1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_PGTABLE_RADIX_H
3 #define _ASM_POWERPC_PGTABLE_RADIX_H
4 
5 #ifndef __ASSEMBLY__
6 #include <asm/cmpxchg.h>
7 #endif
8 
9 #ifdef CONFIG_PPC_64K_PAGES
10 #include <asm/book3s/64/radix-64k.h>
11 #else
12 #include <asm/book3s/64/radix-4k.h>
13 #endif
14 
15 /*
16  * For P9 DD1 only, we need to track whether the pte's huge.
17  */
18 #define R_PAGE_LARGE	_RPAGE_RSV1
19 
20 
21 #ifndef __ASSEMBLY__
22 #include <asm/book3s/64/tlbflush-radix.h>
23 #include <asm/cpu_has_feature.h>
24 #endif
25 
26 /* An empty PTE can still have a R or C writeback */
27 #define RADIX_PTE_NONE_MASK		(_PAGE_DIRTY | _PAGE_ACCESSED)
28 
29 /* Bits to set in a RPMD/RPUD/RPGD */
30 #define RADIX_PMD_VAL_BITS		(0x8000000000000000UL | RADIX_PTE_INDEX_SIZE)
31 #define RADIX_PUD_VAL_BITS		(0x8000000000000000UL | RADIX_PMD_INDEX_SIZE)
32 #define RADIX_PGD_VAL_BITS		(0x8000000000000000UL | RADIX_PUD_INDEX_SIZE)
33 
34 /* Don't have anything in the reserved bits and leaf bits */
35 #define RADIX_PMD_BAD_BITS		0x60000000000000e0UL
36 #define RADIX_PUD_BAD_BITS		0x60000000000000e0UL
37 #define RADIX_PGD_BAD_BITS		0x60000000000000e0UL
38 
39 /*
40  * Size of EA range mapped by our pagetables.
41  */
42 #define RADIX_PGTABLE_EADDR_SIZE (RADIX_PTE_INDEX_SIZE + RADIX_PMD_INDEX_SIZE +	\
43 			      RADIX_PUD_INDEX_SIZE + RADIX_PGD_INDEX_SIZE + PAGE_SHIFT)
44 #define RADIX_PGTABLE_RANGE (ASM_CONST(1) << RADIX_PGTABLE_EADDR_SIZE)
45 
46 /*
47  * We support 52 bit address space, Use top bit for kernel
48  * virtual mapping. Also make sure kernel fit in the top
49  * quadrant.
50  *
51  *           +------------------+
52  *           +------------------+  Kernel virtual map (0xc008000000000000)
53  *           |                  |
54  *           |                  |
55  *           |                  |
56  * 0b11......+------------------+  Kernel linear map (0xc....)
57  *           |                  |
58  *           |     2 quadrant   |
59  *           |                  |
60  * 0b10......+------------------+
61  *           |                  |
62  *           |    1 quadrant    |
63  *           |                  |
64  * 0b01......+------------------+
65  *           |                  |
66  *           |    0 quadrant    |
67  *           |                  |
68  * 0b00......+------------------+
69  *
70  *
71  * 3rd quadrant expanded:
72  * +------------------------------+
73  * |                              |
74  * |                              |
75  * |                              |
76  * +------------------------------+  Kernel IO map end (0xc010000000000000)
77  * |                              |
78  * |                              |
79  * |      1/2 of virtual map      |
80  * |                              |
81  * |                              |
82  * +------------------------------+  Kernel IO map start
83  * |                              |
84  * |      1/4 of virtual map      |
85  * |                              |
86  * +------------------------------+  Kernel vmemap start
87  * |                              |
88  * |     1/4 of virtual map       |
89  * |                              |
90  * +------------------------------+  Kernel virt start (0xc008000000000000)
91  * |                              |
92  * |                              |
93  * |                              |
94  * +------------------------------+  Kernel linear (0xc.....)
95  */
96 
97 #define RADIX_KERN_VIRT_START ASM_CONST(0xc008000000000000)
98 #define RADIX_KERN_VIRT_SIZE  ASM_CONST(0x0008000000000000)
99 
100 /*
101  * The vmalloc space starts at the beginning of that region, and
102  * occupies a quarter of it on radix config.
