1/* $Id: memory.c,v 1.1.1.1 2007/08/03 18:52:18 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/kernel.h>
10#include <linux/init.h>
11
12#include <asm/openprom.h>
13#include <asm/sun4prom.h>
14#include <asm/oplib.h>
15
16/* This routine, for consistency, returns the ram parameters in the
17 * V0 prom memory descriptor format.  I choose this format because I
18 * think it was the easiest to work with.  I feel the religious
19 * arguments now... ;)  Also, I return the linked lists sorted to
20 * prevent paging_init() upset stomach as I have not yet written
21 * the pepto-bismol kernel module yet.
22 */
23
24struct linux_prom_registers prom_reg_memlist[64];
25struct linux_prom_registers prom_reg_tmp[64];
26
27struct linux_mlist_v0 prom_phys_total[64];
28struct linux_mlist_v0 prom_prom_taken[64];
29struct linux_mlist_v0 prom_phys_avail[64];
30
31struct linux_mlist_v0 *prom_ptot_ptr = prom_phys_total;
32struct linux_mlist_v0 *prom_ptak_ptr = prom_prom_taken;
33struct linux_mlist_v0 *prom_pavl_ptr = prom_phys_avail;
34
35struct linux_mem_v0 prom_memlist;
36
37
38/* Internal Prom library routine to sort a linux_mlist_v0 memory
39 * list.  Used below in initialization.
40 */
41static void __init
42prom_sortmemlist(struct linux_mlist_v0 *thislist)
43{
44	int swapi = 0;
45	int i, mitr, tmpsize;
46	char *tmpaddr;
47	char *lowest;
48
49	for(i=0; thislist[i].theres_more; i++) {
50		lowest = thislist[i].start_adr;
51		for(mitr = i+1; thislist[mitr-1].theres_more; mitr++)
52			if(thislist[mitr].start_adr < lowest) {
53				lowest = thislist[mitr].start_adr;
54				swapi = mitr;
55			}
56		if(lowest == thislist[i].start_adr) continue;
57		tmpaddr = thislist[swapi].start_adr;
58		tmpsize = thislist[swapi].num_bytes;
59		for(mitr = swapi; mitr > i; mitr--) {
60			thislist[mitr].start_adr = thislist[mitr-1].start_adr;
61			thislist[mitr].num_bytes = thislist[mitr-1].num_bytes;
62		}
63		thislist[i].start_adr = tmpaddr;
64		thislist[i].num_bytes = tmpsize;
65	}
66
67	return;
68}
69
70/* Initialize the memory lists based upon the prom version. */
71void __init prom_meminit(void)
72{
73	int node = 0;
74	unsigned int iter, num_regs;
75	struct linux_mlist_v0 *mptr;  /* ptr for traversal */
76
77	switch(prom_vers) {
78	case PROM_V0:
79		/* Nice, kind of easier to do in this case. */
80		/* First, the total physical descriptors. */
81		for(mptr = (*(romvec->pv_v0mem.v0_totphys)), iter=0;
82		    mptr; mptr=mptr->theres_more, iter++) {
83			prom_phys_total[iter].start_adr = mptr->start_adr;
84			prom_phys_total[iter].num_bytes = mptr->num_bytes;
85			prom_phys_total[iter].theres_more = &prom_phys_total[iter+1];
86		}
87		prom_phys_total[iter-1].theres_more = NULL;
88		/* Second, the total prom taken descriptors. */
89		for(mptr = (*(romvec->pv_v0mem.v0_prommap)), iter=0;
90		    mptr; mptr=mptr->theres_more, iter++) {
91			prom_prom_taken[iter].start_adr = mptr->start_adr;
92			prom_prom_taken[iter].num_bytes = mptr->num_bytes;
93			prom_prom_taken[iter].theres_more = &prom_prom_taken[iter+1];
94		}
95		prom_prom_taken[iter-1].theres_more = NULL;
96		/* Last, the available physical descriptors. */
97		for(mptr = (*(romvec->pv_v0mem.v0_available)), iter=0;
98		    mptr; mptr=mptr->theres_more, iter++) {
99			prom_phys_avail[iter].start_adr = mptr->start_adr;
100			prom_phys_avail[iter].num_bytes = mptr->num_bytes;
101			prom_phys_avail[iter].theres_more = &prom_phys_avail[iter+1];
102		}
103		prom_phys_avail[iter-1].theres_more = NULL;
104		/* Sort all the lists. */
105		prom_sortmemlist(prom_phys_total);
106		prom_sortmemlist(prom_prom_taken);
107		prom_sortmemlist(prom_phys_avail);
108		break;
