xref: /linux/arch/microblaze/include/asm/mmu.h (revision e27ecdd94d81e5bc3d1f68591701db5adb342f0d)
1 /*
2  * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
3  * Copyright (C) 2008-2009 PetaLogix
4  * Copyright (C) 2006 Atmark Techno, Inc.
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License. See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 
11 #ifndef _ASM_MICROBLAZE_MMU_H
12 #define _ASM_MICROBLAZE_MMU_H
13 
14 # ifndef CONFIG_MMU
15 #  ifndef __ASSEMBLY__
16 typedef struct {
17 	struct vm_list_struct	*vmlist;
18 	unsigned long		end_brk;
19 } mm_context_t;
20 #  endif /* __ASSEMBLY__ */
21 # else /* CONFIG_MMU */
22 #  ifdef __KERNEL__
23 #   ifndef __ASSEMBLY__
24 
25 /* Default "unsigned long" context */
26 typedef unsigned long mm_context_t;
27 
28 /* Hardware Page Table Entry */
29 typedef struct _PTE {
30 	unsigned long    v:1;	/* Entry is valid */
31 	unsigned long vsid:24;	/* Virtual segment identifier */
32 	unsigned long    h:1;	/* Hash algorithm indicator */
33 	unsigned long  api:6;	/* Abbreviated page index */
34 	unsigned long  rpn:20;	/* Real (physical) page number */
35 	unsigned long     :3;	/* Unused */
36 	unsigned long    r:1;	/* Referenced */
37 	unsigned long    c:1;	/* Changed */
38 	unsigned long    w:1;	/* Write-thru cache mode */
39 	unsigned long    i:1;	/* Cache inhibited */
40 	unsigned long    m:1;	/* Memory coherence */
41 	unsigned long    g:1;	/* Guarded */
42 	unsigned long     :1;	/* Unused */
43 	unsigned long   pp:2;	/* Page protection */
44 } PTE;
45 
46 /* Values for PP (assumes Ks=0, Kp=1) */
47 #  define PP_RWXX	0 /* Supervisor read/write, User none */
48 #  define PP_RWRX	1 /* Supervisor read/write, User read */
49 #  define PP_RWRW	2 /* Supervisor read/write, User read/write */
50 #  define PP_RXRX	3 /* Supervisor read,       User read */
51 
52 /* Segment Register */
53 typedef struct _SEGREG {
54 	unsigned long    t:1;	/* Normal or I/O  type */
55 	unsigned long   ks:1;	/* Supervisor 'key' (normally 0) */
56 	unsigned long   kp:1;	/* User 'key' (normally 1) */
57 	unsigned long    n:1;	/* No-execute */
58 	unsigned long     :4;	/* Unused */
59 	unsigned long vsid:24;	/* Virtual Segment Identifier */
60 } SEGREG;
61 
62 extern void _tlbie(unsigned long va);	/* invalidate a TLB entry */
63 extern void _tlbia(void);		/* invalidate all TLB entries */
64 #   endif /* __ASSEMBLY__ */
65 
66 /*
67  * The MicroBlaze processor has a TLB architecture identical to PPC-40x. The
68  * instruction and data sides share a unified, 64-entry, semi-associative
69  * TLB which is maintained totally under software control. In addition, the
70  * instruction side has a hardware-managed, 2,4, or 8-entry, fully-associative
71  * TLB which serves as a first level to the shared TLB. These two TLBs are
72  * known as the UTLB and ITLB, respectively.
73  */
74 
75 #  define MICROBLAZE_TLB_SIZE 64
76 
77 /*
78  * TLB entries are defined by a "high" tag portion and a "low" data
79  * portion. The data portion is 32-bits.
80  *
81  * TLB entries are managed entirely under software control by reading,
82  * writing, and searching using the MTS and MFS instructions.
83  */
84 
85 #  define TLB_LO		1
86 #  define TLB_HI		0
87 #  define TLB_DATA		TLB_LO
88 #  define TLB_TAG		TLB_HI
89 
90 /* Tag portion */
91 #  define TLB_EPN_MASK		0xFFFFFC00 /* Effective Page Number */
92 #  define TLB_PAGESZ_MASK	0x00000380
93 #  define TLB_PAGESZ(x)		(((x) & 0x7) << 7)
94 #  define PAGESZ_1K		0
95 #  define PAGESZ_4K		1
96 #  define PAGESZ_16K		2
97 #  define PAGESZ_64K		3
98 #  define PAGESZ_256K		4
99 #  define PAGESZ_1M		5
100 #  define PAGESZ_4M		6
101 #  define PAGESZ_16M		7
102 #  define TLB_VALID		0x00000040 /* Entry is valid */
103 
104 /* Data portion */
105 #  define TLB_RPN_MASK		0xFFFFFC00 /* Real Page Number */
106 #  define TLB_PERM_MASK		0x00000300
107 #  define TLB_EX		0x00000200 /* Instruction execution allowed */
108 #  define TLB_WR		0x00000100 /* Writes permitted */
109 #  define TLB_ZSEL_MASK		0x000000F0
110 #  define TLB_ZSEL(x)		(((x) & 0xF) << 4)
111 #  define TLB_ATTR_MASK		0x0000000F
112 #  define TLB_W			0x00000008 /* Caching is write-through */
113 #  define TLB_I			0x00000004 /* Caching is inhibited */
114 #  define TLB_M			0x00000002 /* Memory is coherent */
115 #  define TLB_G			0x00000001 /* Memory is guarded from prefetch */
116 
117 #  endif /* __KERNEL__ */
118 # endif /* CONFIG_MMU */
119 #endif /* _ASM_MICROBLAZE_MMU_H */
120