1 /*        $NetBSD: pte.h,v 1.33 2022/05/29 10:47:39 andvar Exp $ */
2 
3 /*
4  * Copyright (c) 1996
5  *        The President and Fellows of Harvard College. 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 #ifndef   _SPARC_PTE_H_
52 #define _SPARC_PTE_H_
53 
54 #if defined(_KERNEL_OPT)
55 #include "opt_sparc_arch.h"
56 #endif
57 
58 /*
59  * Sun-4 (sort of), 4c (SparcStation), and 4m Page Table Entries
60  * (Sun calls them `Page Map Entries').
61  */
62 
63 #ifndef _LOCORE
64 /*
65  * Segment maps contain `pmeg' (Page Map Entry Group) numbers.
66  * A PMEG is simply an index that names a group of 32 (sun4) or
67  * 64 (sun4c) PTEs.
68  * Depending on the CPU model, we need 7 (sun4c) to 10 (sun4/400) bits
69  * to hold the hardware MMU resource number.
70  */
71 typedef u_short pmeg_t;                 /* 10 bits needed per Sun-4 segmap entry */
72 /*
73  * Region maps contain `smeg' (Segment Entry Group) numbers.
74  * An SMEG is simply an index that names a group of 64 PMEGs.
75  */
76 typedef u_char smeg_t;                  /* 8 bits needed per Sun-4 regmap entry */
77 #endif
78 
79 /*
80  * Address translation works as follows:
81  *
82  * (for sun4c and 2-level sun4)
83  *        1. test va<31:29> -- these must be 000 or 111 (or you get a fault)
84  *        2. concatenate context_reg<2:0> and va<29:18> to get a 15 bit number;
85  *           use this to index the segment maps, yielding a 7 or 9 bit value.
86  * (for 3-level sun4)
87  *        1. concatenate context_reg<3:0> and va<31:24> to get a 8 bit number;
88  *           use this to index the region maps, yielding a 10 bit value.
89  *        2. take the value from (1) above and concatenate va<17:12> to
90  *           get a `segment map entry' index.  This gives a 9 bit value.
91  * (for sun4c)
92  *        3. take the value from (2) above and concatenate va<17:12> to
93  *           get a `page map entry' index.  This gives a 32-bit PTE.
94  * (for sun4)
95  *        3. take the value from (2 or 3) above and concatenate va<17:13> to
96  *           get a `page map entry' index.  This gives a 32-bit PTE.
97  **
98  * For sun4m:
99  *        1. Use context_reg<3:0> to index the context table (located at
100  *           (context_reg << 2) | ((ctx_tbl_ptr_reg >> 2) << 6) ). This
101  *           gives a 32-bit page-table-descriptor (PTP).
102  *        2. Use va<31:24> to index the region table located by the PTP from (1):
103  *           PTP<31:6> << 10. This gives another PTP for the segment tables
104  *        3. Use va<23:18> to index the segment table located by the PTP from (2)
105  *           as follows: PTP<31:4> << 8. This gives another PTP for the page tbl.
106  *        4. Use va<17:12> to index the page table given by (3)'s PTP:
107  *           PTP<31:4> << 8. This gives a 32-bit PTE.