109	case PROM_V2:
110	case PROM_V3:
111		/* Grrr, have to traverse the prom device tree ;( */
112		node = prom_getchild(prom_root_node);
113		node = prom_searchsiblings(node, "memory");
114		num_regs = prom_getproperty(node, "available",
115					    (char *) prom_reg_memlist,
116					    sizeof(prom_reg_memlist));
117		num_regs = (num_regs/sizeof(struct linux_prom_registers));
118		for(iter=0; iter<num_regs; iter++) {
119			prom_phys_avail[iter].start_adr =
120				(char *) prom_reg_memlist[iter].phys_addr;
121			prom_phys_avail[iter].num_bytes =
122				(unsigned long) prom_reg_memlist[iter].reg_size;
123			prom_phys_avail[iter].theres_more =
124				&prom_phys_avail[iter+1];
125		}
126		prom_phys_avail[iter-1].theres_more = NULL;
127
128		num_regs = prom_getproperty(node, "reg",
129					    (char *) prom_reg_memlist,
130					    sizeof(prom_reg_memlist));
131		num_regs = (num_regs/sizeof(struct linux_prom_registers));
132		for(iter=0; iter<num_regs; iter++) {
133			prom_phys_total[iter].start_adr =
134				(char *) prom_reg_memlist[iter].phys_addr;
135			prom_phys_total[iter].num_bytes =
136				(unsigned long) prom_reg_memlist[iter].reg_size;
137			prom_phys_total[iter].theres_more =
138				&prom_phys_total[iter+1];
139		}
140		prom_phys_total[iter-1].theres_more = NULL;
141
142		node = prom_getchild(prom_root_node);
143		node = prom_searchsiblings(node, "virtual-memory");
144		num_regs = prom_getproperty(node, "available",
145					    (char *) prom_reg_memlist,
146					    sizeof(prom_reg_memlist));
147		num_regs = (num_regs/sizeof(struct linux_prom_registers));
148
149		/* Convert available virtual areas to taken virtual
150		 * areas.  First sort, then convert.
151		 */
152		for(iter=0; iter<num_regs; iter++) {
153			prom_prom_taken[iter].start_adr =
154				(char *) prom_reg_memlist[iter].phys_addr;
155			prom_prom_taken[iter].num_bytes =
156				(unsigned long) prom_reg_memlist[iter].reg_size;
157			prom_prom_taken[iter].theres_more =
158				&prom_prom_taken[iter+1];
159		}
160		prom_prom_taken[iter-1].theres_more = NULL;
161
162		prom_sortmemlist(prom_prom_taken);
163
164		/* Finally, convert. */
165		for(iter=0; iter<num_regs; iter++) {
166			prom_prom_taken[iter].start_adr =
167				prom_prom_taken[iter].start_adr +
168					prom_prom_taken[iter].num_bytes;
169			prom_prom_taken[iter].num_bytes =
170				prom_prom_taken[iter+1].start_adr -
171					prom_prom_taken[iter].start_adr;
172		}
173		prom_prom_taken[iter-1].num_bytes =
174			0xffffffff - (unsigned long) prom_prom_taken[iter-1].start_adr;
175
176		/* Sort the other two lists. */
177		prom_sortmemlist(prom_phys_total);
178		prom_sortmemlist(prom_phys_avail);
179		break;
180
181	case PROM_SUN4:
182#ifdef CONFIG_SUN4
183		/* how simple :) */
184		prom_phys_total[0].start_adr = NULL;
185		prom_phys_total[0].num_bytes = *(sun4_romvec->memorysize);
186		prom_phys_total[0].theres_more = NULL;
187		prom_prom_taken[0].start_adr = NULL;
188		prom_prom_taken[0].num_bytes = 0x0;
189		prom_prom_taken[0].theres_more = NULL;
190		prom_phys_avail[0].start_adr = NULL;
191		prom_phys_avail[0].num_bytes = *(sun4_romvec->memoryavail);
192		prom_phys_avail[0].theres_more = NULL;
193#endif
194		break;
195
196	default:
197		break;
198	};
199
200	/* Link all the lists into the top-level descriptor. */
201	prom_memlist.v0_totphys=&prom_ptot_ptr;
202	prom_memlist.v0_prommap=&prom_ptak_ptr;
203	prom_memlist.v0_available=&prom_pavl_ptr;
204
205	return;
206}
207
208/* This returns a pointer to our libraries internal v0 format
209 * memory descriptor.
210 */
211struct linux_mem_v0 *
212prom_meminfo(void)
213{
214	return &prom_memlist;
215}
216