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  * Therefore, we define 2 APG groups. lsb is _PMD_USER
37  * 0 => Kernel => 01 (all accesses performed according to page definition)
38  * 1 => User => 00 (all accesses performed as supervisor iaw page definition)
39  * 2-15 => Not Used
40  */
41 #define MI_APG_INIT	0x40000000
42 
43 /*
44  * 0 => Kernel => 01 (all accesses performed according to page definition)
45  * 1 => User => 10 (all accesses performed according to swaped page definition)
46  * 2-15 => Not Used
47  */
48 #define MI_APG_KUEP	0x60000000
49 
50 /* The effective page number register.  When read, contains the information
51  * about the last instruction TLB miss.  When MI_RPN is written, bits in
52  * this register are used to create the TLB entry.
53  */
54 #define SPRN_MI_EPN	787
55 #define MI_EPNMASK	0xfffff000	/* Effective page number for entry */
56 #define MI_EVALID	0x00000200	/* Entry is valid */
57 #define MI_ASIDMASK	0x0000000f	/* ASID match value */
58 					/* Reset value is undefined */
59 
60 /* A "level 1" or "segment" or whatever you want to call it register.
61  * For the instruction TLB, it contains bits that get loaded into the
62  * TLB entry when the MI_RPN is written.
63  */
64 #define SPRN_MI_TWC	789
65 #define MI_APG		0x000001e0	/* Access protection group (0) */
66 #define MI_GUARDED	0x00000010	/* Guarded storage */
67 #define MI_PSMASK	0x0000000c	/* Mask of page size bits */
68 #define MI_PS8MEG	0x0000000c	/* 8M page size */
69 #define MI_PS512K	0x00000004	/* 512K page size */
70 #define MI_PS4K_16K	0x00000000	/* 4K or 16K page size */
71 #define MI_SVALID	0x00000001	/* Segment entry is valid */
72 					/* Reset value is undefined */
73 
74 /* Real page number.  Defined by the pte.  Writing this register
75  * causes a TLB entry to be created for the instruction TLB, using
76  * additional information from the MI_EPN, and MI_TWC registers.
77  */
78 #define SPRN_MI_RPN	790
79 #define MI_SPS16K	0x00000008	/* Small page size (0 = 4k, 1 = 16k) */
80 
81 /* Define an RPN value for mapping kernel memory to large virtual
82  * pages for boot initialization.  This has real page number of 0,
83  * large page size, shared page, cache enabled, and valid.
84  * Also mark all subpages valid and write access.
85  */
86 #define MI_BOOTINIT	0x000001fd
87 
88 #define SPRN_MD_CTR	792	/* Data TLB control register */
89 #define MD_GPM		0x80000000	/* Set domain manager mode */
90 #define MD_PPM		0x40000000	/* Set subpage protection */
91 #define MD_CIDEF	0x20000000	/* Set cache inhibit when MMU dis */
92 #define MD_WTDEF	0x10000000	/* Set writethrough when MMU dis */
93 #define MD_RSV4I	0x08000000	/* Reserve 4 TLB entries */
94 #define MD_TWAM		0x04000000	/* Use 4K page hardware assist */
95 #define MD_PPCS		0x02000000	/* Use MI_RPN prob/priv state */
96 #define MD_IDXMASK	0x00001f00	/* TLB index to be loaded */
97 
98 #define SPRN_M_CASID	793	/* Address space ID (context) to match */
99 #define MC_ASIDMASK	0x0000000f	/* Bits used for ASID value */
100 
101 
102 /* These are the Ks and Kp from the PowerPC books.  For proper operation,
103  * Ks = 0, Kp = 1.
104  */
105 #define SPRN_MD_AP	794
106 #define MD_Ks		0x80000000	/* Should not be set */
107 #define MD_Kp		0x40000000	/* Should always be set */
108 
109 /*
110  * All pages' PP data bits are set to either 000 or 011 or 001, which means
111  * respectively RW for Supervisor and no access for User, or RO for
112  * Supervisor and no access for user and NA for ALL.
113  * Then we use the APG to say whether accesses are according to Page rules or
114  * "all Supervisor" rules (Access to all)
115  * Therefore, we define 2 APG groups. lsb is _PMD_USER
116  * 0 => Kernel => 01 (all accesses performed according to page definition)
117  * 1 => User => 00 (all accesses performed as supervisor iaw page definition)
118  * 2-15 => Not Used
119  */
120 #define MD_APG_INIT	0x40000000
121 
122 /*
123  * 0 => No user => 01 (all accesses performed according to page definition)
124  * 1 => User => 10 (all accesses performed according to swaped page definition)
125  * 2-15 => Not Used
126  */
127 #define MD_APG_KUAP	0x60000000
128 
129 /* The effective page number register.  When read, contains the information
130  * about the last instruction TLB miss.  When MD_RPN is written, bits in
131  * this register are used to create the TLB entry.
