1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_MMU_8XX_H_
3 #define _ASM_POWERPC_MMU_8XX_H_
4 /*
5  * PPC8xx support
6  */
7 
8 /* Control/status registers for the MPC8xx.
9  * A write operation to these registers causes serialized access.
10  * During software tablewalk, the registers used perform mask/shift-add
11  * operations when written/read.  A TLB entry is created when the Mx_RPN
12  * is written, and the contents of several registers are used to
13  * create the entry.
14  */
15 #define SPRN_MI_CTR	784	/* Instruction TLB control register */
16 #define MI_GPM		0x80000000	/* Set domain manager mode */
17 #define MI_PPM		0x40000000	/* Set subpage protection */
18 #define MI_CIDEF	0x20000000	/* Set cache inhibit when MMU dis */
19 #define MI_RSV4I	0x08000000	/* Reserve 4 TLB entries */
20 #define MI_PPCS		0x02000000	/* Use MI_RPN prob/priv state */
21 #define MI_IDXMASK	0x00001f00	/* TLB index to be loaded */
22 
23 /* These are the Ks and Kp from the PowerPC books.  For proper operation,
24  * Ks = 0, Kp = 1.
25  */
26 #define SPRN_MI_AP	786
27 #define MI_Ks		0x80000000	/* Should not be set */
28 #define MI_Kp		0x40000000	/* Should always be set */
29 
30 /*
31  * All pages' PP data bits are set to either 001 or 011 by copying _PAGE_EXEC
32  * into bit 21 in the ITLBmiss handler (bit 21 is the middle bit), which means
33  * respectively NA for All or X for Supervisor and no access for User.
34  * Then we use the APG to say whether accesses are according to Page rules or
35  * "all Supervisor" rules (Access to all)
36  * _PAGE_ACCESSED is also managed via APG. When _PAGE_ACCESSED is not set, say
37  * "all User" rules, that will lead to NA for all.
38  * Therefore, we define 4 APG groups. lsb is _PAGE_ACCESSED
39  * 0 => Kernel => 11 (all accesses performed according as user iaw page definition)
40  * 1 => Kernel+Accessed => 01 (all accesses performed according to page definition)
41  * 2 => User => 11 (all accesses performed according as user iaw page definition)
42  * 3 => User+Accessed => 00 (all accesses performed as supervisor iaw page definition) for INIT
43  *                    => 10 (all accesses performed according to swaped page definition) for KUEP
44  * 4-15 => Not Used
45  */
46 #define MI_APG_INIT	0xdc000000
47 #define MI_APG_KUEP	0xde000000
48 
49 /* The effective page number register.  When read, contains the information
50  * about the last instruction TLB miss.  When MI_RPN is written, bits in
51  * this register are used to create the TLB entry.
52  */
53 #define SPRN_MI_EPN	787
54 #define MI_EPNMASK	0xfffff000	/* Effective page number for entry */
55 #define MI_EVALID	0x00000200	/* Entry is valid */
56 #define MI_ASIDMASK	0x0000000f	/* ASID match value */
57 					/* Reset value is undefined */
58 
59 /* A "level 1" or "segment" or whatever you want to call it register.
60  * For the instruction TLB, it contains bits that get loaded into the
61  * TLB entry when the MI_RPN is written.
62  */
63 #define SPRN_MI_TWC	789
64 #define MI_APG		0x000001e0	/* Access protection group (0) */
65 #define MI_GUARDED	0x00000010	/* Guarded storage */
66 #define MI_PSMASK	0x0000000c	/* Mask of page size bits */
67 #define MI_PS8MEG	0x0000000c	/* 8M page size */
68 #define MI_PS512K	0x00000004	/* 512K page size */
69 #define MI_PS4K_16K	0x00000000	/* 4K or 16K page size */
70 #define MI_SVALID	0x00000001	/* Segment entry is valid */
71 					/* Reset value is undefined */
72 
73 /* Real page number.  Defined by the pte.  Writing this register
74  * causes a TLB entry to be created for the instruction TLB, using
75  * additional information from the MI_EPN, and MI_TWC registers.
76  */
77 #define SPRN_MI_RPN	790
78 #define MI_SPS16K	0x00000008	/* Small page size (0 = 4k, 1 = 16k) */
79 
80 /* Define an RPN value for mapping kernel memory to large virtual
81  * pages for boot initialization.  This has real page number of 0,
82  * large page size, shared page, cache enabled, and valid.
83  * Also mark all subpages valid and write access.
84  */
85 #define MI_BOOTINIT	0x000001fd
86 
87 #define SPRN_MD_CTR	792	/* Data TLB control register */
88 #define MD_GPM		0x80000000	/* Set domain manager mode */
89 #define MD_PPM		0x40000000	/* Set subpage protection */
90 #define MD_CIDEF	0x20000000	/* Set cache inhibit when MMU dis */
91 #define MD_WTDEF	0x10000000	/* Set writethrough when MMU dis */
92 #define MD_RSV4I	0x08000000	/* Reserve 4 TLB entries */
93 #define MD_TWAM		0x04000000	/* Use 4K page hardware assist */
94 #define MD_PPCS		0x02000000	/* Use MI_RPN prob/priv state */
95 #define MD_IDXMASK	0x00001f00	/* TLB index to be loaded */
96 
97 #define SPRN_M_CASID	793	/* Address space ID (context) to match */
98 #define MC_ASIDMASK	0x0000000f	/* Bits used for ASID value */
99 
100 
101 /* These are the Ks and Kp from the PowerPC books.  For proper operation,
102  * Ks = 0, Kp = 1.
