pte.h revision 1.16
1/*	$NetBSD: pte.h,v 1.16 1996/05/15 02:13:50 mrg Exp $ */
2
3/*
4 * Copyright (c) 1996
5 * 	The President and Fellows of Harvard University. All rights reserved.
6 * Copyright (c) 1992, 1993
7 *	The Regents of the University of California.  All rights reserved.
8 *
9 * This software was developed by the Computer Systems Engineering group
10 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
11 * contributed to Berkeley.
12 *
13 * All advertising materials mentioning features or use of this software
14 * must display the following acknowledgements:
15 * 	This product includes software developed by Harvard University.
16 *	This product includes software developed by the University of
17 *	California, Lawrence Berkeley Laboratory.
18 *
19 * Redistribution and use in source and binary forms, with or without
20 * modification, are permitted provided that the following conditions
21 * are met:
22 * 1. Redistributions of source code must retain the above copyright
23 *    notice, this list of conditions and the following disclaimer.
24 * 2. Redistributions in binary form must reproduce the above copyright
25 *    notice, this list of conditions and the following disclaimer in the
26 *    documentation and/or other materials provided with the distribution.
27 * 3. All advertising materials mentioning features or use of this software
28 *    must display the following acknowledgements:
29 *	This product includes software developed by Harvard University.
30 *	This product includes software developed by the University of
31 *	California, Berkeley and its contributors.
32 * 4. Neither the name of the University nor the names of its contributors
33 *    may be used to endorse or promote products derived from this software
34 *    without specific prior written permission.
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
37 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
40 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46 * SUCH DAMAGE.
47 *
48 *	@(#)pte.h	8.1 (Berkeley) 6/11/93
49 */
50
51/*
52 * Sun-4 (sort of), 4c (SparcStation), and 4m Page Table Entries
53 * (Sun calls them `Page Map Entries').
54 */
55
56#ifndef _LOCORE
57/*
58 * Segment maps contain `pmeg' (Page Map Entry Group) numbers.
59 * A PMEG is simply an index that names a group of 32 (sun4) or
60 * 64 (sun4c) PTEs.
61 * Depending on the CPU model, we need 7 (sun4c) to 10 (sun4/400) bits
62 * to hold the hardware MMU resource number.
63 */
64typedef u_short pmeg_t;		/* 10 bits needed per Sun-4 segmap entry */
65/*
66 * Region maps contain `smeg' (Segment Entry Group) numbers.
67 * An SMEG is simply an index that names a group of 64 PMEGs.
68 */
69typedef u_char smeg_t;		/* 8 bits needed per Sun-4 regmap entry */
70#endif
71
72/*
73 * Address translation works as follows:
74 *
75 * (for sun4c and 2-level sun4)
76 *	1. test va<31:29> -- these must be 000 or 111 (or you get a fault)
77 *	2. concatenate context_reg<2:0> and va<29:18> to get a 15 bit number;
78 *	   use this to index the segment maps, yielding a 7 or 9 bit value.
79 * (for 3-level sun4)
80 *	1. concatenate context_reg<3:0> and va<31:24> to get a 8 bit number;
81 *	   use this to index the region maps, yielding a 10 bit value.
82 *	2. take the value from (1) above and concatenate va<17:12> to
83 *	   get a `segment map entry' index.  This gives a 9 bit value.
84 * (for sun4c)
85 *	3. take the value from (2) above and concatenate va<17:12> to
86 *	   get a `page map entry' index.  This gives a 32-bit PTE.
87 * (for sun4)
88 *	3. take the value from (2 or 3) above and concatenate va<17:13> to
89 *	   get a `page map entry' index.  This gives a 32-bit PTE.
90 **
91 * For sun4m:
92 *	1. Use context_reg<3:0> to index the context table (located at
93 *	   (context_reg << 2) | ((ctx_tbl_ptr_reg >> 2) << 6) ). This
94 *	   gives a 32-bit page-table-descriptor (PTP).
95 *	2. Use va<31:24> to index the region table located by the PTP from (1):
96 *	   PTP<31:6> << 10. This gives another PTP for the segment tables
97 *	3. Use va<23:18> to index the segment table located by the PTP from (2)
98 *	   as follows: PTP<31:4> << 8. This gives another PTP for the page tbl.