108  *
109  * In other words:
110  *
111  *        struct sun4_3_levelmmu_virtual_addr {
112  *                  u_int     va_reg:8, (virtual region)
113  *                            va_seg:6, (virtual segment)
114  *                            va_pg:5,  (virtual page within segment)
115  *                            va_off:13;          (offset within page)
116  *        };
117  *        struct sun4_virtual_addr {
118  *                  u_int     :2,                 (required to be the same as bit 29)
119  *                            va_seg:12,          (virtual segment)
120  *                            va_pg:5,  (virtual page within segment)
121  *                            va_off:13;          (offset within page)
122  *        };
123  *        struct sun4c_virtual_addr {
124  *                  u_int     :2,                 (required to be the same as bit 29)
125  *                            va_seg:12,          (virtual segment)
126  *                            va_pg:6,  (virtual page within segment)
127  *                            va_off:12;          (offset within page)
128  *        };
129  *
130  *        struct sun4m_virtual_addr {
131  *                  u_int     va_reg:8, (virtual region)
132  *                            va_seg:6, (virtual segment within region)
133  *                            va_pg:6,  (virtual page within segment)
134  *                            va_off:12;          (offset within page)
135  *        };
136  *
137  * Then, given any `va':
138  *
139  *        extern smeg_t regmap[16][1<<8];                   (3-level MMU only)
140  *        extern pmeg_t segmap[8][1<<12];                   ([16][1<<12] for sun4)
141  *        extern int ptetable[128][1<<6];                   ([512][1<<5] for sun4)
142  *
143  *        extern u_int  s4m_ctxmap[16];           (sun4m SRMMU only)
144  *        extern u_int  s4m_regmap[16][1<<8];     (sun4m SRMMU only)
145  *        extern u_int  s4m_segmap[1<<8][1<<6];   (sun4m SRMMU only)
146  *        extern u_int  s4m_pagmap[1<<14][1<<6];  (sun4m SRMMU only)
147  *
148  * (the above being in the hardware, accessed as Alternate Address Spaces on
149  *  all machines but the Sun4m SRMMU, in which case the tables are in physical
150  *  kernel memory. In the 4m architecture, the tables are not laid out as
151  *  2-dim arrays, but are sparsely allocated as needed, and point to each
152  *  other.)
153  *
154  *        if (cputyp==CPU_SUN4M || cputyp==CPU_SUN4D) // SPARC Reference MMU
155  *                  regptp = s4m_ctxmap[curr_ctx];
156  *                  if (!(regptp & SRMMU_TEPTD)) TRAP();
157  *                  segptp = *(u_int *)(((regptp & ~0x3) << 4) | va.va_reg);
158  *                  if (!(segptp & SRMMU_TEPTD)) TRAP();
159  *                  pagptp = *(u_int *)(((segptp & ~0x3) << 4) | va.va_seg);
160  *                  if (!(pagptp & SRMMU_TEPTD)) TRAP();
161  *                  pte = *(u_int *)(((pagptp & ~0x3) << 4) | va.va_pg);
162  *                  if (!(pte & SRMMU_TEPTE)) TRAP();       // like PG_V
163  *                  if (usermode && PTE_PROT_LEVEL(pte) > 0x5) TRAP();
164  *                  if (writing && !PTE_PROT_LEVEL_ALLOWS_WRITING(pte)) TRAP();
165  *                  if (!(pte & SRMMU_PG_C)) DO_NOT_USE_CACHE_FOR_THIS_ACCESS();
166  *                  pte |= SRMMU_PG_U;
167  *                  if (writing) pte |= PG_M;
168  *                  physaddr = ((pte & SRMMU_PG_PFNUM) << SRMMU_PGSHIFT)|va.va_off;
169  *                  return;
170  *        if (mmu_3l)
171  *                  physreg = regmap[curr_ctx][va.va_reg];
172  *                  physseg = segmap[physreg][va.va_seg];
173  *        else
174  *                  physseg = segmap[curr_ctx][va.va_seg];
175  *        pte = ptetable[physseg][va.va_pg];
176  *        if (!(pte & PG_V)) TRAP();
