptor */
typedef struct tagTTBAUXENTRY {
unsigned sacred : 1; /* sacred TTB - should never be deallocated */
unsigned unwriteable : 1; /* entry is not writeable */
unsigned reserved : 30; /* reserved for future allocation */
} TTBAUXENTRY, *PTTBAUXENTRY;
/* TTB auxiliary table entry */
typedef union tagTTBAUX {
UINT32 data; /* raw data for entry */
TTBAUXENTRY aux; /* aux entry itself */
} TTBAUX, *PTTBAUX;
/* page table descriptor for a fault entry */
typedef struct tagPGTBLFAULT {
unsigned always0 : 2; /* bits are always 0 for a fault entry */
unsigned ignored : 30; /* ignored (COMROGUE may define these later) */
} PGTBLFAULT, *PPGTBLFAULT;
/* page table descriptor for regular 4K pages */
typedef struct tagPGTBLSM {
unsigned xn : 1; /* Execute Never */
unsigned always1 : 1; /* always 1 for a 4k small page */
unsigned b : 1; /* attribute bit ("Buffered") */
unsigned c : 1; /* attribute bit ("Cached") */
unsigned ap : 2; /* access permissions */
unsigned tex : 3; /* memory type flags */
unsigned apx : 1; /* access permission extension */
unsigned s : 1; /* Shared bit */
unsigned ng : 1; /* Not Global bit */
unsigned pgaddr : 20; /* upper 20 bits of base address of page */
} PGTBLSM, *PPGTBLSM;
/* single page table entry */
typedef union tagPGTBL {
UINT32 data; /* raw data for entry */
PGTBLFAULT fault; /* "fault" data */
PGTBLSM pg; /* small page descriptor */
} PGTBL, *PPGTBL;
/* page auxiliary descriptor */
typedef struct tagPGAUXENTRY {
unsigned sacred : 1; /* sacred page - should never be deallocated */
unsigned unwriteable : 1; /* entry is not writeable */
unsigned reserved : 30; /* reserved for future allocation */
} PGAUXENTRY, *PPGAUXENTRY;
/* page table auxiliary entry */
typedef union tagPGAUX {
UINT32 data; /* raw data for entry */
PGAUXENTRY aux; /* the auxiliary entry itself */
} PGAUX, *PPGAUX;
/* complete structure of a page table, hardware + auxiliary */
typedef struct tagPAGETAB {
PGTBL pgtbl[SYS_PGTBL_ENTRIES]; /* hardware page table entries */
PGAUX pgaux[SYS_PGTBL_ENTRIES]; /* auxiliary page table entries */
} PAGETAB, *PPAGETAB;
/* VMA index macros */
#define mmVMA2TTBIndex(vma) (((vma) >> (SYS_PAGE_BITS + SYS_PGTBL_BITS)) & ((1 << SYS_TTB_BITS) - 1))
#define mmVMA2PGTBLIndex(vma) (((vma) >> SYS_PAGE_BITS) & ((1 << SYS_PGTBL_BITS) - 1))
#define mmIndices2VMA3(ttb, pgtbl, ofs) \
((((ttb) & ((1 << SYS_TTB_BITS) - 1)) << (SYS_PAGE_BITS + SYS_PGTBL_BITS)) | \
(((pgtbl) & ((1 << SYS_PGTBL_BITS) - 1)) << SYS_PAGE_BITS) | ((ofs) & (SYS_PAGE_SIZE - 1)))
/*
* Data structures for the Master Page Database.
*/
/* internal structure of a MPDB entry */
typedef struct tagMPDB1 {
PHYSADDR paPTE; /* PA of page table entry for the page */
unsigned next : 20; /* index of "next" entry in list */
unsigned tag : 12; /* page tag */
} MPDB1;
/* The MPDB entry itself. */
typedef union tagMPDB {
UINT64 raw; /* raw data */
MPDB1 d; /* structured data */
} MPDB, *PMPDB;
/* Page index macros */
#define mmPA2PageIndex(pa) ((pa) >> SYS_PAGE_BITS)
#define mmPageIndex2PA(ndx) ((ndx) << SYS_PAGE_BITS)
#endif /* __ASM__ */
#endif /* __COMROGUE_INTERNALS__ */
#endif /* __MMU_H_INCLUDED */