99 * 	4. Use va<17:12> to index the page table given by (3)'s PTP:
100 * 	   PTP<31:4> << 8. This gives a 32-bit PTE.
101 *
102 * In other words:
103 *
104 *	struct sun4_3_levelmmu_virtual_addr {
105 *		u_int	va_reg:8,	(virtual region)
106 *			va_seg:6,	(virtual segment)
107 *			va_pg:5,	(virtual page within segment)
108 *			va_off:13;	(offset within page)
109 *	};
110 *	struct sun4_virtual_addr {
111 *		u_int	:2,		(required to be the same as bit 29)
112 *			va_seg:12,	(virtual segment)
113 *			va_pg:5,	(virtual page within segment)
114 *			va_off:13;	(offset within page)
115 *	};
116 *	struct sun4c_virtual_addr {
117 *		u_int	:2,		(required to be the same as bit 29)
118 *			va_seg:12,	(virtual segment)
119 *			va_pg:6,	(virtual page within segment)
120 *			va_off:12;	(offset within page)
121 *	};
122 *
123 *	struct sun4m_virtual_addr {
124 *		u_int	va_reg:8,	(virtual region)
125 *			va_seg:6,	(virtual segment within region)
126 *			va_pg:6,	(virtual page within segment)
127 *			va_off:12;	(offset within page)
128 *	};
129 *
130 * Then, given any `va':
131 *
132 *	extern smeg_t regmap[16][1<<8];		(3-level MMU only)
133 *	extern pmeg_t segmap[8][1<<12];		([16][1<<12] for sun4)
134 *	extern int ptetable[128][1<<6];		([512][1<<5] for sun4)
135 *
136 *	extern u_int  s4m_ctxmap[16];		(sun4m SRMMU only)
137 *	extern u_int  s4m_regmap[16][1<<8];	(sun4m SRMMU only)
138 * 	extern u_int  s4m_segmap[1<<8][1<<6];	(sun4m SRMMU only)
139 * 	extern u_int  s4m_pagmap[1<<14][1<<6];	(sun4m SRMMU only)
140 *
141 * (the above being in the hardware, accessed as Alternate Address Spaces on
142 *  all machines but the Sun4m SRMMU, in which case the tables are in physical
143 *  kernel memory. In the 4m architecture, the tables are not layed out as
144 *  2-dim arrays, but are sparsely allocated as needed, and point to each
145 *  other.)
146 *
147 *	if (cputyp==CPU_SUN4M) 		// SPARC Reference MMU
148 *		regptp = s4m_ctxmap[curr_ctx];
149 *		if (!(regptp & SRMMU_TEPTD)) TRAP();
150 *		segptp = *(u_int *)(((regptp & ~0x3) << 4) | va.va_reg);
151 *		if (!(segptp & SRMMU_TEPTD)) TRAP();
152 *		pagptp = *(u_int *)(((segptp & ~0x3) << 4) | va.va_seg);
153 *		if (!(pagptp & SRMMU_TEPTD)) TRAP();
154 *		pte = *(u_int *)(((pagptp & ~0x3) << 4) | va.va_pg);
155 *		if (!(pte & SRMMU_TEPTE)) TRAP();       // like PG_V
156 * 		if (usermode && PTE_PROT_LEVEL(pte) > 0x5) TRAP();
157 *		if (writing && !PTE_PROT_LEVEL_ALLOWS_WRITING(pte)) TRAP();
158 *		if (!(pte & SRMMU_PG_C)) DO_NOT_USE_CACHE_FOR_THIS_ACCESS();
159 *		pte |= SRMMU_PG_U;
160 * 		if (writing) pte |= PG_M;
161 * 		physaddr = ((pte & SRMMU_PG_PFNUM) << SRMMU_PGSHIFT)|va.va_off;
162 *		return;
163 *	if (mmu_3l)
164 *		physreg = regmap[curr_ctx][va.va_reg];
165 *		physseg = segmap[physreg][va.va_seg];
166 *	else
167 *		physseg = segmap[curr_ctx][va.va_seg];
168 *	pte = ptetable[physseg][va.va_pg];
169 *	if (!(pte & PG_V)) TRAP();
170 *	if (writing && !pte.pg_w) TRAP();
171 *	if (usermode && pte.pg_s) TRAP();
172 *	if (pte & PG_NC) DO_NOT_USE_CACHE_FOR_THIS_ACCESS();
173 *	pte |= PG_U;					(mark used/accessed)