177  *        if (writing && !pte.pg_w) TRAP();
178  *        if (usermode && pte.pg_s) TRAP();
179  *        if (pte & PG_NC) DO_NOT_USE_CACHE_FOR_THIS_ACCESS();
180  *        pte |= PG_U;                                                (mark used/accessed)
181  *        if (writing) pte |= PG_M;                         (mark modified)
182  *        ptetable[physseg][va.va_pg] = pte;
183  *        physadr = ((pte & PG_PFNUM) << PGSHIFT) | va.va_off;
184  */
185 
186 #if defined(SUN4_MMU3L) && !defined(SUN4)
187 #error "configuration error"
188 #endif
189 
190 #define NBPRG       (1 << 24) /* bytes per region */
191 #define RGSHIFT     24                  /* log2(NBPRG) */
192 #define RGOFSET     (NBPRG - 1)         /* mask for region offset */
193 #define NSEGRG      (NBPRG / NBPSG)     /* segments per region */
194 
195 #define NBPSG       (1 << 18) /* bytes per segment */
196 #define SGSHIFT     18                  /* log2(NBPSG) */
197 #define SGOFSET     (NBPSG - 1)         /* mask for segment offset */
198 
199 /* number of PTEs that map one segment (not number that fit in one segment!) */
200 #if defined(SUN4) && (defined(SUN4C) || defined(SUN4M) || defined(SUN4D))
201 extern int nptesg;
202 #define NPTESG      nptesg              /* (which someone will have to initialize) */
203 #else
204 #define NPTESG      (NBPSG / NBPG)
205 #endif
206 
207 /* virtual address to virtual region number */
208 #define VA_VREG(va) (((unsigned int)(va) >> RGSHIFT) & 255)
209 
210 /* virtual address to virtual segment number */
211 #define VA_VSEG(va) (((unsigned int)(va) >> SGSHIFT) & 63)
212 
213 /* virtual address to virtual page number, for Sun-4 and Sun-4c */
214 #define VA_SUN4_VPG(va)                 (((int)(va) >> 13) & 31)
215 #define VA_SUN4C_VPG(va)      (((int)(va) >> 12) & 63)
216 #define VA_SUN4M_VPG(va)      (((int)(va) >> 12) & 63)
217 #define VA_VPG(va)  \
218           (PGSHIFT==SUN4_PGSHIFT ? VA_SUN4_VPG(va) : VA_SUN4C_VPG(va))
219 
220 /* virtual address to offset within page */
221 #define VA_SUN4_OFF(va)                 (((int)(va)) & 0x1FFF)
222 #define VA_SUN4C_OFF(va)      (((int)(va)) & 0xFFF)
223 #define VA_SUN4M_OFF(va)      (((int)(va)) & 0xFFF)
224 #define VA_OFF(va)  \
225           (PGSHIFT==SUN4_PGSHIFT ? VA_SUN4_OFF(va) : VA_SUN4C_OFF(va))
226 
227 
228 /* truncate virtual address to region base */
229 #define VA_ROUNDDOWNTOREG(va) ((int)(va) & ~RGOFSET)
230 
231 /* truncate virtual address to segment base */
232 #define VA_ROUNDDOWNTOSEG(va) ((int)(va) & ~SGOFSET)
233 
234 /* virtual segment to virtual address (must sign extend on holy MMUs!) */
235 #define VRTOVA(vr)  ((CPU_HAS_SRMMU || HASSUN4_MMU3L)       \
236           ? ((int)(vr) << RGSHIFT)                                    \
237           : (((int)(vr) << (RGSHIFT+2)) >> 2))
238 #define VSTOVA(vr,vs)         ((CPU_HAS_SRMMU || HASSUN4_MMU3L)       \
239           ? (((int)(vr) << RGSHIFT) + ((int)(vs) << SGSHIFT))         \
240           : ((((int)(vr) << (RGSHIFT+2)) >> 2) + ((int)(vs) << SGSHIFT)))
241 
242 extern int mmu_has_hole;
243 #define VA_INHOLE(va)         (mmu_has_hole \
244           ? ( (unsigned int)(((int)(va) >> PG_VSHIFT) + 1) > 1) \
245           : 0)
246 
247 /* Define the virtual address space hole */
248 #define MMU_HOLE_START        0x20000000
249 #define MMU_HOLE_END          0xe0000000
250 
251 /* there is no `struct pte'; we just use `int'; this is for non-4M only */
252 #define PG_V                  0x80000000
253 #define PG_PROT               0x60000000          /* both protection bits */
254 #define PG_W                  0x40000000          /* allowed to write */
255 #define PG_S                  0x20000000          /* supervisor only */
256 #define PG_NC                 0x10000000          /* non-cacheable */
257 #define PG_TYPE               0x0c000000          /* both type bits */
