1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_BOOK3S_64_HASH_4K_H
3 #define _ASM_POWERPC_BOOK3S_64_HASH_4K_H
4 
5 #define H_PTE_INDEX_SIZE  9  // size: 8B << 9 = 4KB, maps: 2^9 x   4KB =   2MB
6 #define H_PMD_INDEX_SIZE  7  // size: 8B << 7 = 1KB, maps: 2^7 x   2MB = 256MB
7 #define H_PUD_INDEX_SIZE  9  // size: 8B << 9 = 4KB, maps: 2^9 x 256MB = 128GB
8 #define H_PGD_INDEX_SIZE  9  // size: 8B << 9 = 4KB, maps: 2^9 x 128GB =  64TB
9 
10 /*
11  * Each context is 512TB. But on 4k we restrict our max TASK size to 64TB
12  * Hence also limit max EA bits to 64TB.
13  */
14 #define MAX_EA_BITS_PER_CONTEXT		46
15 
16 #define REGION_SHIFT		(MAX_EA_BITS_PER_CONTEXT - 2)
17 
18 /*
19  * Our page table limit us to 64TB. Hence for the kernel mapping,
20  * each MAP area is limited to 16 TB.
21  * The four map areas are:  linear mapping, vmap, IO and vmemmap
22  */
23 #define H_KERN_MAP_SIZE		(ASM_CONST(1) << REGION_SHIFT)
24 
25 /*
26  * Define the address range of the kernel non-linear virtual area
27  * 16TB
28  */
29 #define H_KERN_VIRT_START	ASM_CONST(0xc000100000000000)
30 
31 #ifndef __ASSEMBLY__
32 #define H_PTE_TABLE_SIZE	(sizeof(pte_t) << H_PTE_INDEX_SIZE)
33 #define H_PMD_TABLE_SIZE	(sizeof(pmd_t) << H_PMD_INDEX_SIZE)
34 #define H_PUD_TABLE_SIZE	(sizeof(pud_t) << H_PUD_INDEX_SIZE)
35 #define H_PGD_TABLE_SIZE	(sizeof(pgd_t) << H_PGD_INDEX_SIZE)
36 
37 #define H_PAGE_F_GIX_SHIFT	53
38 #define H_PAGE_F_SECOND	_RPAGE_RPN44	/* HPTE is in 2ndary HPTEG */
39 #define H_PAGE_F_GIX	(_RPAGE_RPN43 | _RPAGE_RPN42 | _RPAGE_RPN41)
40 #define H_PAGE_BUSY	_RPAGE_RSV1     /* software: PTE & hash are busy */
41 #define H_PAGE_HASHPTE	_RPAGE_RSV2     /* software: PTE & hash are busy */
42 
43 /* PTE flags to conserve for HPTE identification */
44 #define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | \
45 			 H_PAGE_F_SECOND | H_PAGE_F_GIX)
46 /*
47  * Not supported by 4k linux page size
48  */
49 #define H_PAGE_4K_PFN	0x0
50 #define H_PAGE_THP_HUGE 0x0
51 #define H_PAGE_COMBO	0x0
52 
53 /* 8 bytes per each pte entry */
54 #define H_PTE_FRAG_SIZE_SHIFT  (H_PTE_INDEX_SIZE + 3)
55 #define H_PTE_FRAG_NR	(PAGE_SIZE >> H_PTE_FRAG_SIZE_SHIFT)
56 #define H_PMD_FRAG_SIZE_SHIFT  (H_PMD_INDEX_SIZE + 3)
57 #define H_PMD_FRAG_NR	(PAGE_SIZE >> H_PMD_FRAG_SIZE_SHIFT)
58 
59 /* memory key bits, only 8 keys supported */
60 #define H_PTE_PKEY_BIT0	0
61 #define H_PTE_PKEY_BIT1	0
62 #define H_PTE_PKEY_BIT2	_RPAGE_RSV3
63 #define H_PTE_PKEY_BIT3	_RPAGE_RSV4
64 #define H_PTE_PKEY_BIT4	_RPAGE_RSV5
65 
66 /*
67  * On all 4K setups, remap_4k_pfn() equates to remap_pfn_range()
68  */
69 #define remap_4k_pfn(vma, addr, pfn, prot)	\
70 	remap_pfn_range((vma), (addr), (pfn), PAGE_SIZE, (prot))
71 
72 #ifdef CONFIG_HUGETLB_PAGE
73 static inline int hash__hugepd_ok(hugepd_t hpd)
74 {
75 	unsigned long hpdval = hpd_val(hpd);
76 	/*
77 	 * if it is not a pte and have hugepd shift mask
78 	 * set, then it is a hugepd directory pointer
79 	 */
80 	if (!(hpdval & _PAGE_PTE) && (hpdval & _PAGE_PRESENT) &&
81 	    ((hpdval & HUGEPD_SHIFT_MASK) != 0))
82 		return true;
83 	return false;
84 }
85 #endif
86 
87 /*
88  * 4K PTE format is different from 64K PTE format. Saving the hash_slot is just
89  * a matter of returning the PTE bits that need to be modified. On 64K PTE,
90  * things are a little more involved and hence needs many more parameters to
91  * accomplish the same. However we want to abstract this out from the caller by
92  * keeping the prototype consistent across the two formats.
93  */
94 static inline unsigned long pte_set_hidx(pte_t *ptep, real_pte_t rpte,
95 					 unsigned int subpg_index, unsigned long hidx,
96 					 int offset)
97 {
98 	return (hidx << H_PAGE_F_GIX_SHIFT) &
99 		(H_PAGE_F_SECOND | H_PAGE_F_GIX);
100 }
101 
102 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
103 
104 static inline char *get_hpte_slot_array(pmd_t *pmdp)
105 {
106 	BUG();
107 	return NULL;
108 }
109 
110 static inline unsigned int hpte_valid(unsigned char *hpte_slot_array, int index)
111 {
112 	BUG();
113 	return 0;
114 }
115 
116 static inline unsigned int hpte_hash_index(unsigned char *hpte_slot_array,
117 					   int index)
118 {
119 	BUG();
120 	return 0;
121 }
122 
123 static inline void mark_hpte_slot_valid(unsigned char *hpte_slot_array,
124 					unsigned int index, unsigned int hidx)
125 {
126 	BUG();
127 }
128 
129 static inline int hash__pmd_trans_huge(pmd_t pmd)
130 {
131 	return 0;
132 }
133 
134 static inline int hash__pmd_same(pmd_t pmd_a, pmd_t pmd_b)
135 {
136 	BUG();
137 	return 0;
138 }
139 
140 static inline pmd_t hash__pmd_mkhuge(pmd_t pmd)
141 {
142 	BUG();
143 	return pmd;
144 }
145 
146 extern unsigned long hash__pmd_hugepage_update(struct mm_struct *mm,
147 					   unsigned long addr, pmd_t *pmdp,
148 					   unsigned long clr, unsigned long set);
149 extern pmd_t hash__pmdp_collapse_flush(struct vm_area_struct *vma,
150 				   unsigned long address, pmd_t *pmdp);
151 extern void hash__pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
152 					 pgtable_t pgtable);
153 extern pgtable_t hash__pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
154 extern pmd_t hash__pmdp_huge_get_and_clear(struct mm_struct *mm,
155 				       unsigned long addr, pmd_t *pmdp);
156 extern int hash__has_transparent_hugepage(void);
157 #endif
158 
159 #endif /* !__ASSEMBLY__ */
160 
161 #endif /* _ASM_POWERPC_BOOK3S_64_HASH_4K_H */
162