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/*-
* Copyright (c) 2004-2010 Juli Mallett <jmallett@FreeBSD.org>
* All rights reserved.
*
* 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 AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#ifndef _MACHINE_PTE_H_
#define _MACHINE_PTE_H_
#ifndef _LOCORE
#if defined(__mips_n64) || defined(__mips_n32) /* PHYSADDR_64_BIT */
typedef uint64_t pt_entry_t;
#else
typedef uint32_t pt_entry_t;
#endif
typedef pt_entry_t *pd_entry_t;
#endif
/*
* TLB and PTE management. Most things operate within the context of
* EntryLo0,1, and begin with TLBLO_. Things which work with EntryHi
* start with TLBHI_. PTE bits begin with PTE_.
*
* Note that we use the same size VM and TLB pages.
*/
#define TLB_PAGE_SHIFT (PAGE_SHIFT)
#define TLB_PAGE_SIZE (1 << TLB_PAGE_SHIFT)
#define TLB_PAGE_MASK (TLB_PAGE_SIZE - 1)
/*
* TLB PageMask register. Has mask bits set above the default, 4K, page mask.
*/
#define TLBMASK_SHIFT (13)
#define TLBMASK_MASK ((PAGE_MASK >> TLBMASK_SHIFT) << TLBMASK_SHIFT)
/*
* FreeBSD/mips page-table entries take a near-identical format to MIPS TLB
* entries, each consisting of two 32-bit or 64-bit values ("EntryHi" and
* "EntryLo"). MIPS4k and MIPS64 both define certain bits in TLB entries as
* reserved, and these must be zero-filled by software. We overload these
* bits in PTE entries to hold PTE_ flags such as RO, W, and MANAGED.
* However, we must mask these out when writing to TLB entries to ensure that
* they do not become visible to hardware -- especially on MIPS64r2 which has
* an extended physical memory space.
*
* When using n64 and n32, shift software-defined bits into the MIPS64r2
* reserved range, which runs from bit 55 ... 63. In other configurations
* (32-bit MIPS4k and compatible), shift them out to bits 29 ... 31.
*
* NOTE: This means that for 32-bit use of CP0, we aren't able to set the top
* bit of PFN to a non-zero value, as software is using it! This physical
* memory size limit may not be sufficiently enforced elsewhere.
*/
#if defined(__mips_n64) || defined(__mips_n32) /* PHYSADDR_64_BIT */
#define TLBLO_SWBITS_SHIFT (55)
#define TLBLO_SWBITS_CLEAR_SHIFT (9)
#define TLBLO_PFN_MASK 0x3FFFFFFC0ULL
#else
#define TLBLO_SWBITS_SHIFT (29)
#define TLBLO_PFN_MASK (0x1FFFFFC0)
#endif
#define TLBLO_PFN_SHIFT (6)
#define TLBLO_SWBITS_MASK ((pt_entry_t)0x7 << TLBLO_SWBITS_SHIFT)
#define TLBLO_PA_TO_PFN(pa) ((((pa) >> TLB_PAGE_SHIFT) << TLBLO_PFN_SHIFT) & TLBLO_PFN_MASK)
#define TLBLO_PFN_TO_PA(pfn) ((vm_paddr_t)((pfn) >> TLBLO_PFN_SHIFT) << TLB_PAGE_SHIFT)
#define TLBLO_PTE_TO_PFN(pte) ((pte) & TLBLO_PFN_MASK)
#define TLBLO_PTE_TO_PA(pte) (TLBLO_PFN_TO_PA(TLBLO_PTE_TO_PFN((pte))))
/*
* XXX This comment is not correct for anything more modern than R4K.
*
* VPN for EntryHi register. Upper two bits select user, supervisor,
* or kernel. Bits 61 to 40 copy bit 63. VPN2 is bits 39 and down to
* as low as 13, down to PAGE_SHIFT, to index 2 TLB pages*. From bit 12
* to bit 8 there is a 5-bit 0 field. Low byte is ASID.
*
* XXX This comment is not correct for FreeBSD.
* Note that in FreeBSD, we map 2 TLB pages is equal to 1 VM page.