258 
259 #define PG_OBMEM    0x00000000          /* on board memory */
260 #define PG_OBIO               0x04000000          /* on board I/O (incl. Sbus on 4c) */
261 #define PG_VME16    0x08000000          /* 16-bit-data VME space */
262 #define PG_VME32    0x0c000000          /* 32-bit-data VME space */
263 #if defined(SUN4M) || defined(SUN4D)
264 #define PG_SUN4M_OBMEM        0x0                 /* No type bits=>obmem on 4m */
265 #define PG_SUN4M_OBIO         0xf                 /* obio maps to 0xf on 4M */
266 #define SRMMU_PGTYPE          0xf0000000          /* Top 4 bits of pte PPN give type */
267 #endif
268 
269 #define PG_U                  0x02000000
270 #define PG_M                  0x01000000
271 #define PG_MBZ                0x00780000          /* unused; must be zero (oh really?) */
272 #define PG_IOC                0x00800000          /* IO cache, not used yet */
273 #define PG_WIRED    0x00400000          /* S/W only; in MBZ area */
274 #define PG_PFNUM    0x0007ffff          /* n.b.: only 16 bits on sun4c */
275 
276 #define PG_TNC_SHIFT          26                  /* shift to get PG_TYPE + PG_NC */
277 #define PG_M_SHIFT  24                  /* shift to get PG_M, PG_U */
278 #define PG_M_SHIFT4M          5                   /* shift to get SRMMU_PG_M,R on 4m */
279 /*efine   PG_NOACC  0                   ** XXX */
280 #define PG_KR                 0x20000000
281 #define PG_KW                 0x60000000
282 #define PG_URKR               0
283 #define PG_UW                 0x40000000
284 
285 #ifdef KGDB
286 /* but we will define one for gdb anyway */
287 struct pte {
288           u_int     pg_v:1,
289                     pg_w:1,
290                     pg_s:1,
291                     pg_nc:1;
292           enum pgtype { pg_obmem, pg_obio, pg_vme16, pg_vme32 } pg_type:2;
293           u_int     pg_u:1,
294                     pg_m:1,
295                     pg_mbz:5,
296                     pg_pfnum:19;
297 };
298 #if defined(SUN4M) || defined(SUN4D)
299 struct srmmu_pte {
300           u_int     pg_pfnum:24,
301                     pg_c:1,
302                     pg_m:1,
303                     pg_u:1;
304           enum pgprot { pprot_r_r, pprot_rw_rw, pprot_rx_rx, pprot_rwx_rwx,
305                           pprot_x_x, pprot_r_rw, pprot_n_rx, pprot_n_rwx }
306                     pg_prot:3;          /* prot. bits: pprot_<user>_<supervisor> */
307           u_int     pg_must_be_2:2;
308 };
309 #endif
310 #endif
311 
312 /*
313  * These are needed in the register window code
314  * to check the validity of (ostensible) user stack PTEs.
315  */
316 #define PG_VSHIFT   29                  /* (va>>vshift)==0 or -1 => valid */
317           /* XXX fix this name, it is a va shift not a pte bit shift! */
318 
319 #define PG_PROTSHIFT          29
320 #define PG_PROTUWRITE         6                   /* PG_V,PG_W,!PG_S */
321 #define PG_PROTUREAD          4                   /* PG_V,!PG_W,!PG_S */
322 
323 /* %%%: Fix above and below for 4m? */
324 
325 /* static __inline int PG_VALID(void *va) {
326           register int t = va; t >>= PG_VSHIFT; return (t == 0 || t == -1);
327 } */
328 
329 
330 /*
331  * Here are the bit definitions for 4M/SRMMU pte's
332  */
333                     /* MMU TABLE ENTRIES */
334 #define SRMMU_TEINVALID       0x0                 /* invalid (serves as !valid bit) */
335 #define SRMMU_TEPTD 0x1                 /* Page Table Descriptor */
336 #define SRMMU_TEPTE 0x2                 /* Page Table Entry */
337 #define SRMMU_TEPTERBO        0x3                 /* Page Table Entry with Reverse Byte
338                                                      Order (SS-II) */
339 #define SRMMU_TETYPE          0x3                 /* mask for table entry type */
340                     /* PTE FIELDS */
