xref: /openbmc/linux/arch/powerpc/boot/of.c (revision cfbb9be8)
1 /*
2  * Copyright (C) Paul Mackerras 1997.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  */
9 #include <stdarg.h>
10 #include <stddef.h>
11 #include "types.h"
12 #include "elf.h"
13 #include "string.h"
14 #include "stdio.h"
15 #include "page.h"
16 #include "ops.h"
17 
18 #include "of.h"
19 
20 /* Value picked to match that used by yaboot */
21 #define PROG_START	0x01400000	/* only used on 64-bit systems */
22 #define RAM_END		(512<<20)	/* Fixme: use OF */
23 #define	ONE_MB		0x100000
24 
25 
26 
27 static unsigned long claim_base;
28 
29 void epapr_platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
30 			 unsigned long r6, unsigned long r7);
31 
32 static void *of_try_claim(unsigned long size)
33 {
34 	unsigned long addr = 0;
35 
36 	if (claim_base == 0)
37 		claim_base = _ALIGN_UP((unsigned long)_end, ONE_MB);
38 
39 	for(; claim_base < RAM_END; claim_base += ONE_MB) {
40 #ifdef DEBUG
41 		printf("    trying: 0x%08lx\n\r", claim_base);
42 #endif
43 		addr = (unsigned long) of_claim(claim_base, size, 0);
44 		if (addr != PROM_ERROR)
45 			break;
46 	}
47 	if (addr == 0)
48 		return NULL;
49 	claim_base = PAGE_ALIGN(claim_base + size);
50 	return (void *)addr;
51 }
52 
53 static void of_image_hdr(const void *hdr)
54 {
55 	const Elf64_Ehdr *elf64 = hdr;
56 
57 	if (elf64->e_ident[EI_CLASS] == ELFCLASS64) {
58 		/*
59 		 * Maintain a "magic" minimum address. This keeps some older
60 		 * firmware platforms running.
61 		 */
62 		if (claim_base < PROG_START)
63 			claim_base = PROG_START;
64 	}
65 }
66 
67 static void of_platform_init(unsigned long a1, unsigned long a2, void *promptr)
68 {
69 	platform_ops.image_hdr = of_image_hdr;
70 	platform_ops.malloc = of_try_claim;
71 	platform_ops.exit = of_exit;
72 	platform_ops.vmlinux_alloc = of_vmlinux_alloc;
73 
74 	dt_ops.finddevice = of_finddevice;
75 	dt_ops.getprop = of_getprop;
76 	dt_ops.setprop = of_setprop;
77 
78 	of_console_init();
79 
80 	of_init(promptr);
81 	loader_info.promptr = promptr;
82 	if (a1 && a2 && a2 != 0xdeadbeef) {
83 		loader_info.initrd_addr = a1;
84 		loader_info.initrd_size = a2;
85 	}
86 }
87 
88 void platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
89 		   unsigned long r6, unsigned long r7)
90 {
91 	/* Detect OF vs. ePAPR boot */
92 	if (r5)
93 		of_platform_init(r3, r4, (void *)r5);
94 	else
95 		epapr_platform_init(r3, r4, r5, r6, r7);
96 }
97 
98