103  */
104 #define SPRN_MD_AP	794
105 #define MD_Ks		0x80000000	/* Should not be set */
106 #define MD_Kp		0x40000000	/* Should always be set */
107 
108 /* See explanation above at the definition of MI_APG_INIT */
109 #define MD_APG_INIT	0xdc000000
110 #define MD_APG_KUAP	0xde000000
111 
112 /* The effective page number register.  When read, contains the information
113  * about the last instruction TLB miss.  When MD_RPN is written, bits in
114  * this register are used to create the TLB entry.
115  */
116 #define SPRN_MD_EPN	795
117 #define MD_EPNMASK	0xfffff000	/* Effective page number for entry */
118 #define MD_EVALID	0x00000200	/* Entry is valid */
119 #define MD_ASIDMASK	0x0000000f	/* ASID match value */
120 					/* Reset value is undefined */
121 
122 /* The pointer to the base address of the first level page table.
123  * During a software tablewalk, reading this register provides the address
124  * of the entry associated with MD_EPN.
125  */
126 #define SPRN_M_TWB	796
127 #define	M_L1TB		0xfffff000	/* Level 1 table base address */
128 #define M_L1INDX	0x00000ffc	/* Level 1 index, when read */
129 					/* Reset value is undefined */
130 
131 /* A "level 1" or "segment" or whatever you want to call it register.
132  * For the data TLB, it contains bits that get loaded into the TLB entry
133  * when the MD_RPN is written.  It is also provides the hardware assist
134  * for finding the PTE address during software tablewalk.
135  */
136 #define SPRN_MD_TWC	797
137 #define MD_L2TB		0xfffff000	/* Level 2 table base address */
138 #define MD_L2INDX	0xfffffe00	/* Level 2 index (*pte), when read */
139 #define MD_APG		0x000001e0	/* Access protection group (0) */
140 #define MD_GUARDED	0x00000010	/* Guarded storage */
141 #define MD_PSMASK	0x0000000c	/* Mask of page size bits */
142 #define MD_PS8MEG	0x0000000c	/* 8M page size */
143 #define MD_PS512K	0x00000004	/* 512K page size */
144 #define MD_PS4K_16K	0x00000000	/* 4K or 16K page size */
145 #define MD_WT		0x00000002	/* Use writethrough page attribute */
146 #define MD_SVALID	0x00000001	/* Segment entry is valid */
147 					/* Reset value is undefined */
148 
149 
150 /* Real page number.  Defined by the pte.  Writing this register
151  * causes a TLB entry to be created for the data TLB, using
152  * additional information from the MD_EPN, and MD_TWC registers.
153  */
154 #define SPRN_MD_RPN	798
155 #define MD_SPS16K	0x00000008	/* Small page size (0 = 4k, 1 = 16k) */
156 
157 /* This is a temporary storage register that could be used to save
158  * a processor working register during a tablewalk.
159  */
160 #define SPRN_M_TW	799
161 
162 #if defined(CONFIG_PPC_4K_PAGES)
163 #define mmu_virtual_psize	MMU_PAGE_4K
164 #elif defined(CONFIG_PPC_16K_PAGES)
165 #define mmu_virtual_psize	MMU_PAGE_16K
166 #define PTE_FRAG_NR		4
167 #define PTE_FRAG_SIZE_SHIFT	12
168 #define PTE_FRAG_SIZE		(1UL << 12)
169 #else
170 #error "Unsupported PAGE_SIZE"
171 #endif
172 
173 #define mmu_linear_psize	MMU_PAGE_8M
174 
175 #ifndef __ASSEMBLY__
176 
177 #include <linux/mmdebug.h>
178 
179 void mmu_pin_tlb(unsigned long top, bool readonly);
180 
181 typedef struct {
182 	unsigned int id;
183 	unsigned int active;
184 	void __user *vdso;
185 	void *pte_frag;
186 } mm_context_t;
187 
188 #define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000)
189 #define VIRT_IMMR_BASE (__fix_to_virt(FIX_IMMR_BASE))
190 
191 /* Page size definitions, common between 32 and 64-bit
192  *
193  *    shift : is the "PAGE_SHIFT" value for that page size
194  *    penc  : is the pte encoding mask
195  *
196  */
197 struct mmu_psize_def {
198 	unsigned int	shift;	/* number of bits */
199 	unsigned int	enc;	/* PTE encoding */
200 	unsigned int    ind;    /* Corresponding indirect page size shift */
201 	unsigned int	flags;
202 #define MMU_PAGE_SIZE_DIRECT	0x1	/* Supported as a direct size */
203 #define MMU_PAGE_SIZE_INDIRECT	0x2	/* Supported as an indirect size */
204 };
205 
206 extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
207 
208 static inline int shift_to_mmu_psize(unsigned int shift)
209 {
210 	int psize;
211 
212 	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize)
213 		if (mmu_psize_defs[psize].shift == shift)
214 			return psize;
215 	return -1;
216 }
217 
218 static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
219 {
220 	if (mmu_psize_defs[mmu_psize].shift)
221 		return mmu_psize_defs[mmu_psize].shift;
222 	BUG();
223 }
224 
225 /* patch sites */
226 extern s32 patch__itlbmiss_exit_1, patch__dtlbmiss_exit_1;
227 extern s32 patch__itlbmiss_perf, patch__dtlbmiss_perf;
228 
229 #endif /* !__ASSEMBLY__ */
230 
231 #endif /* _ASM_POWERPC_MMU_8XX_H_ */
232