341 #define SRMMU_PPNMASK         0xFFFFFF00
342 #define SRMMU_PPNSHIFT        0x8
343 #define SRMMU_PPNPASHIFT 0x4            /* shift to put ppn into PAddr */
344 #define SRMMU_L1PPNSHFT       0x14
345 #define SRMMU_L1PPNMASK       0xFFF00000
346 #define SRMMU_L2PPNSHFT 0xE
347 #define SRMMU_L2PPNMASK       0xFC000
348 #define SRMMU_L3PPNSHFT       0x8
349 #define SRMMU_L3PPNMASK 0x3F00
350                     /* PTE BITS */
351 #define SRMMU_PG_C  0x80                /* cacheable */
352 #define SRMMU_PG_M  0x40                /* modified (dirty) */
353 #define SRMMU_PG_R  0x20                /* referenced */
354 #define SRMMU_PGBITSMSK       0xE0
355                     /* PTE PROTECTION */
356 #define SRMMU_PROT_MASK       0x1C                /* Mask protection bits out of pte */
357 #define SRMMU_PROT_SHFT       0x2
358 #define PPROT_R_R   0x0                 /* These are in the form:     */
359 #define PPROT_RW_RW 0x4                 /*        PPROT_<u>_<s>                 */
360 #define PPROT_RX_RX 0x8                 /* where <u> is the user-mode */
361 #define PPROT_RWX_RWX         0xC                 /* permission, and <s> is the           */
362 #define PPROT_X_X   0x10                /* supervisor mode permission.          */
363 #define PPROT_R_RW  0x14                /* R=read, W=write, X=execute */
364 #define PPROT_N_RX  0x18                /* N=none.                              */
365 #define PPROT_N_RWX 0x1C
366 #define PPROT_WRITE 0x4                 /* set iff write priv. allowed  */
367 #define PPROT_S               0x18                /* effective S bit */
368 #define PPROT_U2S_OMASK 0x18            /* OR with prot. to revoke user priv */
369                     /* TABLE SIZES */
370 #define SRMMU_L1SIZE          0x100
371 #define SRMMU_L2SIZE          0x40
372 #define SRMMU_L3SIZE          0x40
373 
374 #define SRMMU_PTE_BITS        "\177\020"                                                  \
375           "f\0\2TYPE\0=\1PTD\0=\2PTE\0f\2\3PROT\0"                              \
376           "=\0R_R\0=\4RW_RW\0=\10RX_RX\0=\14RWX_RWX\0=\20X_X\0=\24R_RW\0"       \
377           "=\30N_RX\0=\34N_RWX\0"                                                         \
378           "b\5R\0b\6M\0b\7C\0f\10\30PFN\0"
379 
380 /*
381  * IOMMU PTE bits.
382  */
383 #define IOPTE_PPN_MASK  0x07ffff00
384 #define IOPTE_PPN_SHIFT 8
385 #define IOPTE_RSVD      0x000000f1
386 #define IOPTE_WRITE     0x00000004
387 #define IOPTE_VALID     0x00000002
388 
389 #define IOMMU_PTE_BITS        "\177\020"                                                  \
390           "f\10\23PPN\0b\2W\0b\1V\0"
391 
392 
393 #if defined(_KERNEL) || defined(_STANDALONE)
394 /*
395  * Macros to get and set the processor context.
396  */
397 #define getcontext4()                   lduba(AC_CONTEXT, ASI_CONTROL)
398 #define getcontext4m()                  lda(SRMMU_CXR, ASI_SRMMU)
399 #define getcontext()                    (CPU_HAS_SRMMU ? getcontext4m()                   \
400                                                          : getcontext4())
401 
402 #define setcontext4(c)                  stba(AC_CONTEXT, ASI_CONTROL, c)
403 #define setcontext4m(c)                 sta(SRMMU_CXR, ASI_SRMMU, c)
404 #define setcontext(c)                   (CPU_HAS_SRMMU ? setcontext4m(c)        \
405                                                          : setcontext4(c))
406 
407 /* sun4/sun4c access to MMU-resident PTEs */
408 #define getpte4(va)           lda(va, ASI_PTE)
409 #define setpte4(va, pte)      sta(va, ASI_PTE, pte)
410 
411 /* sun4m TLB probe */
412 #define getpte4m(va)                    lda((va & 0xFFFFF000) | ASI_SRMMUFP_L3, \
413                                             ASI_SRMMUFP)
414 
415 #endif /* _KERNEL || _STANDALONE */
416 #endif /* _SPARC_PTE_H_ */
417