1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_S390_MEM_DETECT_H
3 #define _ASM_S390_MEM_DETECT_H
4
5 #include <linux/types.h>
6 #include <asm/page.h>
7
8 enum physmem_info_source {
9 MEM_DETECT_NONE = 0,
10 MEM_DETECT_SCLP_STOR_INFO,
11 MEM_DETECT_DIAG260,
12 MEM_DETECT_SCLP_READ_INFO,
13 MEM_DETECT_BIN_SEARCH
14 };
15
16 struct physmem_range {
17 u64 start;
18 u64 end;
19 };
20
21 enum reserved_range_type {
22 RR_DECOMPRESSOR,
23 RR_INITRD,
24 RR_VMLINUX,
25 RR_AMODE31,
26 RR_IPLREPORT,
27 RR_CERT_COMP_LIST,
28 RR_MEM_DETECT_EXTENDED,
29 RR_VMEM,
30 RR_MAX
31 };
32
33 struct reserved_range {
34 unsigned long start;
35 unsigned long end;
36 struct reserved_range *chain;
37 };
38
39 /*
40 * Storage element id is defined as 1 byte (up to 256 storage elements).
41 * In practise only storage element id 0 and 1 are used).
42 * According to architecture one storage element could have as much as
43 * 1020 subincrements. 255 physmem_ranges are embedded in physmem_info.
44 * If more physmem_ranges are required, a block of memory from already
45 * known physmem_range is taken (online_extended points to it).
46 */
47 #define MEM_INLINED_ENTRIES 255 /* (PAGE_SIZE - 16) / 16 */
48
49 struct physmem_info {
50 u32 range_count;
51 u8 info_source;
52 unsigned long usable;
53 struct reserved_range reserved[RR_MAX];
54 struct physmem_range online[MEM_INLINED_ENTRIES];
55 struct physmem_range *online_extended;
56 };
57
58 extern struct physmem_info physmem_info;
59
60 void add_physmem_online_range(u64 start, u64 end);
61
62 static inline int __get_physmem_range(u32 n, unsigned long *start,
63 unsigned long *end, bool respect_usable_limit)
64 {
65 if (n >= physmem_info.range_count) {
66 *start = 0;
67 *end = 0;
68 return -1;
69 }
70
71 if (n < MEM_INLINED_ENTRIES) {
72 *start = (unsigned long)physmem_info.online[n].start;
73 *end = (unsigned long)physmem_info.online[n].end;
74 } else {
75 *start = (unsigned long)physmem_info.online_extended[n - MEM_INLINED_ENTRIES].start;
76 *end = (unsigned long)physmem_info.online_extended[n - MEM_INLINED_ENTRIES].end;
77 }
78
79 if (respect_usable_limit && physmem_info.usable) {
80 if (*start >= physmem_info.usable)
81 return -1;
82 if (*end > physmem_info.usable)
83 *end = physmem_info.usable;
84 }
85 return 0;
86 }
87
88 /**
89 * for_each_physmem_usable_range - early online memory range iterator
90 * @i: an integer used as loop variable
91 * @p_start: ptr to unsigned long for start address of the range
92 * @p_end: ptr to unsigned long for end address of the range
93 *
94 * Walks over detected online memory ranges below usable limit.
95 */
96 #define for_each_physmem_usable_range(i, p_start, p_end) \
97 for (i = 0; !__get_physmem_range(i, p_start, p_end, true); i++)
98
99 /* Walks over all detected online memory ranges disregarding usable limit. */
100 #define for_each_physmem_online_range(i, p_start, p_end) \
101 for (i = 0; !__get_physmem_range(i, p_start, p_end, false); i++)
102
103 static inline const char *get_physmem_info_source(void)
104 {
105 switch (physmem_info.info_source) {
106 case MEM_DETECT_SCLP_STOR_INFO:
107 return "sclp storage info";
108 case MEM_DETECT_DIAG260:
109 return "diag260";
110 case MEM_DETECT_SCLP_READ_INFO:
111 return "sclp read info";
112 case MEM_DETECT_BIN_SEARCH:
113 return "binary search";
114 }
115 return "none";
116 }
117
118 #define RR_TYPE_NAME(t) case RR_ ## t: return #t
119 static inline const char *get_rr_type_name(enum reserved_range_type t)
120 {
121 switch (t) {
122 RR_TYPE_NAME(DECOMPRESSOR);
123 RR_TYPE_NAME(INITRD);
124 RR_TYPE_NAME(VMLINUX);
125 RR_TYPE_NAME(AMODE31);
126 RR_TYPE_NAME(IPLREPORT);
127 RR_TYPE_NAME(CERT_COMP_LIST);
128 RR_TYPE_NAME(MEM_DETECT_EXTENDED);
129 RR_TYPE_NAME(VMEM);
130 default:
131 return "UNKNOWN";
132 }
133 }
134
135 #define for_each_physmem_reserved_type_range(t, range, p_start, p_end) \
136 for (range = &physmem_info.reserved[t], *p_start = range->start, *p_end = range->end; \
137 range && range->end; range = range->chain ? __va(range->chain) : NULL, \
138 *p_start = range ? range->start : 0, *p_end = range ? range->end : 0)
139
140 static inline struct reserved_range *__physmem_reserved_next(enum reserved_range_type *t,
141 struct reserved_range *range)
142 {
143 if (!range) {
144 range = &physmem_info.reserved[*t];
145 if (range->end)
146 return range;
147 }
148 if (range->chain)
149 return __va(range->chain);
150 while (++*t < RR_MAX) {
151 range = &physmem_info.reserved[*t];
152 if (range->end)
153 return range;
154 }
155 return NULL;
156 }
157
158 #define for_each_physmem_reserved_range(t, range, p_start, p_end) \
159 for (t = 0, range = __physmem_reserved_next(&t, NULL), \
160 *p_start = range ? range->start : 0, *p_end = range ? range->end : 0; \
161 range; range = __physmem_reserved_next(&t, range), \
162 *p_start = range ? range->start : 0, *p_end = range ? range->end : 0)
163
164 static inline unsigned long get_physmem_reserved(enum reserved_range_type type,
165 unsigned long *addr, unsigned long *size)
166 {
167 *addr = physmem_info.reserved[type].start;
168 *size = physmem_info.reserved[type].end - physmem_info.reserved[type].start;
169 return *size;
170 }
171
172 #define AMODE31_START (physmem_info.reserved[RR_AMODE31].start)
173 #define AMODE31_END (physmem_info.reserved[RR_AMODE31].end)
174
175 #endif
176
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