174 *	if (writing) pte |= PG_M;			(mark modified)
175 *	ptetable[physseg][va.va_pg] = pte;
176 *	physadr = ((pte & PG_PFNUM) << PGSHIFT) | va.va_off;
177 */
178
179#if defined(MMU_3L) && !defined(SUN4)
180#error "configuration error"
181#endif
182
183#if defined(MMU_3L)
184extern int mmu_3l;
185#endif
186
187#define	NBPRG	(1 << 24)	/* bytes per region */
188#define	RGSHIFT	24		/* log2(NBPRG) */
189#define	RGOFSET	(NBPRG - 1)	/* mask for region offset */
190#define NSEGRG	(NBPRG / NBPSG)	/* segments per region */
191
192#define	NBPSG	(1 << 18)	/* bytes per segment */
193#define	SGSHIFT	18		/* log2(NBPSG) */
194#define	SGOFSET	(NBPSG - 1)	/* mask for segment offset */
195
196/* number of PTEs that map one segment (not number that fit in one segment!) */
197#if defined(SUN4) && (defined(SUN4C) || defined(SUN4M))
198extern int nptesg;
199#define	NPTESG	nptesg		/* (which someone will have to initialize) */
200#else
201#define	NPTESG	(NBPSG / NBPG)
202#endif
203
204/* virtual address to virtual region number */
205#define	VA_VREG(va)	(((unsigned int)(va) >> RGSHIFT) & 255)
206
207/* virtual address to virtual segment number */
208#define	VA_VSEG(va)	(((unsigned int)(va) >> SGSHIFT) & 63)
209
210/* virtual address to virtual page number, for Sun-4 and Sun-4c */
211#define	VA_SUN4_VPG(va)		(((int)(va) >> 13) & 31)
212#define	VA_SUN4C_VPG(va)	(((int)(va) >> 12) & 63)
213#define VA_SUN4M_VPG(va)	(((int)(va) >> 12) & 63)
214
215/* virtual address to offset within page */
216#define VA_SUN4_OFF(va)       	(((int)(va)) & 0x1FFF)
217#define VA_SUN4C_OFF(va)     	(((int)(va)) & 0xFFF)
218#define VA_SUN4M_OFF(va)	(((int)(va)) & 0xFFF)
219
220/* truncate virtual address to region base */
221#define	VA_ROUNDDOWNTOREG(va)	((int)(va) & ~RGOFSET)
222
223/* truncate virtual address to segment base */
224#define	VA_ROUNDDOWNTOSEG(va)	((int)(va) & ~SGOFSET)
225
226/* virtual segment to virtual address (must sign extend on holy MMUs!) */
227#if defined(SUN4M) && !(defined(SUN4C) || defined(SUN4))
228#define VRTOVA(vr)	((int)(vr) << RGSHIFT)
229#define VSTOVA(vr,vs)	(((int)(vr) << RGSHIFT) + ((int)(vs) << SGSHIFT))
230#else
231#if defined(MMU_3L) || defined(SUN4M)	/* hairy.. */
232#if !defined(MMU_3L)
233#define _PTE_HAIRY_3L_TEST	(cputyp==CPU_SUN4M)
234#elif !defined(SUN4M)
235#define _PTE_HAIRY_3L_TEST	(mmu_3l)
236#else
237#define _PTE_HAIRY_3L_TEST	(mmu_3l || cputyp==CPU_SUN4M)
238#endif
239#define	VRTOVA(vr)	(_PTE_HAIRY_3L_TEST	\
240	? ((int)(vr) << RGSHIFT)		\
241	: (((int)(vr) << (RGSHIFT+2)) >> 2))
242#define	VSTOVA(vr,vs)	(_PTE_HAIRY_3L_TEST	\
243	? (((int)(vr) << RGSHIFT) + ((int)(vs) << SGSHIFT))	\
244	: ((((int)(vr) << (RGSHIFT+2)) >> 2) + ((int)(vs) << SGSHIFT)))
245#else
246#define	VRTOVA(vr)	(((int)(vr) << (RGSHIFT+2)) >> 2)
247#define	VSTOVA(vr,vs)	((((int)(vr) << (RGSHIFT+2)) >> 2) + \
248			 ((int)(vs) << SGSHIFT))
249#endif
250#endif
251
252extern int mmu_has_hole;
253#define VA_INHOLE(va)	(mmu_has_hole \
254	? ( (unsigned int)(((int)(va) >> PG_VSHIFT) + 1) > 1) \
255	: 0)
256
257/* Define the virtual address space hole */
258#define MMU_HOLE_START	0x20000000