103  * (we keep a quarter for the virtual memmap)
104  */
105 #define RADIX_VMALLOC_START	RADIX_KERN_VIRT_START
106 #define RADIX_VMALLOC_SIZE	(RADIX_KERN_VIRT_SIZE >> 2)
107 #define RADIX_VMALLOC_END	(RADIX_VMALLOC_START + RADIX_VMALLOC_SIZE)
108 /*
109  * Defines the address of the vmemap area, in its own region on
110  * hash table CPUs.
111  */
112 #define RADIX_VMEMMAP_BASE		(RADIX_VMALLOC_END)
113 
114 #define RADIX_KERN_IO_START	(RADIX_KERN_VIRT_START + (RADIX_KERN_VIRT_SIZE >> 1))
115 
116 #ifndef __ASSEMBLY__
117 #define RADIX_PTE_TABLE_SIZE	(sizeof(pte_t) << RADIX_PTE_INDEX_SIZE)
118 #define RADIX_PMD_TABLE_SIZE	(sizeof(pmd_t) << RADIX_PMD_INDEX_SIZE)
119 #define RADIX_PUD_TABLE_SIZE	(sizeof(pud_t) << RADIX_PUD_INDEX_SIZE)
120 #define RADIX_PGD_TABLE_SIZE	(sizeof(pgd_t) << RADIX_PGD_INDEX_SIZE)
121 
122 #ifdef CONFIG_STRICT_KERNEL_RWX
123 extern void radix__mark_rodata_ro(void);
124 extern void radix__mark_initmem_nx(void);
125 #endif
126 
127 extern void radix__ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep,
128 					 pte_t entry, unsigned long address,
129 					 int psize);
130 
131 static inline unsigned long __radix_pte_update(pte_t *ptep, unsigned long clr,
132 					       unsigned long set)
133 {
134 	__be64 old_be, tmp_be;
135 
136 	__asm__ __volatile__(
137 	"1:	ldarx	%0,0,%3		# pte_update\n"
138 	"	andc	%1,%0,%5	\n"
139 	"	or	%1,%1,%4	\n"
140 	"	stdcx.	%1,0,%3		\n"
141 	"	bne-	1b"
142 	: "=&r" (old_be), "=&r" (tmp_be), "=m" (*ptep)
143 	: "r" (ptep), "r" (cpu_to_be64(set)), "r" (cpu_to_be64(clr))
144 	: "cc" );
145 
146 	return be64_to_cpu(old_be);
147 }
148 
149 static inline unsigned long radix__pte_update(struct mm_struct *mm,
150 					unsigned long addr,
151 					pte_t *ptep, unsigned long clr,
152 					unsigned long set,
153 					int huge)
154 {
155 	unsigned long old_pte;
156 
157 	if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
158 
159 		unsigned long new_pte;
160 
161 		old_pte = __radix_pte_update(ptep, ~0ul, 0);
162 		/*
163 		 * new value of pte
164 		 */
165 		new_pte = (old_pte | set) & ~clr;
166 		radix__flush_tlb_pte_p9_dd1(old_pte, mm, addr);
167 		if (new_pte)
168 			__radix_pte_update(ptep, 0, new_pte);
169 	} else
170 		old_pte = __radix_pte_update(ptep, clr, set);
171 	if (!huge)
172 		assert_pte_locked(mm, addr);
173 
174 	return old_pte;
175 }
176 
177 static inline pte_t radix__ptep_get_and_clear_full(struct mm_struct *mm,
178 						   unsigned long addr,
179 						   pte_t *ptep, int full)
180 {
181 	unsigned long old_pte;
182 
183 	if (full) {
184 		old_pte = pte_val(*ptep);
185 		*ptep = __pte(0);
186 	} else
187 		old_pte = radix__pte_update(mm, addr, ptep, ~0ul, 0, 0);
188 
189 	return __pte(old_pte);
190 }
191 
192 static inline int radix__pte_same(pte_t pte_a, pte_t pte_b)
193 {
194 	return ((pte_raw(pte_a) ^ pte_raw(pte_b)) == 0);
195 }
196 
197 static inline int radix__pte_none(pte_t pte)
198 {
199 	return (pte_val(pte) & ~RADIX_PTE_NONE_MASK) == 0;
200 }
201 
202 static inline void radix__set_pte_at(struct mm_struct *mm, unsigned long addr,
203 				 pte_t *ptep, pte_t pte, int percpu)
204 {
205 	*ptep = pte;
206 
207 	/*
208 	 * The architecture suggests a ptesync after setting the pte, which
209 	 * orders the store that updates the pte with subsequent page table
210 	 * walk accesses which may load the pte. Without this it may be
211 	 * possible for a subsequent access to result in spurious fault.
