1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * pgtsrmmu.h:  SRMMU page table defines and code.
4 *
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6 */
7
8#ifndef _SPARC_PGTSRMMU_H
9#define _SPARC_PGTSRMMU_H
10
11#include <asm/page.h>
12
13#ifdef __ASSEMBLY__
14#include <asm/thread_info.h>	/* TI_UWINMASK for WINDOW_FLUSH */
15#endif
16
17/* Number of contexts is implementation-dependent; 64k is the most we support */
18#define SRMMU_MAX_CONTEXTS	65536
19
20#define SRMMU_PTE_TABLE_SIZE		(PTRS_PER_PTE*4)
21#define SRMMU_PMD_TABLE_SIZE		(PTRS_PER_PMD*4)
22#define SRMMU_PGD_TABLE_SIZE		(PTRS_PER_PGD*4)
23
24/* Definition of the values in the ET field of PTD's and PTE's */
25#define SRMMU_ET_MASK         0x3
26#define SRMMU_ET_INVALID      0x0
27#define SRMMU_ET_PTD          0x1
28#define SRMMU_ET_PTE          0x2
29#define SRMMU_ET_REPTE        0x3 /* AIEEE, SuperSparc II reverse endian page! */
30
31/* Physical page extraction from PTP's and PTE's. */
32#define SRMMU_CTX_PMASK    0xfffffff0
33#define SRMMU_PTD_PMASK    0xfffffff0
34#define SRMMU_PTE_PMASK    0xffffff00
35
36/* The pte non-page bits.  Some notes:
37 * 1) cache, dirty, valid, and ref are frobbable
38 *    for both supervisor and user pages.
39 * 2) exec and write will only give the desired effect
40 *    on user pages
41 * 3) use priv and priv_readonly for changing the
42 *    characteristics of supervisor ptes
43 */
44#define SRMMU_CACHE        0x80
45#define SRMMU_DIRTY        0x40
46#define SRMMU_REF          0x20
47#define SRMMU_NOREAD       0x10
48#define SRMMU_EXEC         0x08
49#define SRMMU_WRITE        0x04
50#define SRMMU_VALID        0x02 /* SRMMU_ET_PTE */
51#define SRMMU_PRIV         0x1c
52#define SRMMU_PRIV_RDONLY  0x18
53
54#define SRMMU_CHG_MASK    (0xffffff00 | SRMMU_REF | SRMMU_DIRTY)
55
56/* SRMMU swap entry encoding */
57#define SRMMU_SWP_TYPE_MASK	0x1f
58#define SRMMU_SWP_TYPE_SHIFT	7
59#define SRMMU_SWP_OFF_MASK	0xfffff
60#define SRMMU_SWP_OFF_SHIFT	(SRMMU_SWP_TYPE_SHIFT + 5)
61/* We borrow bit 6 to store the exclusive marker in swap PTEs. */
62#define SRMMU_SWP_EXCLUSIVE	SRMMU_DIRTY
63
64/* Some day I will implement true fine grained access bits for
65 * user pages because the SRMMU gives us the capabilities to
66 * enforce all the protection levels that vma's can have.
67 * XXX But for now...
68 */
69#define SRMMU_PAGE_NONE    __pgprot(SRMMU_CACHE | \
70				    SRMMU_PRIV | SRMMU_REF)
71#define SRMMU_PAGE_SHARED  __pgprot(SRMMU_VALID | SRMMU_CACHE | \
72				    SRMMU_EXEC | SRMMU_WRITE | SRMMU_REF)
73#define SRMMU_PAGE_COPY    __pgprot(SRMMU_VALID | SRMMU_CACHE | \
74				    SRMMU_EXEC | SRMMU_REF)
75#define SRMMU_PAGE_RDONLY  __pgprot(SRMMU_VALID | SRMMU_CACHE | \
76				    SRMMU_EXEC | SRMMU_REF)
77#define SRMMU_PAGE_KERNEL  __pgprot(SRMMU_VALID | SRMMU_CACHE | SRMMU_PRIV | \
78				    SRMMU_DIRTY | SRMMU_REF)
79
80/* SRMMU Register addresses in ASI 0x4.  These are valid for all
81 * current SRMMU implementations that exist.
82 */
83#define SRMMU_CTRL_REG           0x00000000
84#define SRMMU_CTXTBL_PTR         0x00000100
85#define SRMMU_CTX_REG            0x00000200
86#define SRMMU_FAULT_STATUS       0x00000300
87#define SRMMU_FAULT_ADDR         0x00000400
88
89#define WINDOW_FLUSH(tmp1, tmp2)					\
90	mov	0, tmp1;						\
9198:	ld	[%g6 + TI_UWINMASK], tmp2;				\
92	orcc	%g0, tmp2, %g0;						\
93	add	tmp1, 1, tmp1;						\
94	bne	98b;							\
95	 save	%sp, -64, %sp;						\
9699:	subcc	tmp1, 1, tmp1;						\
97	bne	99b;							\
98	 restore %g0, %g0, %g0;
99
100#ifndef __ASSEMBLY__
101extern unsigned long last_valid_pfn;
102
103/* This makes sense. Honest it does - Anton */
104/* XXX Yes but it's ugly as sin.  FIXME. -KMW */
105extern void *srmmu_nocache_pool;
106#define __nocache_pa(VADDR) (((unsigned long)VADDR) - SRMMU_NOCACHE_VADDR + __pa((unsigned long)srmmu_nocache_pool))
107#define __nocache_va(PADDR) (__va((unsigned long)PADDR) - (unsigned long)srmmu_nocache_pool + SRMMU_NOCACHE_VADDR)
108#define __nocache_fix(VADDR) ((__typeof__(VADDR))__va(__nocache_pa(VADDR)))
109
110/* Accessing the MMU control register. */
111unsigned int srmmu_get_mmureg(void);
112void srmmu_set_mmureg(unsigned long regval);
113void srmmu_set_ctable_ptr(unsigned long paddr);
114void srmmu_set_context(int context);
115int srmmu_get_context(void);
116unsigned int srmmu_get_fstatus(void);
117unsigned int srmmu_get_faddr(void);
118
119/* This is guaranteed on all SRMMU's. */
120static inline void srmmu_flush_whole_tlb(void)
121{
122	__asm__ __volatile__("sta %%g0, [%0] %1\n\t": :
123			     "r" (0x400),        /* Flush entire TLB!! */
124			     "i" (ASI_M_FLUSH_PROBE) : "memory");
125
126}
127
128static inline int
129srmmu_get_pte (unsigned long addr)
130{
131	register unsigned long entry;
132
133	__asm__ __volatile__("\n\tlda [%1] %2,%0\n\t" :
134				"=r" (entry):
135				"r" ((addr & 0xfffff000) | 0x400), "i" (ASI_M_FLUSH_PROBE));
136	return entry;
137}
138
139#endif /* !(__ASSEMBLY__) */
140
141#endif /* !(_SPARC_PGTSRMMU_H) */
142