259#define MMU_HOLE_END	0xe0000000
260
261#if defined(SUN4M)		/* Optimization: sun4m, sun4c have same page */
262#if defined(SUN4)		/* size, so they're used interchangeably */
263#define VA_VPG(va)	(cputyp==CPU_SUN4 ? VA_SUN4_VPG(va) : VA_SUN4C_VPG(va))
264#define VA_OFF(VA)	(cputyp==CPU_SUN4 ? VA_SUN4_OFF(va) : VA_SUN4C_OFF(va))
265#else
266#define VA_VPG(va)	VA_SUN4M_VPG(va)
267#define VA_OFF(va)	VA_SUN4M_OFF(va)
268#endif /* defined SUN4 */
269#else /* 4m not defined */
270#if defined(SUN4) && defined(SUN4C)
271#define VA_VPG(va)	(cputyp==CPU_SUN4C ? VA_SUN4C_VPG(va) : VA_SUN4_VPG(va))
272#define VA_OFF(va)	(cputyp==CPU_SUN4C ? VA_SUN4C_OFF(va) : VA_SUN4_OFF(va))
273#endif
274#if defined(SUN4C) && !defined(SUN4)
275#define VA_VPG(va)	VA_SUN4C_VPG(va)
276#define VA_OFF(va)	VA_SUN4C_OFF(va)
277#endif
278#if !defined(SUN4C) && defined(SUN4)
279#define	VA_VPG(va)	VA_SUN4_VPG(va)
280#define VA_OFF(va)	VA_SUN4_OFF(va)
281#endif
282#endif /* defined 4m */
283
284/* there is no `struct pte'; we just use `int'; this is for non-4M only */
285#define	PG_V		0x80000000
286#define	PG_PROT		0x60000000	/* both protection bits */
287#define	PG_W		0x40000000	/* allowed to write */
288#define	PG_S		0x20000000	/* supervisor only */
289#define	PG_NC		0x10000000	/* non-cacheable */
290#define	PG_TYPE		0x0c000000	/* both type bits */
291
292#define	PG_OBMEM	0x00000000	/* on board memory */
293#define	PG_OBIO		0x04000000	/* on board I/O (incl. Sbus on 4c) */
294#define	PG_VME16	0x08000000	/* 16-bit-data VME space */
295#define	PG_VME32	0x0c000000	/* 32-bit-data VME space */
296#if defined(SUN4M)
297#define PG_SUN4M_OBMEM	0x0	       	/* No type bits=>obmem on 4m */
298#define PG_SUN4M_OBIO	0xf		/* obio maps to 0xf on 4M */
299#define SRMMU_PGTYPE	0xf0000000	/* Top 4 bits of pte PPN give type */
300#endif
301
302#define	PG_U		0x02000000
303#define	PG_M		0x01000000
304#define PG_IOC		0x00800000
305#define	PG_MBZ		0x00780000	/* unused; must be zero (oh really?) */
306#define	PG_PFNUM	0x0007ffff	/* n.b.: only 16 bits on sun4c */
307
308#define	PG_TNC_SHIFT	26		/* shift to get PG_TYPE + PG_NC */
309#define	PG_M_SHIFT	24		/* shift to get PG_M, PG_U */
310#define PG_M_SHIFT4M	5		/* shift to get SRMMU_PG_M,R on 4m */
311/*efine	PG_NOACC	0		** XXX */
312#define	PG_KR		0x20000000
313#define	PG_KW		0x60000000
314#define	PG_URKR		0
315#define	PG_UW		0x40000000
316
317#ifdef KGDB
318/* but we will define one for gdb anyway */
319struct pte {
320	u_int	pg_v:1,
321		pg_w:1,
322		pg_s:1,
323		pg_nc:1;
324	enum pgtype { pg_obmem, pg_obio, pg_vme16, pg_vme32 } pg_type:2;
325	u_int	pg_u:1,
326		pg_m:1,
327		pg_mbz:5,
328		pg_pfnum:19;
329};
330#if defined(SUN4M)
331struct srmmu_pte {
332	u_int	pg_pfnum:20,
333		pg_c:1,
334		pg_m:1,
335		pg_u:1;
336	enum pgprot { pprot_r_r, pprot_rw_rw, pprot_rx_rx, pprot_rwx_rwx,
337		      pprot_x_x, pprot_r_rw, pprot_n_rx, pprot_n_rwx }
338		pg_prot:3;	/* prot. bits: pprot_<user>_<supervisor> */
339	u_int	pg_must_be_2:2;
340};
341#endif
342#endif
343
344/*
345 * These are needed in the register window code
346 * to check the validity of (ostensible) user stack PTEs.
