1 /* $Id: memory.c,v 1.15 2000/01/29 01:09:12 anton Exp $
2  * memory.c: Prom routine for acquiring various bits of information
3  *           about RAM on the machine, both virtual and physical.
4  *
5  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6  * Copyright (C) 1997 Michael A. Griffith (grif@acm.org)
7  */
8 
9 #include <linux/config.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 
13 #include <asm/openprom.h>
14 #include <asm/sun4prom.h>
15 #include <asm/oplib.h>
16 
17 /* This routine, for consistency, returns the ram parameters in the
18  * V0 prom memory descriptor format.  I choose this format because I
19  * think it was the easiest to work with.  I feel the religious
20  * arguments now... ;)  Also, I return the linked lists sorted to
21  * prevent paging_init() upset stomach as I have not yet written
22  * the pepto-bismol kernel module yet.
23  */
24 
25 struct linux_prom_registers prom_reg_memlist[64];
26 struct linux_prom_registers prom_reg_tmp[64];
27 
28 struct linux_mlist_v0 prom_phys_total[64];
29 struct linux_mlist_v0 prom_prom_taken[64];
30 struct linux_mlist_v0 prom_phys_avail[64];
31 
32 struct linux_mlist_v0 *prom_ptot_ptr = prom_phys_total;
33 struct linux_mlist_v0 *prom_ptak_ptr = prom_prom_taken;
34 struct linux_mlist_v0 *prom_pavl_ptr = prom_phys_avail;
35 
36 struct linux_mem_v0 prom_memlist;
37 
38 
39 /* Internal Prom library routine to sort a linux_mlist_v0 memory
40  * list.  Used below in initialization.
41  */
42 static void __init
prom_sortmemlist(struct linux_mlist_v0 * thislist)43 prom_sortmemlist(struct linux_mlist_v0 *thislist)
44 {
45 	int swapi = 0;
46 	int i, mitr, tmpsize;
47 	char *tmpaddr;
48 	char *lowest;
49 
50 	for(i=0; thislist[i].theres_more != 0; i++) {
51 		lowest = thislist[i].start_adr;
52 		for(mitr = i+1; thislist[mitr-1].theres_more != 0; mitr++)
53 			if(thislist[mitr].start_adr < lowest) {
54 				lowest = thislist[mitr].start_adr;
55 				swapi = mitr;
56 			}
57 		if(lowest == thislist[i].start_adr) continue;
58 		tmpaddr = thislist[swapi].start_adr;
59 		tmpsize = thislist[swapi].num_bytes;
60 		for(mitr = swapi; mitr > i; mitr--) {
61 			thislist[mitr].start_adr = thislist[mitr-1].start_adr;
62 			thislist[mitr].num_bytes = thislist[mitr-1].num_bytes;
63 		}
64 		thislist[i].start_adr = tmpaddr;
65 		thislist[i].num_bytes = tmpsize;
66 	}
67 
68 	return;
69 }
70 
71 /* Initialize the memory lists based upon the prom version. */
prom_meminit(void)72 void __init prom_meminit(void)
73 {
74 	int node = 0;
75 	unsigned int iter, num_regs;
76 	struct linux_mlist_v0 *mptr;  /* ptr for traversal */
77 
78 	switch(prom_vers) {
79 	case PROM_V0:
80 		/* Nice, kind of easier to do in this case. */
81 		/* First, the total physical descriptors. */
82 		for(mptr = (*(romvec->pv_v0mem.v0_totphys)), iter=0;
83 		    mptr; mptr=mptr->theres_more, iter++) {
84 			prom_phys_total[iter].start_adr = mptr->start_adr;
85 			prom_phys_total[iter].num_bytes = mptr->num_bytes;
86 			prom_phys_total[iter].theres_more = &prom_phys_total[iter+1];
87 		}
88 		prom_phys_total[iter-1].theres_more = 0x0;
89 		/* Second, the total prom taken descriptors. */
90 		for(mptr = (*(romvec->pv_v0mem.v0_prommap)), iter=0;
91 		    mptr; mptr=mptr->theres_more, iter++) {
92 			prom_prom_taken[iter].start_adr = mptr->start_adr;
93 			prom_prom_taken[iter].num_bytes = mptr->num_bytes;
94 			prom_prom_taken[iter].theres_more = &prom_prom_taken[iter+1];
95 		}
96 		prom_prom_taken[iter-1].theres_more = 0x0;
97 		/* Last, the available physical descriptors. */
98 		for(mptr = (*(romvec->pv_v0mem.v0_available)), iter=0;
99 		    mptr; mptr=mptr->theres_more, iter++) {
100 			prom_phys_avail[iter].start_adr = mptr->start_adr;
101 			prom_phys_avail[iter].num_bytes = mptr->num_bytes;
102 			prom_phys_avail[iter].theres_more = &prom_phys_avail[iter+1];
103 		}
104 		prom_phys_avail[iter-1].theres_more = 0x0;
