freebsd-skq/sys/mips/include/pte.h
jchandra 564c9a855e Support for 64 bit PTEs on n32 and n64 compilation.
In n32 and n64, add support for physical address above 4GB by having
64 bit page table entries and physical addresses. Major changes are:
- param.h: update PTE sizes, masks and shift values to support 64 bit PTEs.
- param.h: remove DELAY(), mips_btop(same as atop), mips_ptob (same as
  ptoa), and reformat.
- param.h: remove casting to unsigned long in trunc_page and round_page
  since this will be used on physical addresses.
- _types.h: have 64 bit __vm_paddr_t for n32.
- pte.h: update TLB LO0/1 access macros to support 64 bit PTE
- pte.h: assembly macros for PTE operations.
- proc.h: md_upte is now 64 bit for n32 and n64.
- exception.S and swtch.S: use the new PTE macros for PTE operations.
- cpufunc.h: TLB_LO0/1 registers are 64bit for n32 and n64.
- xlr_machdep.c: Add memory segments above 4GB to phys_avail[] as they are
  supported now.

Reviewed by:	jmallett (earlier version)
2011-01-13 15:17:29 +00:00

176 lines
6.4 KiB
C

/*-
* 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)
/*
* PFN for EntryLo register. Upper bits are 0, which is to say that
* bit 29 is the last hardware bit; Bits 30 and upwards (EntryLo is
* 64 bit though it can be referred to in 32-bits providing 2 software
* bits safely. We use it as 64 bits to get many software bits, and
* god knows what else.) are unacknowledged by hardware. They may be
* written as anything, but otherwise they have as much meaning as
* other 0 fields.
*/
#if defined(__mips_n64) || defined(__mips_n32) /* PHYSADDR_64_BIT */
#define TLBLO_SWBITS_SHIFT (34)
#define TLBLO_PFN_MASK 0x3FFFFFFC0ULL
#else
#define TLBLO_SWBITS_SHIFT (30)
#define TLBLO_PFN_MASK (0x3FFFFFC0)
#endif
#define TLBLO_PFN_SHIFT (6)
#define TLBLO_SWBITS_MASK ((pt_entry_t)0x3 << 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. ???
*/
#define PTE_RO ((pt_entry_t)0x01 << TLBLO_SWBITS_SHIFT)
#define PTE_W ((pt_entry_t)0x02 << 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) sll r, 2; srl r, 2 /* remove 2 high bits */
#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_ */