1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * memory.c: PROM library functions for acquiring/using memory descriptors
4 * given to us from the ARCS firmware.
5 *
6 * Copyright (C) 1996 by David S. Miller
7 * Copyright (C) 1999, 2000, 2001 by Ralf Baechle
8 * Copyright (C) 1999, 2000 by Silicon Graphics, Inc.
9 *
10 * PROM library functions for acquiring/using memory descriptors given to us
11 * from the ARCS firmware. This is only used when CONFIG_ARC_MEMORY is set
12 * because on some machines like SGI IP27 the ARC memory configuration data
13 * completely bogus and alternate easier to use mechanisms are available.
14 */
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/types.h>
18 #include <linux/sched.h>
19 #include <linux/mm.h>
20 #include <linux/memblock.h>
21 #include <linux/swap.h>
22
23 #include <asm/sgialib.h>
24 #include <asm/page.h>
25 #include <asm/bootinfo.h>
26
27 #undef DEBUG
28
29 #define MAX_PROM_MEM 5
30 static phys_addr_t prom_mem_base[MAX_PROM_MEM] __initdata;
31 static phys_addr_t prom_mem_size[MAX_PROM_MEM] __initdata;
32 static unsigned int nr_prom_mem __initdata;
33
34 /*
35 * For ARC firmware memory functions the unit of measuring memory is always
36 * a 4k page of memory
37 */
38 #define ARC_PAGE_SHIFT 12
39
ArcGetMemoryDescriptor(struct linux_mdesc * Current)40 static struct linux_mdesc * __init ArcGetMemoryDescriptor(struct linux_mdesc *Current)
41 {
42 return (struct linux_mdesc *) ARC_CALL1(get_mdesc, Current);
43 }
44
45 #ifdef DEBUG /* convenient for debugging */
46 static char *arcs_mtypes[8] = {
47 "Exception Block",
48 "ARCS Romvec Page",
49 "Free/Contig RAM",
50 "Generic Free RAM",
51 "Bad Memory",
52 "Standalone Program Pages",
53 "ARCS Temp Storage Area",
54 "ARCS Permanent Storage Area"
55 };
56
57 static char *arc_mtypes[8] = {
58 "Exception Block",
59 "SystemParameterBlock",
60 "FreeMemory",
61 "Bad Memory",
62 "LoadedProgram",
63 "FirmwareTemporary",
64 "FirmwarePermanent",
65 "FreeContiguous"
66 };
67 #define mtypes(a) (prom_flags & PROM_FLAG_ARCS) ? arcs_mtypes[a.arcs] \
68 : arc_mtypes[a.arc]
69 #endif
70
71 enum {
72 mem_free, mem_prom_used, mem_reserved
73 };
74
memtype_classify_arcs(union linux_memtypes type)75 static inline int memtype_classify_arcs(union linux_memtypes type)
76 {
77 switch (type.arcs) {
78 case arcs_fcontig:
79 case arcs_free:
80 return mem_free;
81 case arcs_atmp:
82 return mem_prom_used;
83 case arcs_eblock:
84 case arcs_rvpage:
85 case arcs_bmem:
86 case arcs_prog:
87 case arcs_aperm:
88 return mem_reserved;
89 default:
90 BUG();
91 }
92 while(1); /* Nuke warning. */
93 }
94
memtype_classify_arc(union linux_memtypes type)95 static inline int memtype_classify_arc(union linux_memtypes type)
96 {
97 switch (type.arc) {
98 case arc_free:
99 case arc_fcontig:
100 return mem_free;
101 case arc_atmp:
102 return mem_prom_used;
103 case arc_eblock:
104 case arc_rvpage:
105 case arc_bmem:
106 case arc_prog:
107 case arc_aperm:
108 return mem_reserved;
109 default:
110 BUG();
111 }
112 while(1); /* Nuke warning. */
113 }
114
prom_memtype_classify(union linux_memtypes type)115 static int __init prom_memtype_classify(union linux_memtypes type)
116 {
117 if (prom_flags & PROM_FLAG_ARCS) /* SGI is ``different'' ... */
118 return memtype_classify_arcs(type);
119
120 return memtype_classify_arc(type);
121 }
122
prom_meminit(void)123 void __weak __init prom_meminit(void)
124 {
125 struct linux_mdesc *p;
126
127 #ifdef DEBUG
128 int i = 0;
129
130 printk("ARCS MEMORY DESCRIPTOR dump:\n");
131 p = ArcGetMemoryDescriptor(PROM_NULL_MDESC);
132 while(p) {
133 printk("[%d,%p]: base<%08lx> pages<%08lx> type<%s>\n",
134 i, p, p->base, p->pages, mtypes(p->type));
135 p = ArcGetMemoryDescriptor(p);
136 i++;
137 }
138 #endif
139
140 nr_prom_mem = 0;
141 p = PROM_NULL_MDESC;
142 while ((p = ArcGetMemoryDescriptor(p))) {
143 unsigned long base, size;
144 long type;
145
146 base = p->base << ARC_PAGE_SHIFT;
147 size = p->pages << ARC_PAGE_SHIFT;
148 type = prom_memtype_classify(p->type);
149
150 /* ignore mirrored RAM on IP28/IP30 */
151 if (base < PHYS_OFFSET)
152 continue;
153
154 memblock_add(base, size);
155
156 if (type == mem_reserved)
157 memblock_reserve(base, size);
158
159 if (type == mem_prom_used) {
160 memblock_reserve(base, size);
161 if (nr_prom_mem >= 5) {
162 pr_err("Too many ROM DATA regions");
163 continue;
164 }
165 prom_mem_base[nr_prom_mem] = base;
166 prom_mem_size[nr_prom_mem] = size;
167 nr_prom_mem++;
168 }
169 }
170 }
171
prom_cleanup(void)172 void __weak __init prom_cleanup(void)
173 {
174 }
175
prom_free_prom_memory(void)176 void __init prom_free_prom_memory(void)
177 {
178 int i;
179
180 if (prom_flags & PROM_FLAG_DONT_FREE_TEMP)
181 return;
182
183 for (i = 0; i < nr_prom_mem; i++) {
184 free_init_pages("prom memory",
185 prom_mem_base[i], prom_mem_base[i] + prom_mem_size[i]);
186 }
187 /*
188 * at this point it isn't safe to call PROM functions
189 * give platforms a way to do PROM cleanups
190 */
191 prom_cleanup();
192 }
193