xref: /openbmc/linux/arch/microblaze/include/asm/mmu.h (revision e15a5365)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
4  * Copyright (C) 2008-2009 PetaLogix
5  * Copyright (C) 2006 Atmark Techno, Inc.
6  */
7 
8 #ifndef _ASM_MICROBLAZE_MMU_H
9 #define _ASM_MICROBLAZE_MMU_H
10 
11 # ifndef CONFIG_MMU
12 #  include <asm-generic/mmu.h>
13 # else /* CONFIG_MMU */
14 #  ifdef __KERNEL__
15 #   ifndef __ASSEMBLY__
16 
17 /* Default "unsigned long" context */
18 typedef unsigned long mm_context_t;
19 
20 /* Hardware Page Table Entry */
21 typedef struct _PTE {
22 	unsigned long    v:1;	/* Entry is valid */
23 	unsigned long vsid:24;	/* Virtual segment identifier */
24 	unsigned long    h:1;	/* Hash algorithm indicator */
25 	unsigned long  api:6;	/* Abbreviated page index */
26 	unsigned long  rpn:20;	/* Real (physical) page number */
27 	unsigned long     :3;	/* Unused */
28 	unsigned long    r:1;	/* Referenced */
29 	unsigned long    c:1;	/* Changed */
30 	unsigned long    w:1;	/* Write-thru cache mode */
31 	unsigned long    i:1;	/* Cache inhibited */
32 	unsigned long    m:1;	/* Memory coherence */
33 	unsigned long    g:1;	/* Guarded */
34 	unsigned long     :1;	/* Unused */
35 	unsigned long   pp:2;	/* Page protection */
36 } PTE;
37 
38 /* Values for PP (assumes Ks=0, Kp=1) */
39 #  define PP_RWXX	0 /* Supervisor read/write, User none */
40 #  define PP_RWRX	1 /* Supervisor read/write, User read */
41 #  define PP_RWRW	2 /* Supervisor read/write, User read/write */
42 #  define PP_RXRX	3 /* Supervisor read,       User read */
43 
44 /* Segment Register */
45 typedef struct _SEGREG {
46 	unsigned long    t:1;	/* Normal or I/O  type */
47 	unsigned long   ks:1;	/* Supervisor 'key' (normally 0) */
48 	unsigned long   kp:1;	/* User 'key' (normally 1) */
49 	unsigned long    n:1;	/* No-execute */
50 	unsigned long     :4;	/* Unused */
51 	unsigned long vsid:24;	/* Virtual Segment Identifier */
52 } SEGREG;
53 
54 extern void _tlbie(unsigned long va);	/* invalidate a TLB entry */
55 extern void _tlbia(void);		/* invalidate all TLB entries */
56 
57 /*
58  * tlb_skip size stores actual number skipped TLBs from TLB0 - every directy TLB
59  * mapping has to increase tlb_skip size.
60  */
61 extern u32 tlb_skip;
62 #   endif /* __ASSEMBLY__ */
63 
64 /*
65  * The MicroBlaze processor has a TLB architecture identical to PPC-40x. The
66  * instruction and data sides share a unified, 64-entry, semi-associative
67  * TLB which is maintained totally under software control. In addition, the
68  * instruction side has a hardware-managed, 2,4, or 8-entry, fully-associative
69  * TLB which serves as a first level to the shared TLB. These two TLBs are
70  * known as the UTLB and ITLB, respectively.
71  */
72 
73 #  define MICROBLAZE_TLB_SIZE 64
74 
75 /* For cases when you want to skip some TLB entries */
76 #  define MICROBLAZE_TLB_SKIP 0
77 
78 /* Use the last TLB for temporary access to LMB */
79 #  define MICROBLAZE_LMB_TLB_ID 63
80 
81 /*
82  * TLB entries are defined by a "high" tag portion and a "low" data
83  * portion. The data portion is 32-bits.
84  *
85  * TLB entries are managed entirely under software control by reading,
86  * writing, and searching using the MTS and MFS instructions.
87  */
88 
89 #  define TLB_LO		1
90 #  define TLB_HI		0
91 #  define TLB_DATA		TLB_LO
92 #  define TLB_TAG		TLB_HI
93 
94 /* Tag portion */
95 #  define TLB_EPN_MASK		0xFFFFFC00 /* Effective Page Number */
96 #  define TLB_PAGESZ_MASK	0x00000380
97 #  define TLB_PAGESZ(x)		(((x) & 0x7) << 7)
98 #  define PAGESZ_1K		0
99 #  define PAGESZ_4K		1
100 #  define PAGESZ_16K		2
101 #  define PAGESZ_64K		3
102 #  define PAGESZ_256K		4
103 #  define PAGESZ_1M		5
104 #  define PAGESZ_4M		6
105 #  define PAGESZ_16M		7
106 #  define TLB_VALID		0x00000040 /* Entry is valid */
107 
108 /* Data portion */
109 #  define TLB_RPN_MASK		0xFFFFFC00 /* Real Page Number */
110 #  define TLB_PERM_MASK		0x00000300
111 #  define TLB_EX		0x00000200 /* Instruction execution allowed */
112 #  define TLB_WR		0x00000100 /* Writes permitted */
113 #  define TLB_ZSEL_MASK		0x000000F0
114 #  define TLB_ZSEL(x)		(((x) & 0xF) << 4)
115 #  define TLB_ATTR_MASK		0x0000000F
116 #  define TLB_W			0x00000008 /* Caching is write-through */
117 #  define TLB_I			0x00000004 /* Caching is inhibited */
118 #  define TLB_M			0x00000002 /* Memory is coherent */
119 #  define TLB_G			0x00000001 /* Memory is guarded from prefetch */
120 
121 #  endif /* __KERNEL__ */
122 # endif /* CONFIG_MMU */
123 #endif /* _ASM_MICROBLAZE_MMU_H */
124