347 */
348#define	PG_VSHIFT	29		/* (va>>vshift)==0 or -1 => valid */
349	/* XXX fix this name, it is a va shift not a pte bit shift! */
350
351#define	PG_PROTSHIFT	29
352#define	PG_PROTUWRITE	6		/* PG_V,PG_W,!PG_S */
353#define	PG_PROTUREAD	4		/* PG_V,!PG_W,!PG_S */
354
355/* %%%: Fix above and below for 4m? */
356
357/* static __inline int PG_VALID(void *va) {
358	register int t = va; t >>= PG_VSHIFT; return (t == 0 || t == -1);
359} */
360
361
362/*
363 * Here are the bit definitions for 4M/SRMMU pte's
364 */
365		/* MMU TABLE ENTRIES */
366#define SRMMU_TEINVALID	0x0		/* invalid (serves as !valid bit) */
367#define	SRMMU_TEPTD	0x1		/* Page Table Descriptor */
368#define SRMMU_TEPTE	0x2		/* Page Table Entry */
369#define SRMMU_TERES	0x3		/* reserved */
370#define SRMMU_TETYPE	0x3		/* mask for table entry type */
371		/* PTE FIELDS */
372#define SRMMU_PPNMASK	0xFFFFFF00
373#define SRMMU_PPNSHIFT	0x8
374#define SRMMU_PPNPASHIFT 0x4 		/* shift to put ppn into PAddr */
375#define SRMMU_L1PPNSHFT	0x14
376#define SRMMU_L1PPNMASK	0xFFF00000
377#define SRMMU_L2PPNSHFT 0xE
378#define SRMMU_L2PPNMASK	0xFC000
379#define SRMMU_L3PPNSHFT	0x8
380#define SRMMU_L3PPNMASK 0x3F00
381		/* PTE BITS */
382#define SRMMU_PG_C	0x80		/* cacheable */
383#define SRMMU_PG_M	0x40		/* modified (dirty) */
384#define SRMMU_PG_R	0x20		/* referenced */
385#define SRMMU_PGBITSMSK	0xE0
386		/* PTE PROTECTION */
387#define SRMMU_PROT_MASK	0x1C		/* Mask protection bits out of pte */
388#define SRMMU_PROT_SHFT	0x2
389#define PPROT_R_R	0x0		/* These are in the form:	*/
390#define PPROT_RW_RW	0x4		/* 	PPROT_<u>_<s>		*/
391#define PPROT_RX_RX	0x8		/* where <u> is the user-mode	*/
392#define PPROT_RWX_RWX	0xC		/* permission, and <s> is the 	*/
393#define PPROT_X_X	0x10		/* supervisor mode permission.	*/
394#define PPROT_R_RW	0x14		/* R=read, W=write, X=execute	*/
395#define PPROT_N_RX	0x18		/* N=none.			*/
396#define PPROT_N_RWX	0x1C
397#define PPROT_WRITE	0x4		/* set iff write priv. allowed  */
398#define PPROT_S		0x18		/* effective S bit */
399#define PPROT_U2S_OMASK 0x18		/* OR with prot. to revoke user priv */
400		/* TABLE SIZES */
401#define SRMMU_L1SIZE	0x100
402#define SRMMU_L2SIZE 	0x40
403#define SRMMU_L3SIZE	0x40
404
405/*
406 * IOMMU PTE bits.
407 */
408#define IOPTE_PPN_MASK  0x07ffff00
409#define IOPTE_PPN_SHIFT 8
410#define IOPTE_RSVD      0x000000f1
411#define IOPTE_WRITE     0x00000004
412#define IOPTE_VALID     0x00000002
413