212 	 *
213 	 * This is not necessary for correctness, because a spurious fault
214 	 * is tolerated by the page fault handler, and this store will
215 	 * eventually be seen. In testing, there was no noticable increase
216 	 * in user faults on POWER9. Avoiding ptesync here is a significant
217 	 * win for things like fork. If a future microarchitecture benefits
218 	 * from ptesync, it should probably go into update_mmu_cache, rather
219 	 * than set_pte_at (which is used to set ptes unrelated to faults).
220 	 *
221 	 * Spurious faults to vmalloc region are not tolerated, so there is
222 	 * a ptesync in flush_cache_vmap.
223 	 */
224 }
225 
226 static inline int radix__pmd_bad(pmd_t pmd)
227 {
228 	return !!(pmd_val(pmd) & RADIX_PMD_BAD_BITS);
229 }
230 
231 static inline int radix__pmd_same(pmd_t pmd_a, pmd_t pmd_b)
232 {
233 	return ((pmd_raw(pmd_a) ^ pmd_raw(pmd_b)) == 0);
234 }
235 
236 static inline int radix__pud_bad(pud_t pud)
237 {
238 	return !!(pud_val(pud) & RADIX_PUD_BAD_BITS);
239 }
240 
241 
242 static inline int radix__pgd_bad(pgd_t pgd)
243 {
244 	return !!(pgd_val(pgd) & RADIX_PGD_BAD_BITS);
245 }
246 
247 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
248 
249 static inline int radix__pmd_trans_huge(pmd_t pmd)
250 {
251 	return (pmd_val(pmd) & (_PAGE_PTE | _PAGE_DEVMAP)) == _PAGE_PTE;
252 }
253 
254 static inline pmd_t radix__pmd_mkhuge(pmd_t pmd)
255 {
256 	if (cpu_has_feature(CPU_FTR_POWER9_DD1))
257 		return __pmd(pmd_val(pmd) | _PAGE_PTE | R_PAGE_LARGE);
258 	return __pmd(pmd_val(pmd) | _PAGE_PTE);
259 }
260 
261 extern unsigned long radix__pmd_hugepage_update(struct mm_struct *mm, unsigned long addr,
262 					  pmd_t *pmdp, unsigned long clr,
263 					  unsigned long set);
264 extern pmd_t radix__pmdp_collapse_flush(struct vm_area_struct *vma,
265 				  unsigned long address, pmd_t *pmdp);
266 extern void radix__pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
267 					pgtable_t pgtable);
268 extern pgtable_t radix__pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
269 extern pmd_t radix__pmdp_huge_get_and_clear(struct mm_struct *mm,
270 				      unsigned long addr, pmd_t *pmdp);
271 extern int radix__has_transparent_hugepage(void);
272 #endif
273 
274 extern int __meminit radix__vmemmap_create_mapping(unsigned long start,
275 					     unsigned long page_size,
276 					     unsigned long phys);
277 extern void radix__vmemmap_remove_mapping(unsigned long start,
278 				    unsigned long page_size);
279 
280 extern int radix__map_kernel_page(unsigned long ea, unsigned long pa,
281 				 pgprot_t flags, unsigned int psz);
282 
283 static inline unsigned long radix__get_tree_size(void)
284 {
285 	unsigned long rts_field;
286 	/*
287 	 * We support 52 bits, hence:
288 	 *  DD1    52-28 = 24, 0b11000
289 	 *  Others 52-31 = 21, 0b10101
290 	 * RTS encoding details
291 	 * bits 0 - 3 of rts -> bits 6 - 8 unsigned long
292 	 * bits 4 - 5 of rts -> bits 62 - 63 of unsigned long
293 	 */
294 	if (cpu_has_feature(CPU_FTR_POWER9_DD1))
295 		rts_field = (0x3UL << 61);
296 	else {
297 		rts_field = (0x5UL << 5); /* 6 - 8 bits */
298 		rts_field |= (0x2UL << 61);
299 	}
300 	return rts_field;
301 }
302 
303 #ifdef CONFIG_MEMORY_HOTPLUG
304 int radix__create_section_mapping(unsigned long start, unsigned long end, int nid);
305 int radix__remove_section_mapping(unsigned long start, unsigned long end);
306 #endif /* CONFIG_MEMORY_HOTPLUG */
307 #endif /* __ASSEMBLY__ */
308 #endif
309