xref: /openbmc/linux/arch/mips/fw/arc/memory.c (revision 94bd83e4)
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 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