1 /*
2 * Copyright (C) 1999, 2000, 2004, 2005 MIPS Technologies, Inc.
3 * All rights reserved.
4 * Authors: Carsten Langgaard <carstenl@mips.com>
5 * Maciej W. Rozycki <macro@mips.com>
6 * Portions copyright (C) 2009 Cisco Systems, Inc.
7 *
8 * This program is free software; you can distribute it and/or modify it
9 * under the terms of the GNU General Public License (Version 2) as
10 * published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
20 *
21 * PROM library initialisation code.
22 */
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/kernel.h>
26
27 #include <asm/bootinfo.h>
28 #include <linux/io.h>
29 #include <asm/cacheflush.h>
30 #include <asm/traps.h>
31
32 #include <asm/mips-boards/prom.h>
33 #include <asm/mips-boards/generic.h>
34 #include <asm/mach-powertv/asic.h>
35
36 static int *_prom_envp;
37 unsigned long _prom_memsize;
38
39 /*
40 * YAMON (32-bit PROM) pass arguments and environment as 32-bit pointer.
41 * This macro take care of sign extension, if running in 64-bit mode.
42 */
43 #define prom_envp(index) ((char *)(long)_prom_envp[(index)])
44
prom_getenv(char * envname)45 char *prom_getenv(char *envname)
46 {
47 char *result = NULL;
48
49 if (_prom_envp != NULL) {
50 /*
51 * Return a pointer to the given environment variable.
52 * In 64-bit mode: we're using 64-bit pointers, but all pointers
53 * in the PROM structures are only 32-bit, so we need some
54 * workarounds, if we are running in 64-bit mode.
55 */
56 int i, index = 0;
57
58 i = strlen(envname);
59
60 while (prom_envp(index)) {
61 if (strncmp(envname, prom_envp(index), i) == 0) {
62 result = prom_envp(index + 1);
63 break;
64 }
65 index += 2;
66 }
67 }
68
69 return result;
70 }
71
72 /* TODO: Verify on linux-mips mailing list that the following two */
73 /* functions are correct */
74 /* TODO: Copy NMI and EJTAG exception vectors to memory from the */
75 /* BootROM exception vectors. Flush their cache entries. test it. */
76
mips_nmi_setup(void)77 static void __init mips_nmi_setup(void)
78 {
79 void *base;
80 #if defined(CONFIG_CPU_MIPS32_R1)
81 base = cpu_has_veic ?
82 (void *)(CAC_BASE + 0xa80) :
83 (void *)(CAC_BASE + 0x380);
84 #elif defined(CONFIG_CPU_MIPS32_R2)
85 base = (void *)0xbfc00000;
86 #else
87 #error NMI exception handler address not defined
88 #endif
89 }
90
mips_ejtag_setup(void)91 static void __init mips_ejtag_setup(void)
92 {
93 void *base;
94
95 #if defined(CONFIG_CPU_MIPS32_R1)
96 base = cpu_has_veic ?
97 (void *)(CAC_BASE + 0xa00) :
98 (void *)(CAC_BASE + 0x300);
99 #elif defined(CONFIG_CPU_MIPS32_R2)
100 base = (void *)0xbfc00480;
101 #else
102 #error EJTAG exception handler address not defined
103 #endif
104 }
105
prom_init(void)106 void __init prom_init(void)
107 {
108 int prom_argc;
109 char *prom_argv;
110
111 prom_argc = fw_arg0;
112 prom_argv = (char *) fw_arg1;
113 _prom_envp = (int *) fw_arg2;
114 _prom_memsize = (unsigned long) fw_arg3;
115
116 board_nmi_handler_setup = mips_nmi_setup;
117 board_ejtag_handler_setup = mips_ejtag_setup;
118
119 if (prom_argc == 1) {
120 strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
121 strlcat(arcs_cmdline, prom_argv, COMMAND_LINE_SIZE);
122 }
123
124 configure_platform();
125 prom_meminit();
126
127 #ifndef CONFIG_BOOTLOADER_DRIVER
128 pr_info("\nBootloader driver isn't loaded...\n");
129 #endif
130 }
131