105 		/* Sort all the lists. */
106 		prom_sortmemlist(prom_phys_total);
107 		prom_sortmemlist(prom_prom_taken);
108 		prom_sortmemlist(prom_phys_avail);
109 		break;
110 	case PROM_V2:
111 	case PROM_V3:
112 		/* Grrr, have to traverse the prom device tree ;( */
113 		node = prom_getchild(prom_root_node);
114 		node = prom_searchsiblings(node, "memory");
115 		num_regs = prom_getproperty(node, "available",
116 					    (char *) prom_reg_memlist,
117 					    sizeof(prom_reg_memlist));
118 		num_regs = (num_regs/sizeof(struct linux_prom_registers));
119 		for(iter=0; iter<num_regs; iter++) {
120 			prom_phys_avail[iter].start_adr =
121 				(char *) prom_reg_memlist[iter].phys_addr;
122 			prom_phys_avail[iter].num_bytes =
123 				(unsigned long) prom_reg_memlist[iter].reg_size;
124 			prom_phys_avail[iter].theres_more =
125 				&prom_phys_avail[iter+1];
126 		}
127 		prom_phys_avail[iter-1].theres_more = 0x0;
128 
129 		num_regs = prom_getproperty(node, "reg",
130 					    (char *) prom_reg_memlist,
131 					    sizeof(prom_reg_memlist));
132 		num_regs = (num_regs/sizeof(struct linux_prom_registers));
133 		for(iter=0; iter<num_regs; iter++) {
134 			prom_phys_total[iter].start_adr =
135 				(char *) prom_reg_memlist[iter].phys_addr;
136 			prom_phys_total[iter].num_bytes =
137 				(unsigned long) prom_reg_memlist[iter].reg_size;
138 			prom_phys_total[iter].theres_more =
139 				&prom_phys_total[iter+1];
140 		}
141 		prom_phys_total[iter-1].theres_more = 0x0;
142 
143 		node = prom_getchild(prom_root_node);
144 		node = prom_searchsiblings(node, "virtual-memory");
145 		num_regs = prom_getproperty(node, "available",
146 					    (char *) prom_reg_memlist,
147 					    sizeof(prom_reg_memlist));
148 		num_regs = (num_regs/sizeof(struct linux_prom_registers));
149 
150 		/* Convert available virtual areas to taken virtual
151 		 * areas.  First sort, then convert.
152 		 */
153 		for(iter=0; iter<num_regs; iter++) {
154 			prom_prom_taken[iter].start_adr =
155 				(char *) prom_reg_memlist[iter].phys_addr;
156 			prom_prom_taken[iter].num_bytes =
157 				(unsigned long) prom_reg_memlist[iter].reg_size;
158 			prom_prom_taken[iter].theres_more =
159 				&prom_prom_taken[iter+1];
160 		}
161 		prom_prom_taken[iter-1].theres_more = 0x0;
162 
163 		prom_sortmemlist(prom_prom_taken);
164 
165 		/* Finally, convert. */
166 		for(iter=0; iter<num_regs; iter++) {
167 			prom_prom_taken[iter].start_adr =
168 				prom_prom_taken[iter].start_adr +
169 					prom_prom_taken[iter].num_bytes;
170 			prom_prom_taken[iter].num_bytes =
171 				prom_prom_taken[iter+1].start_adr -
172 					prom_prom_taken[iter].start_adr;
173 		}
174 		prom_prom_taken[iter-1].num_bytes =
175 			0xffffffff - (unsigned long) prom_prom_taken[iter-1].start_adr;
176 
177 		/* Sort the other two lists. */
178 		prom_sortmemlist(prom_phys_total);
179 		prom_sortmemlist(prom_phys_avail);
180 		break;
181 
182 	case PROM_SUN4:
183 #ifdef CONFIG_SUN4
184 		/* how simple :) */
185 		prom_phys_total[0].start_adr = 0x0;
186 		prom_phys_total[0].num_bytes = *(sun4_romvec->memorysize);
187 		prom_phys_total[0].theres_more = 0x0;
188 		prom_prom_taken[0].start_adr = 0x0;
189 		prom_prom_taken[0].num_bytes = 0x0;
190 		prom_prom_taken[0].theres_more = 0x0;
191 		prom_phys_avail[0].start_adr = 0x0;
192 		prom_phys_avail[0].num_bytes = *(sun4_romvec->memoryavail);
193 		prom_phys_avail[0].theres_more = 0x0;
194 #endif
195 		break;
196 
197 	default:
198 		break;
199 	};
200 
201 	/* Link all the lists into the top-level descriptor. */
202 	prom_memlist.v0_totphys=&prom_ptot_ptr;
203 	prom_memlist.v0_prommap=&prom_ptak_ptr;
204 	prom_memlist.v0_available=&prom_pavl_ptr;
205 
206 	return;
207 }
208 
209 /* This returns a pointer to our libraries internal v0 format
210  * memory descriptor.
211  */
212 struct linux_mem_v0 *
prom_meminfo(void)213 prom_meminfo(void)
214 {
215 	return &prom_memlist;
216 }
217