xref: /openbmc/linux/arch/powerpc/boot/of.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) Paul Mackerras 1997.
4  */
5 #include <stdarg.h>
6 #include <stddef.h>
7 #include "types.h"
8 #include "elf.h"
9 #include "string.h"
10 #include "stdio.h"
11 #include "page.h"
12 #include "ops.h"
13 
14 #include "of.h"
15 
16 /* Value picked to match that used by yaboot */
17 #define PROG_START	0x01400000	/* only used on 64-bit systems */
18 #define RAM_END		(512<<20)	/* Fixme: use OF */
19 #define	ONE_MB		0x100000
20 
21 
22 
23 static unsigned long claim_base;
24 
25 void epapr_platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
26 			 unsigned long r6, unsigned long r7);
27 
28 static void *of_try_claim(unsigned long size)
29 {
30 	unsigned long addr = 0;
31 
32 	if (claim_base == 0)
33 		claim_base = _ALIGN_UP((unsigned long)_end, ONE_MB);
34 
35 	for(; claim_base < RAM_END; claim_base += ONE_MB) {
36 #ifdef DEBUG
37 		printf("    trying: 0x%08lx\n\r", claim_base);
38 #endif
39 		addr = (unsigned long) of_claim(claim_base, size, 0);
40 		if (addr != PROM_ERROR)
41 			break;
42 	}
43 	if (addr == 0)
44 		return NULL;
45 	claim_base = PAGE_ALIGN(claim_base + size);
46 	return (void *)addr;
47 }
48 
49 static void of_image_hdr(const void *hdr)
50 {
51 	const Elf64_Ehdr *elf64 = hdr;
52 
53 	if (elf64->e_ident[EI_CLASS] == ELFCLASS64) {
54 		/*
55 		 * Maintain a "magic" minimum address. This keeps some older
56 		 * firmware platforms running.
57 		 */
58 		if (claim_base < PROG_START)
59 			claim_base = PROG_START;
60 	}
61 }
62 
63 static void of_platform_init(unsigned long a1, unsigned long a2, void *promptr)
64 {
65 	platform_ops.image_hdr = of_image_hdr;
66 	platform_ops.malloc = of_try_claim;
67 	platform_ops.exit = of_exit;
68 	platform_ops.vmlinux_alloc = of_vmlinux_alloc;
69 
70 	dt_ops.finddevice = of_finddevice;
71 	dt_ops.getprop = of_getprop;
72 	dt_ops.setprop = of_setprop;
73 
74 	of_console_init();
75 
76 	of_init(promptr);
77 	loader_info.promptr = promptr;
78 	if (a1 && a2 && a2 != 0xdeadbeef) {
79 		loader_info.initrd_addr = a1;
80 		loader_info.initrd_size = a2;
81 	}
82 }
83 
84 void platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
85 		   unsigned long r6, unsigned long r7)
86 {
87 	/* Detect OF vs. ePAPR boot */
88 	if (r5)
89 		of_platform_init(r3, r4, (void *)r5);
90 	else
91 		epapr_platform_init(r3, r4, r5, r6, r7);
92 }
93 
94