132  */
133 #define SPRN_MD_EPN	795
134 #define MD_EPNMASK	0xfffff000	/* Effective page number for entry */
135 #define MD_EVALID	0x00000200	/* Entry is valid */
136 #define MD_ASIDMASK	0x0000000f	/* ASID match value */
137 					/* Reset value is undefined */
138 
139 /* The pointer to the base address of the first level page table.
140  * During a software tablewalk, reading this register provides the address
141  * of the entry associated with MD_EPN.
142  */
143 #define SPRN_M_TWB	796
144 #define	M_L1TB		0xfffff000	/* Level 1 table base address */
145 #define M_L1INDX	0x00000ffc	/* Level 1 index, when read */
146 					/* Reset value is undefined */
147 
148 /* A "level 1" or "segment" or whatever you want to call it register.
149  * For the data TLB, it contains bits that get loaded into the TLB entry
150  * when the MD_RPN is written.  It is also provides the hardware assist
151  * for finding the PTE address during software tablewalk.
152  */
153 #define SPRN_MD_TWC	797
154 #define MD_L2TB		0xfffff000	/* Level 2 table base address */
155 #define MD_L2INDX	0xfffffe00	/* Level 2 index (*pte), when read */
156 #define MD_APG		0x000001e0	/* Access protection group (0) */
157 #define MD_GUARDED	0x00000010	/* Guarded storage */
158 #define MD_PSMASK	0x0000000c	/* Mask of page size bits */
159 #define MD_PS8MEG	0x0000000c	/* 8M page size */
160 #define MD_PS512K	0x00000004	/* 512K page size */
161 #define MD_PS4K_16K	0x00000000	/* 4K or 16K page size */
162 #define MD_WT		0x00000002	/* Use writethrough page attribute */
163 #define MD_SVALID	0x00000001	/* Segment entry is valid */
164 					/* Reset value is undefined */
165 
166 
167 /* Real page number.  Defined by the pte.  Writing this register
168  * causes a TLB entry to be created for the data TLB, using
169  * additional information from the MD_EPN, and MD_TWC registers.
170  */
171 #define SPRN_MD_RPN	798
172 #define MD_SPS16K	0x00000008	/* Small page size (0 = 4k, 1 = 16k) */
173 
174 /* This is a temporary storage register that could be used to save
175  * a processor working register during a tablewalk.
176  */
177 #define SPRN_M_TW	799
178 
179 #if defined(CONFIG_PPC_4K_PAGES)
180 #define mmu_virtual_psize	MMU_PAGE_4K
181 #elif defined(CONFIG_PPC_16K_PAGES)
182 #define mmu_virtual_psize	MMU_PAGE_16K
183 #define PTE_FRAG_NR		4
184 #define PTE_FRAG_SIZE_SHIFT	12
185 #define PTE_FRAG_SIZE		(1UL << 12)
186 #else
187 #error "Unsupported PAGE_SIZE"
188 #endif
189 
190 #define mmu_linear_psize	MMU_PAGE_8M
191 
192 #ifndef __ASSEMBLY__
193 
194 #include <linux/mmdebug.h>
195 
196 void mmu_pin_tlb(unsigned long top, bool readonly);
197 
198 typedef struct {
199 	unsigned int id;
200 	unsigned int active;
201 	unsigned long vdso_base;
202 	void *pte_frag;
203 } mm_context_t;
204 
205 #define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000)
206 #define VIRT_IMMR_BASE (__fix_to_virt(FIX_IMMR_BASE))
207 
208 /* Page size definitions, common between 32 and 64-bit
209  *
210  *    shift : is the "PAGE_SHIFT" value for that page size
211  *    penc  : is the pte encoding mask
212  *
213  */
214 struct mmu_psize_def {
215 	unsigned int	shift;	/* number of bits */
216 	unsigned int	enc;	/* PTE encoding */
217 	unsigned int    ind;    /* Corresponding indirect page size shift */
218 	unsigned int	flags;
219 #define MMU_PAGE_SIZE_DIRECT	0x1	/* Supported as a direct size */
220 #define MMU_PAGE_SIZE_INDIRECT	0x2	/* Supported as an indirect size */
221 };
222 
223 extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
224 
225 static inline int shift_to_mmu_psize(unsigned int shift)
226 {
227 	int psize;
228 
229 	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize)
230 		if (mmu_psize_defs[psize].shift == shift)
231 			return psize;
232 	return -1;
233 }
234 
235 static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
236 {
237 	if (mmu_psize_defs[mmu_psize].shift)
238 		return mmu_psize_defs[mmu_psize].shift;
239 	BUG();
240 }
241 
242 /* patch sites */
243 extern s32 patch__itlbmiss_exit_1, patch__dtlbmiss_exit_1;
244 extern s32 patch__itlbmiss_perf, patch__dtlbmiss_perf;
245 
246 #endif /* !__ASSEMBLY__ */
247 
248 #endif /* _ASM_POWERPC_MMU_8XX_H_ */
249