*/
#define TLBHI_ASID_MASK (0xff)
#if defined(__mips_n64)
#define TLBHI_R_SHIFT 62
#define TLBHI_R_USER (0x00UL << TLBHI_R_SHIFT)
#define TLBHI_R_SUPERVISOR (0x01UL << TLBHI_R_SHIFT)
#define TLBHI_R_KERNEL (0x03UL << TLBHI_R_SHIFT)
#define TLBHI_R_MASK (0x03UL << TLBHI_R_SHIFT)
#define TLBHI_VA_R(va) ((va) & TLBHI_R_MASK)
#define TLBHI_FILL_SHIFT 40
#define TLBHI_VPN2_SHIFT (TLB_PAGE_SHIFT + 1)
#define TLBHI_VPN2_MASK (((~((1UL << TLBHI_VPN2_SHIFT) - 1)) << (63 - TLBHI_FILL_SHIFT)) >> (63 - TLBHI_FILL_SHIFT))
#define TLBHI_VA_TO_VPN2(va) ((va) & TLBHI_VPN2_MASK)
#define TLBHI_ENTRY(va, asid) ((TLBHI_VA_R((va))) /* Region. */ | \
(TLBHI_VA_TO_VPN2((va))) /* VPN2. */ | \
((asid) & TLBHI_ASID_MASK))
#else /* !defined(__mips_n64) */
#define TLBHI_PAGE_MASK (2 * PAGE_SIZE - 1)
#define TLBHI_ENTRY(va, asid) (((va) & ~TLBHI_PAGE_MASK) | ((asid) & TLBHI_ASID_MASK))
#endif /* defined(__mips_n64) */
/*
* TLB flags managed in hardware:
* C: Cache attribute.
* D: Dirty bit. This means a page is writable. It is not
* set at first, and a write is trapped, and the dirty
* bit is set. See also PTE_RO.
* V: Valid bit. Obvious, isn't it?
* G: Global bit. This means that this mapping is present
* in EVERY address space, and to ignore the ASID when
* it is matched.
*/
#define PTE_C(attr) ((attr & 0x07) << 3)
#define PTE_C_UNCACHED (PTE_C(MIPS_CCA_UNCACHED))
#define PTE_C_CACHE (PTE_C(MIPS_CCA_CACHED))
#define PTE_D 0x04
#define PTE_V 0x02
#define PTE_G 0x01
/*
* VM flags managed in software:
* RO: Read only. Never set PTE_D on this page, and don't
* listen to requests to write to it.
* W: Wired. ???
* MANAGED:Managed. This PTE maps a managed page.
*
* These bits should not be written into the TLB, so must first be masked out
* explicitly in C, or using CLEAR_PTE_SWBITS() in assembly.
*/
#define PTE_RO ((pt_entry_t)0x01 << TLBLO_SWBITS_SHIFT)
#define PTE_W ((pt_entry_t)0x02 << TLBLO_SWBITS_SHIFT)
#define PTE_MANAGED ((pt_entry_t)0x04 << TLBLO_SWBITS_SHIFT)
/*
* PTE management functions for bits defined above.
*/
#define pte_clear(pte, bit) (*(pte) &= ~(bit))
#define pte_set(pte, bit) (*(pte) |= (bit))
#define pte_test(pte, bit) ((*(pte) & (bit)) == (bit))
/* Assembly support for PTE access*/
#ifdef LOCORE
#if defined(__mips_n64) || defined(__mips_n32) /* PHYSADDR_64_BIT */
#define PTESHIFT 3
#define PTE2MASK 0xff0 /* for the 2-page lo0/lo1 */
#define PTEMASK 0xff8
#define PTESIZE 8
#define PTE_L ld
#define PTE_MTC0 dmtc0
#define CLEAR_PTE_SWBITS(pr)
#else
#define PTESHIFT 2
#define PTE2MASK 0xff8 /* for the 2-page lo0/lo1 */
#define PTEMASK 0xffc
#define PTESIZE 4
#define PTE_L lw
#define PTE_MTC0 mtc0
#define CLEAR_PTE_SWBITS(r) LONG_SLL r, TLBLO_SWBITS_CLEAR_SHIFT; LONG_SRL r, TLBLO_SWBITS_CLEAR_SHIFT /* remove swbits */
#endif /* defined(__mips_n64) || defined(__mips_n32) */
#if defined(__mips_n64)
#define PTRSHIFT 3
#define PDEPTRMASK 0xff8
#else
#define PTRSHIFT 2
#define PDEPTRMASK 0xffc
#endif
#endif /* LOCORE */
#endif /* !_MACHINE_PTE_H_ */
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