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 #  include <asm-generic/mmu.h>
16 # else /* CONFIG_MMU */
17 #  ifdef __KERNEL__
18 #   ifndef __ASSEMBLY__
19 
20 /* Default "unsigned long" context */
21 typedef unsigned long mm_context_t;
22 
23 /* Hardware Page Table Entry */
24 typedef struct _PTE {
25 	unsigned long    v:1;	/* Entry is valid */
26 	unsigned long vsid:24;	/* Virtual segment identifier */
27 	unsigned long    h:1;	/* Hash algorithm indicator */
28 	unsigned long  api:6;	/* Abbreviated page index */
29 	unsigned long  rpn:20;	/* Real (physical) page number */
30 	unsigned long     :3;	/* Unused */
31 	unsigned long    r:1;	/* Referenced */
32 	unsigned long    c:1;	/* Changed */
33 	unsigned long    w:1;	/* Write-thru cache mode */
34 	unsigned long    i:1;	/* Cache inhibited */
35 	unsigned long    m:1;	/* Memory coherence */
36 	unsigned long    g:1;	/* Guarded */
37 	unsigned long     :1;	/* Unused */
38 	unsigned long   pp:2;	/* Page protection */
39 } PTE;
40 
41 /* Values for PP (assumes Ks=0, Kp=1) */
42 #  define PP_RWXX	0 /* Supervisor read/write, User none */
43 #  define PP_RWRX	1 /* Supervisor read/write, User read */
44 #  define PP_RWRW	2 /* Supervisor read/write, User read/write */
45 #  define PP_RXRX	3 /* Supervisor read,       User read */
46 
47 /* Segment Register */
48 typedef struct _SEGREG {
49 	unsigned long    t:1;	/* Normal or I/O  type */
50 	unsigned long   ks:1;	/* Supervisor 'key' (normally 0) */
51 	unsigned long   kp:1;	/* User 'key' (normally 1) */
52 	unsigned long    n:1;	/* No-execute */
53 	unsigned long     :4;	/* Unused */
54 	unsigned long vsid:24;	/* Virtual Segment Identifier */
55 } SEGREG;
56 
57 extern void _tlbie(unsigned long va);	/* invalidate a TLB entry */
58 extern void _tlbia(void);		/* invalidate all TLB entries */
59 
60 /*
61  * tlb_skip size stores actual number skipped TLBs from TLB0 - every directy TLB
62  * mapping has to increase tlb_skip size.
63  */
64 extern u32 tlb_skip;
65 #   endif /* __ASSEMBLY__ */
66 
67 /*
68  * The MicroBlaze processor has a TLB architecture identical to PPC-40x. The
69  * instruction and data sides share a unified, 64-entry, semi-associative
70  * TLB which is maintained totally under software control. In addition, the
71  * instruction side has a hardware-managed, 2,4, or 8-entry, fully-associative
72  * TLB which serves as a first level to the shared TLB. These two TLBs are
73  * known as the UTLB and ITLB, respectively.
74  */
75 
76 #  define MICROBLAZE_TLB_SIZE 64
77 
78 /* For cases when you want to skip some TLB entries */
79 #  define MICROBLAZE_TLB_SKIP 0
80 
81 /* Use the last TLB for temporary access to LMB */
82 #  define MICROBLAZE_LMB_TLB_ID 63
83 
84 /*
85  * TLB entries are defined by a "high" tag portion and a "low" data
86  * portion. The data portion is 32-bits.
87  *
88  * TLB entries are managed entirely under software control by reading,
89  * writing, and searching using the MTS and MFS instructions.
90  */
91 
92 #  define TLB_LO		1
93 #  define TLB_HI		0
94 #  define TLB_DATA		TLB_LO
95 #  define TLB_TAG		TLB_HI
96 
97 /* Tag portion */
98 #  define TLB_EPN_MASK		0xFFFFFC00 /* Effective Page Number */
99 #  define TLB_PAGESZ_MASK	0x00000380
100 #  define TLB_PAGESZ(x)		(((x) & 0x7) << 7)
101 #  define PAGESZ_1K		0
102 #  define PAGESZ_4K		1
103 #  define PAGESZ_16K		2
104 #  define PAGESZ_64K		3
105 #  define PAGESZ_256K		4
106 #  define PAGESZ_1M		5
107 #  define PAGESZ_4M		6
108 #  define PAGESZ_16M		7
109 #  define TLB_VALID		0x00000040 /* Entry is valid */
110 
111 /* Data portion */
112 #  define TLB_RPN_MASK		0xFFFFFC00 /* Real Page Number */
113 #  define TLB_PERM_MASK		0x00000300
114 #  define TLB_EX		0x00000200 /* Instruction execution allowed */
115 #  define TLB_WR		0x00000100 /* Writes permitted */
116 #  define TLB_ZSEL_MASK		0x000000F0
117 #  define TLB_ZSEL(x)		(((x) & 0xF) << 4)
118 #  define TLB_ATTR_MASK		0x0000000F
119 #  define TLB_W			0x00000008 /* Caching is write-through */
120 #  define TLB_I			0x00000004 /* Caching is inhibited */
121 #  define TLB_M			0x00000002 /* Memory is coherent */
122 #  define TLB_G			0x00000001 /* Memory is guarded from prefetch */
123 
124 #  endif /* __KERNEL__ */
125 # endif /* CONFIG_MMU */
126 #endif /* _ASM_MICROBLAZE_MMU_H */
127